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ARTICLE 500 -- HAZARDOUS (CLASSIFIED) LOCATIONS, CLASSES I, II, AND III, DIVISIONS 1 AND 2

(Log #CP1401) 14- 2a - (500): Accept Note: The Technical Correlating Committee advises that Article Scope statements are the responsibility of the Technical Correlating Committee and the Technical Correlating Committee accepts the Panel Action. Further, it was the action of the Technical Correlating Committe this this Proposal be reconsidered by the Panel, with further consideration given to the comments expressed in the voting, specifically with respect to comments that the accepted Proposal does not accurately reflect what was agreed upon by the Panel. It is the understanding of the Technical Correlating Committee that this proposal is modified by Proposals 14-4a, 14-6, 14-20, 14-21, 14-33, 14-34, 14-38, 14-39, 14-42, 14-43, 1444, 14-45, 14-46, 14-47, 14-48, and 14-57a. This action will be considered by the Panel as a Public Comment. SUBMITTER: CMP 14 RECOMMENDATION: Revise Article 500 as shown: Entire 500 with recommended changes would appear as follows: ARTICLE 500 ­ Hazardous (Classified) Locations, Classes I, II, and III, Divisions 1 and 2 500-1. Scope -- Articles 500 through 504 Articles 500 through 504 cover the requirements for electrical and electronic equipment and wiring for all voltages in Class I, Divisions 1 and 2; Class II, Divisions 1 and 2; and Class III, Divisions 1 and 2 locations where fire or explosion hazards may exist due to flammable gases or vapors, flammable liquids, combustible dust, or ignitible fibers or flyings. FPN: For the requirements for electrical and electronic equipment and wiring for all voltages in Class I, Zone 0, Zone 1, and Zone 2 hazardous (classified) locations where fire or explosion hazards may exist due to flammable gases or vapors, or flammable liquids, refer to Article 505. 500-2 Definitions. For purposes of Articles 500 through 504 and Articles 506 through 516, the following definitions apply. Identified (a s applied to equipment). Recognizable as suitable for the specific purpose, function, use , environment, application, etc., where prescribed in a particular Code requirement. FPN: Suitability of equipment for a specific purpose, environment, or application may be determined by: 1. equipment listing or labeling; 2. evidence of equipment evaluation from a qualified testing laboratory or inspection agency concerned with product evaluation; or 3. other evidence acceptable to the authority having jurisdiction such as a manufacturer's self evaluation or an owner's engineering judgement. (See definitions of Labeled and Listed ) Unclassified Locations . Locations that have been evaluated by the classification process defined in Section 500-3 5(a) or Section 505-3 5 (a) and determined to be neither Class I, Division 1; Class I, Division 2; Class I, Zone 0; Class I, Zone 1; Class I, Zone 2; Class II, Division 1; Class II, Division 2; Class III, Division 1; Class III, Division 2; or any combination thereof. Nonhazardous Locations . Locations which are not required to have been evaluated by the process defined in 500-3 5 (a) or 505-35(a). Electrical and Electronic Equipment. Materials, fittings, devices, appliances, and the like that are part of, or in connection with an electrical installation, as well as any portable or transportable device having a battery or other electrical power source. (14-6) Dust-ignitionproof. Equipment enclosed in a manner that will exclude dusts and will not permit arcs, sparks, or heat otherwise generated or liberated inside of the enclosure to cause

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ignition of exterior accumulations or atmospheric suspensions of a specified dust on or in the vicinity of the enclosure. FPN: For further information on dust-ignitionproof enclosures, see Type 9 enclosure in Enclosures for Electrical Equipment, ANSI/NEMA 250-1991, and Explosionproof and DustIgnitionproof Electrical Equipment for Hazardous (Classified) Locations, ANSI/UL 1203-1994. Dusttight. Enclosures constructed so that dust will not enter under specified test conditions. FPN: See Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1 and 2 Hazardous (Classified) Locations, ANSI/ISA S12.12-1994, and Electrical Equipment for Use in Class I and II, Division 2 and Class III Hazardous (Classified) Locations, UL 1604-1994. Explosionproof Apparatus. Apparatus enclosed in a case that is capable of withstanding an explosion of a specified gas or vapor that may occur within it and of preventing the ignition of a specified gas or vapor surrounding the enclosure by sparks, flashes, or explosion of the gas or vapor within, and that operates at such an external temperature that a surrounding flammable atmosphere will not be ignited thereby. FPN: For further information, see Explosion-Proof and Dust-Ignition-Proof Electrical Equipment for Use in Hazardous (Classified) Locations, ANSI/UL 1203-1994. Purged and Pressurized. The process of supplying an enclosure with a protective gas, at a sufficient flow and positive pressure to reduce the concentration of any flammable gas or vapor initially present to an acceptable level. FPN: For further information, see Purged and Pressurized Enclosures for Electrical Equipment, ANSI/NFPA 4961998. Nonincendive Circuit. A circuit, other than field wiring, in which any arc or thermal effect produced under intended operating conditions of the equipment, is not capable, under specified test conditions, of igniting the flammable gas­, vapor­, or dust­air mixture. FPN: For further information see Nonincendive Electrical Equipment for Use in Class I and II, Division 2 and Class III, Divisions 1 and 2 Hazardous (Classified) Locations, ANSI/ISA-S12.12-1994. Nonincendive Field Wiring. Wiring that enters or leaves an equipment enclosure and, under normal operating conditions of the equipment, is not capable, due to arcing or thermal effects, of igniting the flammable gas­, vapor­, or dust­air mixture. Normal operation includes opening, shorting, or grounding the field wiring. Nonincendive Equipment. Equipment having electrical/electronic circuitry that is incapable, under normal operating conditions, of causing ignition of a specified flammable gas­, vapor­, or dust­air mixture due to arcing or thermal means. FPN: For further information, see Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1 and 2 Hazardous (Classified) Locations, ANSI/ISA-S12.12-1994. Nonincendive Component. A component having contacts for making or breaking an incendive circuit and the contacting mechanism shall be constructed so that the component is incapable of igniting the specified flammable gas­ or vapor­air mixture. The housing of a nonincendive component is not intended to exclude the flammable atmosphere or contain an explosion. FPN: For further information, see Electrical Equipment for Use in Class I and II, Division 2, and Class III Hazardous (Classified) Locations, UL 1604-1994. Oil Immersion. Electrical equipment immersed in a protective liquid in such a way that an explosive atmosphere that may be above the liquid or outside the enclosure cannot be ignited. FPN: For further information, see Industrial Control Equipment for Use in Hazardous (Classified) Locations, ANSI/UL 698-1995. Hermetically Sealed. Equipment sealed against the entrance of an external atmosphere where the seal is made by

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fusion, e.g., soldering, brazing, welding, or the fusion of glass to metal. FPN: For further information, see Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Division 1 and 2 Hazardous (Classified) Locations, ANSI/ISA S12.12-1994. 500-23. Other Articles Except as modified in Articles 500 through 504, all other applicable rules contained in this Code shall apply to electrical equipment and wiring installed in hazardous (classified) locations. 500-3 4 General (a) Documentation All areas designated as hazardous (classified) . locations shall be properly documented. This documentation shall be available to those authorized to design, install, inspect, maintain, or operate electrical equipment at the location. (b) Reference Standards. FPN No. 1: It is important that the authority having jurisdiction be familiar with recorded industrial experience as well as with the standards of the National Fire Protection Association, the American Petroleum Institute, and the Instrument Society of America that may be of use in the classification of various locations, the determination of adequate ventilation, and the protection against static electricity and lightning hazards. FPN No. 2: For further information on the classification of locations, see Flammable and Combustible Liquids Code, NFPA 30-1996; Standard for Drycleaning Plants, NFPA 32-1996; Standard for Spray Application Using Flammable or Combustible Materials, NFPA 33-1995; Standard for Dipping and Coating Processes Using Flammable or Combustible Liquids, NFPA 34-1995; Standard for the Manufacture of Organic Coatings, NFPA 35-1995; Standard for Solvent Extraction Plants, NFPA 361997; Standard on Fire Protection for Laboratories Using Chemicals, NFPA 45-1996; Standard for Gaseous Hydrogen Systems at Consumer Sites, NFPA 50A-1994; Standard for Liquefied Hydrogen Systems at Consumer Sites, NFPA 50B-1994; Liquefied Petroleum Gas Code, NFPA 58-1998; Standard for the Storage and Handling of Liquefied Petroleum Gases at Utility Gas Plants, NFPA 59-1998; Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 497-1997; Recommended Practice for the Classification of Combustible Dusts and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 499-1997; Standard for Fire Protection in Wastewater Treatment and Collection Facilities, NFPA 820-1995; Recommended Practice for Classification of Locations of Electrical Installations at Petroleum Facilities Classified as Class I, Division 1 and Division 2, ANSI/API RP500-1997; Area Classification In Hazardous (Classified) Dust Locations, ANSI/ISA-S12.10-1988. FPN No. 3: For further information on protection against static electricity and lightning hazards in hazardous (classified) locations, see Recommended Practice on Static Electricity, NFPA 77-1993; Standard for the Installation of Lightning Protection Systems, NFPA 7801997; and Protection Against Ignitions Arising Out of Static Lightning and Stray Currents, API RP 2003-1991. FPN No. 4: For further information on ventilation, see Flammable and Combustible Liquids Code, NFPA 301996; and Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Division 1 and Division 2, API RP 500-1997, Section 4.6. FPN No. 5: For further information on electrical systems for hazardous (classified) locations on offshore oil and gas producing platforms, see Recommended Practice for Design and Installation of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Division 1 and Division 2 Locations, ANSI/API RP 14F-1999.

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500-45. Classifications of Locations (a) Classifications of Locations. Locations shall be classified depending on the properties of the flammable vapors, liquids, or gases, or combustible dusts or fibers that may be present and the likelihood that a flammable or combustible concentration or quantity is present. Where pyrophoric materials are the only materials used or handled, these locations shall not be classified. Each room, section, or area shall be considered individually in determining its classification. FPN: Through the exercise of ingenuity in the layout of electrical installations for hazardous (classified) locations, it is frequently possible to locate much of the equipment in reduced level of classification or in an unclassified location less hazardous or in nonhazardous locations and, thus, to reduce the amount of special equipment required. Rooms and areas containing ammonia refrigeration systems that are equipped wit h adequate mechanical ventilation, may be classified as "unclassified" locations. FPN: For further information regrading classification and ventilaton of areas involving ammonia, see Safety Code for Mechanical Refrigeration, ANSI/ASHRAE 15-1994, and Safety Requirements for the Storage and Handling of Anhydrous Ammonia, ANSI/CGA G2.1-1989 (14-37) (b) Class I Locations Class I locations are those in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitible mixtures. Class I locations shall include those specified in (1) and (2). (1) Class I, Division 1. A Class I, Division 1 location is a location (a) In which ignitible concentrations of flammable gases or vapors can exist under normal operating conditions, or (b) In which ignitible concentrations of such gases or vapors may exist frequently because of repair or maintenance operations or because of leakage, or (c) In which breakdown or faulty operation of equipment or processes might release ignitible concentrations of flammable gases or vapors, and might also cause simultaneous failure of electrical equipment in such a way as to directly cause the electrical equipment to become a source of ignition. FPN No. 1: This classification usually includes the following locations: a. Where volatile flammable liquids or liquefied flammable gases are transferred from one container to another b. Interiors of spray booths and areas in the vicinity of spraying and painting operations where volatile flammable solvents are used c. Locations containing open tanks or vats of volatile flammable liquids d. Drying rooms or compartments for the evaporation of flammable solvents e. Locations containing fat and oil extraction equipment using volatile flammable solvents f. Portions of cleaning and dyeing plants where flammable liquids are used g. Gas generator rooms and other portions of gas manufacturing plants where flammable gas may escape h. Inadequately ventilated pump rooms for flammable gas or for volatile flammable liquids i. The interiors of refrigerators and freezers in which volatile flammable materials are stored in open, lightly stoppered, or easily ruptured containers j. All other locations where ignitible concentrations of flammable vapors or gases are likely to occur in the course of normal operations. FPN No. 2: In some Division 1 locations, ignitible concentrations of flammable gases or vapors may be present continuously or for long periods of time. Examples include the following: a. The inside of inadequately vented enclosures containing instruments normally venting

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flammable gases or vapors to the interior of the enclosure b. The inside of vented tanks containing volatile flammable liquids c. The area between the inner and outer roof sections of a floating roof tank containing volatile flammable fluids d. Inadequately ventilated areas within spraying or coating operations using volatile flammable fluids e. The interior of an exhaust duct that is used to vent ignitible concentrations of gases or vapors. Experience has demonstrated the prudence of avoiding the installation of instrumentation or other electric equipment in these particular areas altogether or where it cannot be avoided because it is essential to the process and other locations are not feasible [see Section 500-4 5(a), FPN], using electric equipment or instrumentation approved for the specific application or consisting of intrinsically safe systems as described in Article 504. (2) Class I, Division 2. A Class I, Division 2 location is a location (a) In which volatile flammable liquids or flammable gases are handled, processed, or used, but in which the liquids, vapors, or gases will normally be confined within closed containers or closed systems from which they can escape only in case of accidental rupture or breakdown of such containers or systems, or in case of abnormal operation of equipment, or (b) In which ignitible concentrations of gases or vapors are normally prevented by positive mechanical ventilation, and which might become hazardous through failure or abnormal operation of the ventilating equipment, or (c) That is adjacent to a Class I, Division 1 location, and to which ignitible concentrations of gases or vapors might occasionally be communicated unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air, and effective safeguards against ventilation failure are provided. FPN No. 1: This classification usually includes locations where volatile flammable liquids or flammable gases or vapors are used but that, in the judgment of the authority having jurisdiction, would become hazardous only in case of an accident or of some unusual operating condition. The quantity of flammable material that might escape in case of accident, the adequacy of ventilating equipment, the total area involved, and the record of the industry or business with respect to explosions or fires are all factors that merit consideration in determining the classification and extent of each location. FPN No. 2: Piping without valves, checks, meters, and similar devices would not ordinarily introduce a hazardous condition even though used for flammable liquids or gases. Depending on factors such as the quantity and size of the containers and ventilation, locations used for the storage of flammable liquids or liquefied or compressed gases in sealed containers may either be considered hazardous (classified) or nonhazardous locations. See Flammable and Combustible Liquids Code, NFPA 30-1996, and Liquefied Petroleum Gas Code, NFPA 58-1998. (c) Class II Locations Class II locations are those that are hazardous because of the presence of combustible dust. Class II locations shall include those specified in (a) and (b). (1) Class II, Division 1. A Class II, Division 1 location is a location (a) In which combustible dust is in the air under normal operating conditions in quantities sufficient to produce explosive or ignitible mixtures, or (b) Where mechanical failure or abnormal operation of machinery or equipment might cause such explosive or ignitible mixtures to be produced, and might also provide a source of ignition through simultaneous failure of electric equipment, operation of protection devices, or from other causes, or (c) In which combustible dusts of an electrically conductive nature may be present in hazardous quantities. FPN: Combustible dusts that are electrically nonconductive include dusts produced in the handling and processing of grain and grain products, pulverized sugar and cocoa, dried egg and milk powders, pulverized

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spices, starch and pastes, potato and wood-flour, oil meal from beans and seed, dried hay, and other organic materials that may produce combustible dusts when processed or handled. Only Group E dusts are considered to be electrically conductive for classification purposes. Dusts containing magnesium or aluminum are particularly hazardous, and the use of extreme precaution will be necessary to avoid ignition and explosion.

(2) Class II, Division 2 . A Class II, Division 2 location is a location (a) Where combustible dust is not normally in the air in quantities sufficient to produce explosive or ignitible mixtures, and dust accumulations are normally insufficient to interfere with the normal operation of electrical equipment or other apparatus, but combustible dust may be in suspension in the air as a result of infrequent malfunctioning of handling or processing equipment and (b) Where combustible dust accumulations on, in, or in the vicinity of the electrical equipment may be sufficient to interfere with the safe dissipation of heat from electrical equipment or may be ignitible by abnormal operation or failure of electrical equipment. FPN No. 1: The quantity of combustible dust that may be present and the adequacy of dust removal systems are factors that merit consideration in determining the classification and may result in an nonhazardous area. FPN No. 2: Where products such as seed are handled in a manner that produces low quantities of dust, the amount of dust deposited may not warrant classification. (d) Class III Locations Class III locations are those that are hazardous because of the presence of easily ignitible fibers or flyings, but in which such fibers or flyings are not likely to be in suspension in the air in quantities sufficient to produce ignitible mixtures. Class III locations shall include those specified in (a) and (b). (1) Class III, Division 1 . A Class III, Division 1 location is a location in which easily ignitible fibers or materials producing combustible flyings are handled, manufactured, or used. FPN No. 1: Such locations usually include some parts of rayon, cotton, and other textile mills; combustible fiber manufacturing and processing plants; cotton gins and cotton-seed mills; flax-processing plants; clothing manufacturing plants; woodworking plants; and establishments and industries involving similar hazardous processes or conditions. FPN No. 2: Easily ignitible fibers and flyings include rayon, cotton (including cotton linters and cotton waste), sisal or henequen, istle, jute, hemp, tow, cocoa fiber, oakum, baled waste kapok, Spanish moss, excelsior, and other materials of similar nature. (2) Class III, Division 2. A Class III, Division 2 location is a location in which easily ignitible fibers are stored or handled other than in the process of manufacture. 500-5 6 Material Groups For purposes of testing, approval, and area classification, various air mixtures (not oxygen-enriched) shall be grouped in accordance with Sections 500-56(a) and 500-5 6(b). Exception: Equipment approved for a specific gas, vapor, or dust. FPN: This grouping is based on the characteristics of the materials. Facilities are available for testing and identifying equipment for use in the various atmospheric groups. (a) Class I Group Classifications . Class I groups shall be as follows. (1) Group A. Acetylene. (2) Group B. Flammable gas, flammable liquid­produced vapor, or combustible liquid­produced vapor mixed with air that may burn or explode, having either a maximum experimental safe gap (MESG) value less than or equal to 0.45 mm or a minimum igniting current ratio (MIC ratio) less than or equal to 0.40. FPN: A typical Class I, Group B material is hydrogen.

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Exception No. 1: Group D equipment shall be permitted to be used for for Coal and Coke, ASTM D3175-89, for coal and coke dusts) or atmospheres containing butadiene provided all conduit runs into that have been sensitized by other materials so that they present an explosionproof equipment are provided with explosionproof seals installed explosion hazard. Coal, carbon black, charcoal, and coke dusts are within 18 in. (457 mm) of the enclosure. examples of carbonaceous dusts. Exception No. 2: Group C equipment shall be permitted to be used for atmospheres containing allyl glycidyl ether, n-butyl glycidyl ether, (3) Group G. Atmospheres containing combustible dusts not ethylene oxide, propylene oxide, and acrolein provided all conduit runs included in Group E or F, including flour, grain, wood, plastic, into explosionproof equipment are provided with explosionproof seals and chemicals. installed within 18 in. (457 mm) of the enclosure. FPN No. 1: For additional information on group classification of Class II materials, see Recommended (3) Group C. Flammable gas, flammable liquid­produced vapor, Practice for the Classification of Combustible Dusts and or combustible liquid­produced vapor mixed with air that may of Hazardous (Classified) Locations for Electrical burn or explode, having either a maximum experimental safe gap Installations in Chemical Process Areas, NFPA 499-1997. (MESG) value greater than 0.45 mm and less than or equal to 0.75 mm, or a minimum igniting current ratio (MIC ratio) greater than FPN No. 2: The explosion characteristics of air mixtures 0.40 and less than or equal to 0.80. of dust vary with the materials involved. For Class II FPN: A typical Class I, Group C material is ethylene. locations, Groups E, F, and G, the classification involves the tightness of the joints of assembly and shaft openings (4) Group D. Flammable gas, flammable liquid­produced vapor, to prevent the entrance of dust in the dust-ignitionproof or combustible liquid­produced vapor mixed with air that may enclosure, the blanketing effect of layers of dust on the burn or explode, having either a maximum experimental safe gap equipment that may cause overheating, and the ignition (MESG) value greater than 0.75 mm or a minimum igniting current temperature of the dust. It is necessary, therefore, that ratio (MIC ratio) greater than 0.80. equipment be approved not only for the class, but also FPN No. 1: A typical Class I, Group D material is for the specific group of dust that will be present. propane. FPN No. 3: Certain dusts may require additional FPN No. 2: For classification of areas involving ammonia precautions due to chemical phenomena that can result atmosphere, see Safety Code for Mechanical in the generation of ignitible gases. See National Refrigeration, ANSI/ASHRAE 15-1994, and Safety Electrical Safety Code, ANSI C2-1997, Section 127A, Coal Requirements for the Storage and Handling of Handling Areas. Anhydrous Ammonia, ANSI/CGA G2.1-1989. Exception: For atmospheres containing ammonia, the authority having 500 -6 7 Protection Techniques jurisdiction for enforcement of this Code shall be permitted to reclassify The following shall be acceptable protection techniques for the location to reduced level of classification or to an unclassified a less electrical and electronic equipment in hazardous (classified) hazardous location or a nonhazardous location.(14-37) locations. FPN No. 1: For additional information on the properties and group classification of Class I materials, see (a) Explosionproof Apparatus. This protection technique shall be Recommended Practice for the Classification of permitted for equipment in Class I, Division 1 or 2 locations. Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in (b) Dust Ignitionproof. This protection technique shall be Chemical Process Areas, NFPA 497-1997, and Guide to permitted for equipment in Class II, Division 1 or 2 locations. Fire Hazard Properties of Flammable Liquids, Gases, and Volatile Solids, NFPA 325-1994. (c) Dusttight. This protection technique shall be permitted for The following FPN 's apply to section (a): equipment in Class II, Division 2 or Class III locations. FPN No. 1: The explosion characteristics of air mixtures of gases or vapors vary with the specific material involved. For Class I (d) Purged and Pressurized. This protection technique shall be locations, Groups A, B, C, and D, the classification involves permitted for equipment in any hazardous (classified) location for determinations of maximum explosion pressure and maximum which it is approved. safe clearance between parts of a clamped joint in an enclosure. It is necessary, therefore, that equipment be approved not only for (e) Intrinsic Safety. This protection technique shall be permitted class but also for the specific group of the gas or vapor that will be for equipment in Class I, Division 1 or 2, or Class II, Division 1 or present. 2, or Class III, Division 1 or 2 locations. The provisions of Articles FPN No. 2: Certain chemical atmospheres may have characteristics 501 through 503 and 510 through 516 shall not be considered that require safeguards beyond those required for any of the above applicable to such installations, except as required by Article 504, groups. Carbon disulfide is one of these chemicals because of its and installation of intrinsically safe apparatus and wiring shall be in low ignition temperature [100ºC (212ºF)] and the small joint accordance with the requirements of Article 504. clearance permitted to arrest its flame. FPN No. 3: For classification of areas involving ammonia (f) Nonincendive Circuit. This protection technique shall be atmosphere, see Safety Code for Mechanical Refrigeration, permitted for equipment in Class I, Division 2, Class II, Division 2, ANSI/ASHRAE 15-1994, and Safety Requirements for the Storage Class III, Division 2 locations. and Handling of Anhydrous Ammonia, ANSI/CGA G2.1-1989. (g) Nonincendive Equipment. This protection technique shall be (b) Class II Group Classifications. Class II groups shall be as permitted for equipment in Class I, Division 2, Class II, Division 2, follows. Class III, and Division 2 locations. (1) Group E. Atmospheres containing combustible metal dusts, including aluminum, magnesium, and their commercial alloys, or other combustible dusts whose particle size, abrasiveness, and conductivity present similar hazards in the use of electrical equipment. FPN: Certain metal dusts may have characteristics that require safeguards beyond those required for atmospheres containing the dusts of aluminum, magnesium, and their commercial alloys. For example, zirconium, thorium, and uranium dusts have extremely low ignition temperatures [as low as 20ºC (68ºF)] and minimum ignition energies lower than any material classified in any of the Class I or Class II Groups. (2) Group F. Atmospheres containing combustible carbonaceous dusts that have more than 8 percent total entrapped volatiles (see Standard Test Method for Volatile Material in the Analysis Sample (h) Nonincendive Component This protection technique shall be . permitted for equipment in Class I, Division 2, Class II, Division 2, Class III, Division 2 locations. (i) Nonincendive Component. This protection technique shall be permitted for current-interrupting contacts in those Class I, Division 2 locations for which the component is approved. (j) Oil Immersion. This protection technique shall be permitted for current-interrupting contacts in Class I, Division 2 locations as described in Section 501-67(b)(1)(b). (k) Hermetically Sealed. This protection technique shall be permitted for equipment in Class I and II, Division 2, and Class III, Division 1 and 2 locations.

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(l) Other Protection Techniques. Other protection techniques used in equipment listed for use in hazardous (classified) locations. 500 -7 8 Equipment Articles 500 through 504 require equipment construction and installation that will ensure safe performance under conditions of proper use and maintenance. FPN No. 1: It is important that inspection authorities and users exercise more than ordinary care with regard to installation and maintenance. FPN No. 2: Low ambient conditions require special consideration. Explosionproof or dust-ignitionproof equipment may not be suitable for use at temperatures lower than -25ºC (-13ºF) unless they are identified for low-temperature service. However, at low ambient temperatures, flammable concentrations of vapors may not exist in a location classified Class I, Division 1 at normal ambient temperature.

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Division 1 and 2 locations. Equipment marked "Division 2" or "Div. 2" is suitable for Division 2 locations only.

The temperature class range, if provided, shall be indicated using the temperature class (T Codes) in identification numbers, as shown in Table 500-7 8(b). The temperature class (T Code)Identification numbers marked on equipment nameplates shall be in accordance with Table 50087(b). Equipment that is approved for Class I and Class II shall be marked with the maximum safe operating temperature, as determined by simultaneous exposure to the combinations of Class I and Class II conditions. FPN: Since there is no consistent relationship between explosion properties and ignition temperature, the two are independent requirements. Table 500-8( b ). Classification of Maximum Surface Temperature Identification Numbers

(a) Approval for Class and Properties. (1) Equipment shall be approved not only for the class of location Maximum Identification Temperature but also for the explosive, combustible, or ignitible properties of Temperature NumberClass (T Code) the specific gas, vapor, dust, fiber, or flyings that will be present. In ºC ºF addition, Class I equipment shall not have any exposed surface that 450 842 T1 operates at a temperature in excess of the ignition temperature of 300 572 T2 the specific gas or vapor. Class II equipment shall not have an 280 536 T2A external temperature higher than that specified in Section 500260 500 T2B 78(2). Class III equipment shall not exceed the maximum surface 230 446 T2C temperatures specified in Section 503-1. 215 419 T2D (2) Equipment that has been approved for a Division 1 location shall be permitted in a Division 2 location of the same class and 200 392 T3 group. 180 356 T3A (3) Where specifically permitted in Articles 501 through 503, 165 329 T3B general-purpose equipment or equipment in general-purpose 160 320 T3C enclosures shall be permitted to be installed in Division 2 locations 135 275 T4 if the equipment does not constitute a source of ignition under 120 248 T4A normal operating conditions. 100 212 T5 (4) Equipment, regardless of the classification of the location in 85 185 T6 which it is installed, that depends on a single compression seal, diaphragm, or tube to prevent flammable or combustible fluids from entering the equipment, shall be approved for a Class I, (c) Temperature Division 2 location. (1) Class I Temperature. The temperature marking specified in (b) Exception: Equipment installed in a Class I, Division 1 location shall be shall not exceed the ignition temperature of the specific gas or suitable for the Division 1 location. vapor to be encountered. FPN: See Section 501-5(f)(3) for additional FPN: For information regarding ignition temperatures of requirements. gases and vapors, see Recommended Practice for the Classification of flammable gases, etc. and of Hazardous (5) Unless otherwise specified, normal operating conditions for (Classified) Locations for Electrical Installations in motors shall be assumed to be rated full-load steady conditions. Chemical Process Areas, NFPA 497-1997. (6) Where flammable gases or combustible dusts are or may be present at the same time, the simultaneous presence of both shall (2) Class II Temperature. The temperature marking specified in be considered when determining the safe operating temperature of (b) shall be less than the ignition temperature of the specific dust the electrical equipment. to be encountered. For organic dusts that may dehydrate or FPN: The characteristics of various atmospheric mixtures carbonize, the temperature marking shall not exceed the lower of of gases, vapors, and dusts depend on the specific either the ignition temperature or 165ºC (329ºF). material involved. FPN: See Recommended Practice for the Classification of Combustible Dusts and of Hazardous (Classified) (b) Marking. Equipment shall be marked to show the class, group, Locations for Electrical Installations in Chemical Process and operating temperature or temperature class range referenced Areas, NFPA 499-1997, for minimum ignition temperatures of specific dusts. to a 40ºC ambient. The ignition temperature for which equipment was approved prior Exception No. 1: Equipment of the non-heat-producing type, such as to this requirement shall be assumed to be as shown in Table 500junction boxes, conduit, and fittings, and equipment of the heat5(c) (2). producing type having a maximum temperature not more than 100ºC Table 500-5(c) (2). (212ºF) shall not be required to have a marked operating temperature or temperature range class . Equipment (Such as Motors or Power Exception No. 2: Fixed lighting fixtures marked for use in Class I, Transformers) that May Be Overloaded Division 2 or Class II, Division 2 locations only shall not be required to Equipment that Is be marked to indicate the group. Not Subject to Normal Abnormal Exception No. 3: Fixed general-purpose equipment in Class I locations, Overloading Operation other than fixed lighting fixtures, that is acceptable for use in Class I, Operation Division 2 locations shall not be required to be marked with the class, Class II Group ºC ºF ºC ºF group, division, or operating temperature. ºC ºF Exception No. 4: Fixed dusttight equipment other than fixed lighting E 200 392 200 392 200 fixtures that are acceptable for use in Class II, Division 2 and Class III 392 locations shall not be required to be marked with the class, group, F 200 392 150 302 200 division, or operating temperature. 392 Exception No. 5: Electric equipment suitable for ambient temperatures G 165 329 120 248 165 exceeding 40ºC (104ºF) shall be marked with both the maximum ambient 329 temperature and the operating temperature or temperature at class range that ambient temperature. (d) Threading FPN: Equipment not marked to indicate a division, or marked "Division 1" or "Div. 1," is suitable for both

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All threaded conduit referred to herein shall be threaded with an National (American) Standard Pipe Taper (NPT ) standard conduit cutting die that provides _-in. taper per foot. Such conduit shall be made wrenchtight to prevent sparking when fault current flows through the conduit system, and to ensure the explosionproof or flameproof integrity of the conduit system where applicable. Equipment provided with threaded entries for field wiring connections shall be installed in accordance with (1) or (2). (1) Equipment Provided with Threaded Entries for NPT Threaded Conduit or Fittings. For equipment provided with threaded entries for NPT threaded conduit or fittings, listed conduit, conduit fittings, or cable fittings shall be used. FPN: Threading specifications for NPT threads are located in Pipe Threads, General Purpose (Inch), ANSI/ASME B1.20.1-1983. (2) Equipment Provided with Threaded Entries for Metric Threaded Conduit or Fittings. For equipment with metric threaded entries, such entries shall be identified as being metric, or listed adapters to permit connection to conduit or NPT-threaded fittings shall be provided with the equipment. Adapters shall be used for connection to conduit or NPT-threaded fittings. Listed cable fittings that have metric threads shall be permitted to be used. FPN: Threading specifications for metric threaded entries are located in Metric Screw Threads, ISO 965/1:1980, and Metric Screw Threads, ISO 965/3:1980. (e) Fiber Optic Cable Assembly. Where a fiber optic cable assembly contains conductors that are capable of carrying current, the fiber optic cable assembly shall be installed in accordance with the requirements of Articles 500, 501, 502, or 503, as applicable. 500-9. Specific Occupancies Articles 510 through 517 cover garages, aircraft hangars, gasoline dispensing and service stations, bulk storage plants, spray application, dipping and coating processes, and health care facilities. SUBSTANTIATION: This complete revision of Article 500 editorially revises the text to make it more easily understood and also incorporates numerous technical and editorial improvements made via other proposals. PANEL ACTION: Accept. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban COMMENT ON AFFIRMATIVE: BRIESCH: While the Panel Action to accept the rewrite of Article 500 is supported, the NFPA-Circulated Panel Proposal does not include all of the changes agreed to at the meeting. The e-mail sent by Dave Wechsler subsequent to the meeting is more complete in reflecting the Panel Actions from the meeting. COOK: I agree with Proposal 14-2a and the substantiation, however, it does not incorporate all of the changes made via other proposals. An updated version that was emailed from Dave Wechsler on 1-26-2000 seems to be more complete with respect to including Panel Actions from the meeting in Hilton Head. I agree with the proposals submitted to change the term "nonhazardous" to "unclassified". During the panel discussion, the term "nonhazardous" was defined and also used in certain applications. After considering discussion and reviewing written ballots, I believe that some evaluation is done on every installation and a determination is made to use ordinary electrical equipment, or continue more extensive evaluation and possibly use some special equipment. I believe that defining and using two terms would complicate the issue. I believe we should define and use the term "unclassified" and drop "nonhazardous." ENGLER: Not all of the changes made it into the draft circulated with this ballot, vote is to affirm the text with all of the necessary changes made to it. GOODMAN: Part 1, Rewritten Article is inconsistent with other Panel Actions and has missing or incorrect information. Rewritten Article requires additional backchecking. Examples: Panel Action to Proposal 14-20 to "Purged and Pressurized" (new Section 500-7(d)) was to use "Identified" but is shown in draft as "Approved"; redundant paragraphs numbered 500-7(h) and 500-7(i); added text of Proposal 14-30 and 14-31 is missing from draft, and new text or modified text is not identified accurately in the margin.

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Part 2, this comment recommends change to a specific part of the rewritten Article. In the new Section 500-2 Definitions, the term "Nonhazardous" has been included. This comment recommends the removal of this term, definition, and use for the following reasons: 1. This term was added as part of the Panel Chairman assigned Task Group responsible for reorganizing the information in Article 500. This term and definition are new material and beyond the scope of the Panel Chair's direction. 2. The added term and definition was not part of any Proposal made to the Panel and has no substantiation for its inclusion. 3. Several Proposals (14-8, 14-40, 14-315, and 14-316) specifically requested that the term "nonhazardous" currently used in the Article be deleted and substituted with the term "unclassified". 4. This term adds an additional area classification location that does not currently exist in related standards and practices (API 500 and 505 for example) or in most company documentation systems. 5. The term is misleading. The implication of "nonhazardous" is that there are no hazards. There are hazards other than electrical area classification such as caustics, acids, radiation, etc. Using the term "unclassified" is becoming widely accepted and recognized as specific to electrical area classification. "Nonhazardous" is much too broad. 6. The term is not needed. An area is either "Classified", requiring specifically identified or approved equipment suitable for the location or "Unclassified", not requiring equipment so identified or approved. The term will only add confusion and potential misapplication. 7. By its definition, "Nonhazardous Locations. Locations which are not required to have been evaluated". Whoever makes the determination that the location is not required to be evaluated has just evaluated the location. It is also not at all clear how or who would make that determination. For the above reasons, the term "Nonhazardous", its definition and use should be removed from Article 500 and (505). JAGUNICH: The definitions of "nonincendive field wiring apparatus" and "associated nonincendive field wiring apparatus" were established by CMP14 and do not appear in panel proposal 14-2a as sent in the ballot. These definition should included. LAWRENCE: Due to the large number of public proposals received and acted upon, and also due to time constraints, the panel was not able to compile and correlate all aspects of the rewrites of the affected article. Please see David Wechsler's ballot OMEARA: Please see the comments on the ballot for David Wechsler. WECHSLER: While attempts were made to provide NFPA staff with corrected revisions of this text before the end of the CMP 14 panel meeting, a detailed review of this balloted draft version has indicated that this does not reflect the correct committee actions and is not correct. We attribute the problems with this draft to the following: a) the use of several earlier drafts that were consistently being revised to keep pace with changes made due to committee actions on public proposals, b) the limited time available to proof and develop this work, c) the extremely large number of public proposals, d) the complex nature of the interaction of affected texts within Articles 500, 501, 502, and 505, and the desire of the panel to maintain consistency, and e) human errors in transcribing this information. The following text provides a correct revision of this complete work effort for Article 500. This text should be the panel document of record and not that provided with the panel ballot. Entire 500 with recommended changes would appear as follows: ARTICLE 500 ­ Hazardous (Classified) Locations, Classes I, II, and III, Divisions 1 and 2 500-1. Scope -- Articles 500 through 504 Articles 500 through 504 cover the requirements for electrical and electronic equipment and wiring for all voltages in Class I, Divisions 1 and 2; Class II, Divisions 1 and 2; and Class III, Divisions 1 and 2 locations where fire or explosion hazards may exist due to flammable gases or vapors, flammable liquids, combustible dust, or ignitible fibers or flyings. FPN: For the requirements for electrical and electronic equipment and wiring for all voltages in Class I, Zone 0, Zone 1, and Zone 2 hazardous (classified) locations where fire or explosion hazards may exist due to flammable gases or vapors, or flammable liquids, refer to Article 505.

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500-2 Definitions. For purposes of Articles 500 through 504 and Articles 506 through 516, the following definitions apply. Identified (as applied to equipment). Recognizable as suitable for the specific purpose, function, use, environment, application, etc., where prescribed in a particular Code requirement. FPN: Suitability of equipment for a specific purpose, environment, or application may be determined by: 1.2. equipment listing or labeling; 2. evidence of equipment evaluation from a qualified test ing laboratory or inspection agency concerned with product evaluation; or 3. other evidence acceptable to the authority having jurisdiction such as a manufacturer's self evaluation or an owner's engineering judgement. (See definitions of Labeled and Listed) Unclassified Locations . Locations that have been evaluated by the classification process defined in Section 500-3 5(a) or Section 505-3 5 (a) and determined to be neither Class I, Division 1; Class I, Division 2; Class I, Zone 0; Class I, Zone 1; Class I, Zone 2; Class II, Division 1; Class II, Division 2; Class III, Division 1; Class III, Division 2; or any combination thereof. Nonhazardous Locations. Locations which are not required to have been evaluated by the process defined in 500-3 5 (a) or 505-35(a). Electrical and Electronic Equipment. Materials, fittings, devices, appliances, and the like that are part of, or in connection with an electrical installation, as well as any portable or transportable device having a battery or other electrical power source. (14-6) Dust-ignitionproof. Equipment enclosed in a manner that will exclude dusts and will not permit arcs, sparks, or heat otherwise generated or liberated inside of the enclosure to cause ignition of exterior accumulations or atmospheric suspensions of a specified dust on or in the vicinity of the enclosure. FPN: For further information on dust-ignitionproof enclosures, see Type 9 enclosure in Enclosures for Electrical Equipment, ANSI/NEMA 250-1991, and Explosionproof and DustIgnitionproof Electrical Equipment for Hazardous (Classified) Locations, ANSI/UL 1203-1994. Dusttight. Enclosures constructed so that dust will not enter under specified test conditions. FPN: See Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1 and 2 Hazardous (Classified) Locations, ANSI/ISA S12.12-1994, and Electrical Equipment for Use in Class I and II, Division 2 and Class III Hazardous (Classified) Locations, UL 1604-1994. Explosionproof Apparatus. Apparatus enclosed in a case that is capable of withstanding an explosion of a specified gas or vapor that may occur within it and of preventing the ignition of a specified gas or vapor surrounding the enclosure by sparks, flashes, or explosion of the gas or vapor within, and that operates at such an external temperature that a surrounding flammable atmosphere will not be ignited thereby. FPN: For further information, see Explosion-Proof and Dust-Ignition-Proof Electrical Equipment for Use in Hazardous (Classified) Locations, ANSI/UL 1203-1994. Purged and Pressurized. The process of supplying an enclosure with a protective gas, at a sufficient flow and positive pressure to reduce the concentration of any flammable gas or vapor initially present to an acceptable level. FPN: For further information, see Purged and Pressurized Enclosures for Electrical Equipment, ANSI/NFPA 4961998. Nonincendive Circuit. A circuit, other than field wiring, in which any arc or thermal effect produced under intended operating conditions of the equipment, is not capable, under specified test conditions, of igniting the flammable gas­, vapor­, or dust­air mixture. FPN: For further information see Nonincendive Electrical Equipment for Use in Class I and II, Division 2 and Class

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III, Divisions 1 and 2 Hazardous (Classified) Locations, ANSI/ISA-S12.12-1994. Nonincendive Field Wiring. Wiring that enters or leaves an equipment enclosure and, under normal operating conditions of the equipment, is not capable, due to arcing or thermal effects, of igniting the flammable gas­, vapor­, or dust­air mixture. Normal operation includes opening, shorting, or grounding the field wiring. Nonincendive Equipment. Equipment having electrical/electronic circuitry that is incapable, under normal operating conditions, of causing ignition of a specified flammable gas­, vapor­, or dust­air mixture due to arcing or thermal means. FPN: For further information, see Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1 and 2 Hazardous (Classified) Locations, ANSI/ISA-S12.12-1994. Nonincendive Component. A component having contacts for making or breaking an incendive circuit and the contacting mechanism shall be constructed so that the component is incapable of igniting the specified flammable gas­ or vapor­air mixture. The housing of a nonincendive component is not intended to exclude the flammable atmosphere or contain an explosion. FPN: For further information, see Electrical Equipment for Use in Class I and II, Division 2, and Class III Hazardous (Classified) Locations, UL 1604-1994. Oil Immersion. Electrical equipment immersed in a protective liquid in such a way that an explosive atmosphere that may be above the liquid or outside the enclosure cannot be ignited. FPN: For further information, see Industrial Control Equipment for Use in Hazardous (Classified) Locations, ANSI/UL 698-1995. Hermetically Sealed. Equipment sealed against the entrance of an external atmosphere where the seal is made by fusion, e.g., soldering, brazing, welding, or the fusion of glass to metal. FPN: For further information, see Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Division 1 and 2 Hazardous (Classified) Locations, ANSI/ISA S12.12-1994. 500-23. Other Articles Except as modified in Articles 500 through 504, all other applicable rules contained in this Code shall apply to electrical equipment and wiring installed in hazardous (classified) locations. 500-3 4 General (a) Documentation All areas designated as hazardous (classified) . locations shall be properly documented. This documentation shall be available to those authorized to design, install, inspect, maintain, or operate electrical equipment at the location. (b) Reference Standards. FPN No. 1: It is important that the authority having jurisdiction be familiar with recorded industrial experience as well as with the standards of the National Fire Protection Association, the American Petroleum Institute, and the Instrument Society of America that may be of use in the classification of various locations, the determination of adequate ventilation, and the protection against static electricity and lightning hazards. FPN No. 2: For further information on the classification of locations, see Flammable and Combustible Liquids Code, NFPA 30-1996; Standard for Drycleaning Plants, NFPA 32-1996; Standard for Spray Application Using Flammable or Combustible Materials, NFPA 33-1995; Standard for Dipping and Coating Processes Using Flammable or Combustible Liquids, NFPA 34-1995; Standard for the Manufacture of Organic Coatings, NFPA 35-1995; Standard for Solvent Extraction Plants, NFPA 361997; Standard on Fire Protection for Laboratories Using Chemicals, NFPA 45-1996; Standard for Gaseous Hydrogen Systems at Consumer Sites, NFPA 50A-1994; Standard for Liquefied Hydrogen Systems at Consumer Sites, NFPA 50B-1994; Liquefied Petroleum Gas Code,

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NFPA 58-1998; Standard for the Storage and Handling of Liquefied Petroleum Gases at Utility Gas Plants, NFPA 59-1998; Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 497-1997; Recommended Practice for the Classification of Combustible Dusts and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 499-1997; Standard for Fire Protection in Wastewater Treatment and Collection Facilities, NFPA 820-1995; Recommended Practice for Classification of Locations of Electrical Installations at Petroleum Facilities Classified as Class I, Division 1 and Division 2, ANSI/API RP500-1997; Area Classification In Hazardous (Classified) Dust Locations, ANSI/ISA-S12.10-1988. FPN No. 3: For further information on protection against static electricity and lightning hazards in hazardous (classified) locations, see Recommended Practice on Static Electricity, NFPA 77-1993; Standard for the Installation of Lightning Protection Systems, NFPA 7801997; and Protection Against Ignitions Arising Out of Static Lightning and Stray Currents, API RP 2003-1991. FPN No. 4: For further information on ventilation, see Flammable and Combustible Liquids Code, NFPA 301996; and Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Division 1 and Division 2, API RP 500-1997, Section 4.6. FPN No. 5: For further information on electrical systems for hazardous (classified) locations on offshore oil and gas producing platforms, see Recommended Practice for Design and Installation of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Division 1 and Division 2 Locations, ANSI/API RP 14F-1999. 500-45. Classifications of Locations (a) Classifications of Locations. Locations shall be classified depending on the properties of the flammable vapors, liquids, or gases, or combustible dusts or fibers that may be present and the likelihood that a flammable or combustible concentration or quantity is present. Where pyrophoric materials are the only materials used or handled, these locations shall not be classified. Each room, section, or area shall be considered individually in determining its classification. FPN: Through the exercise of ingenuity in the layout of electrical installations for hazardous (classified) locations, it is frequently possible to locate much of the equipment in reduced level of classification or in an unclassified location less hazardous or in nonhazardous locations and, thus, to reduce the amount of special equipment required. Rooms and areas containing ammonia refrigeration systems that are equipped with adequate mechanical ventilation, may be classified as "unclassified" locations. FPN: For further information regrading classification and ventilaton of areas involving ammonia, see Safety Code for Mechanical Refrigeration, ANSI/ASHRAE 15-1994, and Safety Requirements for the Storage and Handling of Anhydrous Ammonia, ANSI/CGA G2.1-1989 (14-37) (b) Class I Locations Class I locations are those in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitible mixtures. Class I locations shall include those specified in (1) and (2). (1) Class I, Division 1. A Class I, Division 1 location is a location (a) In which ignitible concentrations of flammable gases or vapors can exist under normal operating conditions, or (b) In which ignitible concentrations of such gases or vapors may exist frequently because of repair or maintenance operations or because of leakage, or (c) In which breakdown or faulty operation of equipment or processes might release ignitible concentrations of flammable gases

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or vapors, and might also cause simultaneous failure of electrical equipment in such a way as to directly cause the electrical equipment to become a source of ignition. FPN No. 1: This classification usually includes the following locations: a. Where volatile flammable liquids or liquefied flammable gases are transferred from one container to another b. Interiors of spray booths and areas in the vicinity of spraying and painting operations where volatile flammable solvents are used c. Locations containing open tanks or vats of volatile flammable liquids d. Drying rooms or compartments for the evaporation of flammable solvents e. Locations containing fat and oil extraction equipment using volatile flammable solvents f. Portions of cleaning and dyeing plants where flammable liquids are used g. Gas generator rooms and other portions of gas manufacturing plants where flammable gas may escape h. Inadequately ventilated pump rooms for flammable gas or for volatile flammable liquids i. The interiors of refrigerators and freezers in which volatile flammable materials are stored in open, lightly stoppered, or easily ruptured containers j. All other locations where ignitible concentrations of flammable vapors or gases are likely to occur in the course of normal operations. FPN No. 2: In some Division 1 locations, ignitible concentrations of flammable gases or vapors may be present continuously or for long periods of time. Examples include the following: a. The inside of inadequately vented enclosures containing instruments normally venting flammable gases or vapors to the interior of the enclosure b. The inside of vented tanks containing volatile flammable liquids c. The area between the inner and outer roof sections of a floating roof tank containing volatile flammable fluids d. Inadequately ventilated areas within spraying or coating operations using volatile flammable fluids e. The interior of an exhaust duct that is used to vent ignitible concentrations of gases or vapors. Experience has demonstrated the prudence of avoiding the installation of instrumentation or other electric equipment in these particular areas altogether or where it cannot be avoided because it is essential to the process and other locations are not feasible [see Section 500-4 5(a), FPN], using electric equipment or instrumentation approved for the specific application or consisting of intrinsically safe systems as described in Article 504. (2) Class I, Division 2. A Class I, Division 2 location is a location (a) In which volatile flammable liquids or flammable gases are handled, processed, or used, but in which the liquids, vapors, or gases will normally be confined within closed containers or closed systems from which they can escape only in case of accidental rupture or breakdown of such containers or systems, or in case of abnormal operation of equipment, or (b) In which ignitible concentrations of gases or vapors are normally prevented by positive mechanical ventilation, and which might become hazardous through failure or abnormal operation of the ventilating equipment, or (c) That is adjacent to a Class I, Division 1 location, and to which ignitible concentrations of gases or vapors might occasionally be communicated unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air, and effective safeguards against ventilation failure are provided. FPN No. 1: This classification usually includes locations where volatile flammable liquids or flammable gases or vapors are used but that, in the judgment of the authority having jurisdiction, would become hazardous only in case of an accident or of some unusual operating

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condition. The quantity of flammable material that might escape in case of accident, the adequacy of ventilating equipment, the total area involved, and the record of the industry or business with respect to explosions or fires are all factors that merit consideration in determining the classification and extent of each location. FPN No. 2: Piping without valves, checks, meters, and similar devices would not ordinarily introduce a hazardous condition even though used for flammable liquids or gases. Depending on factors such as the quantity and size of the containers and ventilation, locations used for the storage of flammable liquids or liquefied or compressed gases in sealed containers may either be considered hazardous (classified) or nonhazardous locations. See Flammable and Combustible Liquids Code, NFPA 30-1996, and Liquefied Petroleum Gas Code, NFPA 58-1998. (c) Class II Locations Class II locations are those that are hazardous because of the presence of combustible dust. Class II locations shall include those specified in (a) and (b). (1) Class II, Division 1. A Class II, Division 1 location is a location (a) In which combustible dust is in the air under normal operating conditions in quantities sufficient to produce explosive or ignitible mixtures, or (b) Where mechanical failure or abnormal operation of machinery or equipment might cause such explosive or ignitible mixtures to be produced, and might also provide a source of ignition through simultaneous failure of electric equipment, operation of protection devices, or from other causes, or (c) In which combustible dusts of an electrically conductive nature may be present in hazardous quantities. FPN: Combustible dusts that are electrically nonconductive include dusts produced in the handling and processing of grain and grain products, pulverized sugar and cocoa, dried egg and milk powders, pulverized spices, starch and pastes, potato and wood-flour, oil meal from beans and seed, dried hay, and other organic materials that may produce combustible dusts when processed or handled. Only Group E dusts are considered to be electrically conductive for classification purposes. Dusts containing magnesium or aluminum are particularly hazardous, and the use of extreme precaution will be necessary to avoid ignition and explosion. (2) Class II, Division 2 . A Class II, Division 2 location is a location (a) Where combustible dust is not normally in the air in quantities sufficient to produce explosive or ignitible mixtures, and dust accumulations are normally insufficient to interfere with the normal operation of electrical equipment or other apparatus, but combustible dust may be in suspension in the air as a result of infrequent malfunctioning of handling or processing equipment and (b) Where combustible dust accumulations on, in, or in the vicinity of the electrical equipment may be sufficient to interfere with the safe dissipation of heat from electrical equipment or may be ignitible by abnormal operation or failure of electrical equipment. FPN No. 1: The quantity of combustible dust that may be present and the adequacy of dust removal systems are factors that merit consideration in determining the classification and may result in an nonhazardous area. FPN No. 2: Where products such as seed are handled in a manner that produces low quantities of dust, the amount of dust deposited may not warrant classification. (d) Class III Locations Class III locations are those that are hazardous because of the presence of easily ignitible fibers or flyings, but in which such fibers or flyings are not likely to be in suspension in the air in quantities sufficient to produce ignitible mixtures. Class III locations shall include those specified in (a) and (b). (1) Class III, Division 1 . A Class III, Division 1 location is a location in which easily ignitible fibers or materials producing combustible flyings are handled, manufactured, or used.

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FPN No. 1: Such locations usually include some parts of rayon, cotton, and other textile mills; combustible fiber manufacturing and processing plants; cotton gins and cotton-seed mills; flax-processing plants; clothing manufacturing plants; woodworking plants; and establishments and industries involving similar hazardous processes or conditions. FPN No. 2: Easily ignitible fibers and flyings include rayon, cotton (including cotton linters and cotton waste), sisal or henequen, istle, jute, hemp, tow, cocoa fiber, oakum, baled waste kapok, Spanish moss, excelsior, and other materials of similar nature.

(2) Class III, Division 2. A Class III, Division 2 location is a location in which easily ignitible fibers are stored or handled other than in the process of manufacture. 500-5 6 Material Groups For purposes of testing, approval, and area classification, various air mixtures (not oxygen-enriched) shall be grouped in accordance with Sections 500-56(a) and 500-5 6(b). Exception: Equipment approved for a specific gas, vapor, or dust. FPN: This grouping is based on the characteristics of the materials. Facilities are available for testing and identifying equipment for use in the various atmospheric groups. (a) Class I Group Classifications . Class I groups shall be as follows. (1) Group A. Acetylene. (2) Group B. Flammable gas, flammable liquid­produced vapor, or combustible liquid­produced vapor mixed with air that may burn or explode, having either a maximum experimental safe gap (MESG) value less than or equal to 0.45 mm or a minimum igniting current ratio (MIC ratio) less than or equal to 0.40. FPN: A typical Class I, Group B material is hydrogen.

Exception No. 1: Group D equipment shall be permitted to be used for atmospheres containing butadiene provided all conduit runs into explosionproof equipment are provided with explosionproof seals installed within 18 in. (457 mm) of the enclosure. Exception No. 2: Group C equipment shall be permitted to be used for atmospheres containing allyl glycidyl ether, n-butyl glycidyl ether, ethylene oxide, propylene oxide, and acrolein provided all conduit runs into explosionproof equipment are provided with explosionproof seals installed within 18 in. (457 mm) of the enclosure. (3) Group C. Flammable gas, flammable liquid­produced vapor, or combustible liquid­produced vapor mixed with air that may burn or explode, having either a maximum experimental safe gap (MESG) value greater than 0.45 mm and less than or equal to 0.75 mm, or a minimum igniting current ratio (MIC ratio) greater than 0.40 and less than or equal to 0.80. FPN: A typical Class I, Group C material is ethylene.

(4) Group D. Flammable gas, flammable liquid­produced vapor, or combustible liquid­produced vapor mixed with air that may burn or explode, having either a maximum experimental safe gap (MESG) value greater than 0.75 mm or a minimum igniting current ratio (MIC ratio) greater than 0.80. FPN No. 1: A typical Class I, Group D material is propane. FPN No. 2: For classification of areas involving ammonia atmosphere, see Safety Code for Mechanical Refrigeration, ANSI/ASHRAE 15-1994, and Safety Requirements for the Storage and Handling of Anhydrous Ammonia, ANSI/CGA G2.1-1989. Exception: For atmospheres containing ammonia, the authority having jurisdiction for enforcement of this Code shall be permitted to reclassify th location to reduced level of class a ification or to an unclassified less hazardous location or a nonhazardous location.(14-37) FPN No. 1: For additional information on the properties and group classification of Class I materials, see Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 497-1997, and Guide to Fire Hazard Properties of Flammable Liquids, Gases, and Volatile Solids, NFPA 325-1994.

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The following FPN 's apply to section (a): FPN No. 1: The explosion characteristics of air mixtures of gases or vapors vary with the specific material involved. For Class I locations, Groups A, B, C, and D, the classification involves determinations of maximum explosion pressure and maximum safe clearance between parts of a clamped joint in an enclosure. It is necessary, therefore, that equipment be approved not only for class but also for the specific group of the gas or vapor that will be present. FPN No. 2: Certain chemical atmospheres may have characteristics that require safeguards beyond those required for any of the above groups. Carbon disulfide is one of these chemicals because of its low ignition temperature [100ºC (212ºF)] and the small joint clearance permitted to arrest its flame. FPN No. 3: For classification of areas involving ammonia atmosphere, see Safety Code for Mechanical Refrigeration, ANSI/ASHRAE 15-1994, and Safety Requirements for the Storage and Handling of Anhydrous Ammonia, ANSI/CGA G2.1-1989. (b) Class II Group Classifications. Class II groups shall be as follows. (1) Group E. Atmospheres containing combustible metal dusts, including aluminum, magnesium, and their commercial alloys, or other combustible dusts whose particle size, abrasiveness, and conductivity present similar hazards in the use of electrical equipment. FPN: Certain metal dusts may have characteristics that require safeguards beyond those required for atmospheres containing the dusts of aluminum, magnesium, and their commercial alloys. For example, zirconium, thorium, and uranium dusts have extremely low ignition temperatures [as low as 20ºC (68ºF)] and minimum ignition energies lower than any material classified in any of the Class I or Class II Groups. (2) Group F. Atmospheres containing combustible carbonaceous dusts that have more than 8 percent total entrapped volatiles (see Standard Test Method for Volatile Material in the Analysis Sample for Coal and Coke, ASTM D3175-89, for coal and coke dusts) or that have been sensitized by other materials so that they present an explosion hazard. Coal, carbon black, charcoal, and coke dusts are examples of carbonaceous dusts. (3) Group G. Atmospheres containing combustible dusts not included in Group E or F, including flour, grain, wood, plastic, and chemicals. FPN No. 1: For additional information on group classification of Class II materials, see Recommended Practice for the Classification of Combustible Dusts and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 499-1997. FPN No. 2: The explosion characteristics of air mixtures of dust vary with the materials involved. For Class II locations, Groups E, F, and G, the classification involves the tightness of the joints of assembly and shaft openings to prevent the entrance of dust in the dust-ignitionproof enclosure, the blanketing effect of layers of dust on the equipment that may cause overheating, and the ignition temperature of the dust. It is necessary, therefore, that equipment be approved not only for the class, but also for the specific group of dust that will be present. FPN No. 3: Certain dusts may require additional precautions due to chemical phenomena that can result in the generation of ignitible gases. See National Electrical Safety Code, ANSI C2-1997, Section 127A, Coal Handling Areas. 500 -6 7 Protection Techniques The following shall be acceptable protection techniques for electrical and electronic equipment in hazardous (classified) locations. (a) Explosionproof Apparatus. This protection technique shall be permitted for equipment in Class I, Division 1 or 2 locations. (b) Dust Ignitionproof. This protection technique shall be permitted for equipment in Class II, Division 1 or 2 locations.

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(c) Dusttight. This protection technique shall be permitted for equipment in Class II, Division 2 or Class III locations. (d) Purged and Pressurized. This protection technique shall be permitted for equipment in any hazardous (classified) location for which it is approved. (e) Intrinsic Safety. This protection technique shall be permitted for equipment in Class I, Division 1 or 2, or Class II, Division 1 or 2, or Class III, Division 1 or 2 locations. The provisions of Articles 501 through 503 and 510 through 516 shall not be considered applicable to such installations, except as required by Article 504, and installation of intrinsically safe apparatus and wiring shall be in accordance with the requirements of Article 504. (f) Nonincendive Circuit. This protection technique shall be permitted for equipment in Class I, Division 2, Class II, Division 2, Class III, Division 2 locations. (g) Nonincendive Equipment. This protection technique shall be permitted for equipment in Class I, Division 2, Class II, Division 2, Class III, and Division 2 locations. (h) Nonincendive Component This protection technique shall be . permitted for equipment in Class I, Division 2, Class II, Division 2, Class III, Division 2 locations. (i) Nonincendive Component. This protection technique shall be permitted for current-interrupting contacts in those Class I, Division 2 locations for which the component is approved. (j) Oil Immersion. This protection technique shall be permitted for current-interrupting contacts in Class I, Division 2 locations as described in Section 501-67(b)(1)(b). (k) Hermetically Sealed. This protection technique shall be permitted for equipment in Class I and II, Division 2, and Class III, Division 1 and 2 locations. (l) Other Protection Techniques. Other protection techniques used in equipment listed for use in hazardous (classified) locations. 500 -7 8 Equipment Articles 500 through 504 require equipment construction and installation that will ensure safe performance under conditions of proper use and maintenance. FPN No. 1: It is important that inspection authorities and users exercise more than ordinary care with regard to installation and maintenance. FPN No. 2: Low ambient conditions require special consideration. Explosionproof or dust-ignitionproof equipment may not be suitable for use at temperatures lower than -25ºC (-13ºF) unless they are identified for low-temperature service. However, at low ambient temperatures, flammable concentrations of vapors may not exist in a location classified Class I, Division 1 at normal ambient temperature. (a) Approval for Class and Properties. (1) Equipment shall be approved not only for the class of location but also for the explosive, combustible, or ignitible properties of the specific gas, vapor, dust, fiber, or flyings that will be present. In addition, Class I equipment shall not have any exposed surface that operates at a temperature in excess of the ignition temperature of the specific gas or vapor. Class II equipment shall not have an external temperature higher than that specified in Section 50078(2). Class III equipment shall not exceed the maximum surface temperatures specified in Section 503-1. (2) Equipment that has been approved for a Division 1 location shall be permitted in a Division 2 location of the same class and group. (3) Where specifically permitted in Articles 501 through 503, general-purpose equipment or equipment in general-purpose enclosures shall be permitted to be installed in Division 2 locations if the equipment does not constitute a source of ignition under normal operating conditions. (4) Equipment, regardless of the classification of the location in which it is installed, that depends on a single compression seal, diaphragm, or tube to prevent flammable or combustible fluids from entering the equipment, shall be approved for a Class I, Division 2 location.

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Exception: Equipment installed in a Class I, Division 1 location shall be (1) Class I Temperature. The temperature marking specified in (b) suitable for the Division 1 location. shall not exceed the ignition temperature of the specific gas or FPN: See Section 501-5(f)(3) for additional vapor to be encountered. requirements. FPN: For information regarding ignition temperatures of gases and vapors, see Recommended Practice for the (5) Unless otherwise specified, normal operating conditions for Classification of flammable gases, etc. and of Hazardous motors shall be assumed to be rated full-load steady conditions. (Classified) Locations for Electrical Installations in (6) Where flammable gases or combustible dusts are or may be Chemical Process Areas, NFPA 497-1997. present at the same time, the simultaneous presence of both shall be considered when determining the safe operating temperature of (2) Class II Temperature. The temperature marking specified in the electrical equipment. (b) shall be less than the ignition temperature of the specific dust FPN: The characteristics of various atmospheric mixtures to be encountered. For organic dusts that may dehydrate or of gases, vapors, and dusts depend on the specific carbonize, the temperature marking shall not exceed the lower of material involved. either the ignition temperature or 165ºC (329ºF). FPN: See Recommended Practice for the Classification of (b) Marking. Equipment shall be marked to show the class, group, Combustible Dusts and of Hazardous (Classified) and operating temperature or temperature class range referenced Locations for Electrical Installations in Chemical Process Areas, NFPA 499-1997, for minimum ignition to a 40ºC ambient. temperatures of specific dusts. Exception No. 1: Equipment of the non-heat-producing type, such as The ignition temperature for which equipment was approved prior junction boxes, conduit, and fittings, and equipment of the heatto this requirement shall be assumed to be as shown in Table 500producing type having a maximum temperature not more than 100ºC 5(c) (2). (212ºF) shall not be required to have a marked operating temperature or Table 500-5(c) (2). temperature range class . Exception No. 2: Fixed lighting fixtures marked for use in Class I, Equipment (Such as Motors or Power Division 2 or Class II, Division 2 locations only shall not be required to Transformers) that May Be Overloaded be marked to indicate the group. Equipment that Is Exception No. 3: Fixed general-purpose equipment in Class I locations, Not Subject to Normal Abnormal other than fixed lighting fixtures, that is acceptable for use in Class I, Overloading Operation Division 2 locations shall not be required to be marked with the class, Operation group, division, or operating temperature. Class II Group ºC ºF ºC ºF Exception No. 4: Fixed dusttight equipment other than fixed lighting ºC ºF fixtures that are acceptable for use in Class II, Division 2 and Class III E 200 392 200 392 200 locations shall not be required to be marked with the class, group, 392 division, or operating temperature. F 200 392 150 302 200 Exception No. 5: Electric equipment suitable for ambient temperatures 392 exceeding 40ºC (104ºF) shall be marked with both the maximum ambient G 165 329 120 248 165 temperature and the operating temperature or temperature at class range 329 that ambient temperature. FPN: Equipment not marked to indicate a division, or (d) Threading marked "Division 1" or "Div. 1," is suitable for both All threaded conduit referred to herein shall be threaded with an Division 1 and 2 locations. Equipment marked "Division National (American) Standard Pipe Taper (NPT ) standard 2" or "Div. 2" is suitable for Division 2 locations only. conduit cutting die that provides _-in. taper per foot. Such conduit shall be made wrenchtight to prevent sparking when fault current The temperature class range, if provided, shall be indicated using flows through the conduit system, and to ensure the the temperature class (T Codes) in identification numbers, as explosionproof or flameproof integrity of the conduit system where shown in Table 500-7 8(b). applicable. The temperature class (T Code)Identification numbers marked on Equipment provided with threaded entries for field wiring equipment nameplates shall be in accordance with Table 500connections shall be installed in accordance with (1) or (2). 87(b). (1) (2) Equipment Provided with Threaded Entries for NPT Equipment that is approved for Class I and Class II shall be Threaded Conduit or Fittings. For equipment provided with marked with the maximum safe operating temperature, as threaded entries for NPT threaded conduit or fittings, listed determined by simultaneous exposure to the combinations of Class conduit, conduit fittings, or cable fittings shall be used. I and Class II conditions. FPN: Threading specifications for NPT threads are FPN: Since there is no consistent relationship between located in Pipe Threads, General Purpose (Inch), explosion properties and ignition temperature, the two ANSI/ASME B1.20.1-1983. are independent requirements. (2) Equipment Provided with Threaded Entries for Metric Table 500-8( b ). Classification of Maximum Surface Temperature Threaded Conduit or Fittings. For equipment with metric threaded Identification Numbers entries, such entries shall be identified as being metric, or listed adapters to permit connection to conduit or NPT-threaded fittings Maximum Identification Temperature shall be provided with the equipment. Adapters shall be used for connection to conduit or NPT-threaded fittings. Listed cable Temperature NumberClass (T Code) fittings that have metric threads shall be permitted to be used. ºC ºF 450 842 T1 FPN: Threading specifications for metric threaded 300 572 T2 entries are located in Metric Screw Threads, ISO 280 536 T2A 965/1:1980, and Metric Screw Threads, ISO 965/3:1980. 260 500 T2B 230 446 T2C 215 419 T2D (e) Fiber Optic Cable Assembly. 200 392 T3 Where a fiber optic cable assembly contains conductors that are capable of carrying current, the fiber optic cable assembly shall be 180 356 T3A installed in accordance with the requirements of Articles 500, 501, 165 329 T3B 502, or 503, as applicable. 160 320 T3C 135 275 T4 500-9. Specific Occupancies 120 248 T4A Articles 510 through 517 cover garages, aircraft hangars, gasoline 100 212 T5 dispensing and service stations, bulk storage plants, spray 85 185 T6 application, dipping and coating processes, and health care facilities. (c) Temperature ___________________

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(Log #2128) 14- 3 - (500): Accept in Principle SUBMITTER: Kari Barrett, Chemical Manufacturers Assn. RECOMMENDATION: Reorganize Article 500 as indicated below per NEC CMA Proposal 14-1. With the exception of minor titling changes and a rearrangement of sentences as indicated within one section, this proposal contains no new words, concepts or requirements. Revise Article 500 as follows: 1) Relocate 500-3 (a) as 500- 4 (a) and renumber 500-3 with existing 500 -3 (b) (c) section. Relocate 500-3 (d) and 500 -3 (e) to new sections under 500-7. With change: 500-3 General. (a) Documentation All areas designated as hazardous (classified) . locations shall be properly documented. This documentation shall be available to those authorized to design, install, inspect, maintain, or operate electrical equipment at the location. (b) Reference Standards. FPN No. 1: It is important that the authority having jurisdiction be familiar with recorded industrial experience as well as with the standards of the National Fire Protection Association, the American Petroleum Institute, and the Instrument Society of America that may be of use in the classification of various locations, the determination of adequate ventilation, and the protection against static electricity and lightning hazards. FPN No. 2: For further information on the classification of locations, see Flammable and Combustible Liquids Code, NFPA 30-1996; Standard for Drycleaning Plants, NFPA 32-1996; Standard for Spray Application Using Flammable or Combustible Materials, NFPA 33-1995; Standard for Dipping and Coating Processes Using Flammable or Combustible Liquids, NFPA 34-1995; Standard for the Manufacture of Organic Coatings, NFPA 35-1995; Standard for Solvent Extraction Plants, NFPA 361997; Standard on Fire Protection for Laboratories Using Chemicals, NFPA 45-1996; Standard for Gaseous Hydrogen Systems at Consumer Sites, NFPA 50A-1994; Standard for Liquefied Hydrogen Systems at Consumer Sites, NFPA 50B-1994; Liquefied Petroleum Gas Code, NFPA 58-1998; Standard for the Storage and Handling of Liquefied Petroleum Gases at Utility Gas Plants, NFPA 59-1998; Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 497-1997; Recommended Practice for the Classification of Combustible Dusts and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 499-1997; Standard for Fire Protection in Wastewater Treatment and Collection Facilities, NFPA 820-1995; Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Division 1 and Division 2, ANSI/API RP500-1997; Area Classification In Hazardous (Classified) Dust Locations, ANSI/ISA-S12.10-1988. FPN No. 3: For further information on protection against static electricity and lightning hazards in hazardous (classified) locations, see Recommended Practice on Static Electricity, NFPA 77-1993; Standard for the Installation of Lightning Protection Systems, NFPA 7801997; and Protection Against Ignitions Arising Out of Static Lightning and Stray Currents, API RP 2003-1991. FPN No. 4: For further information on ventilation, see Flammable and Combustible Liquids Code, NFPA 301996; and Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Division 1 and Division 2, API RP 500-1997, Section 4.6. FPN No. 5: For further information on electrical systems for hazardous (classified) locations on offshore oil and gas producing platforms, see Recommended Practice for Design and Installation of Electrical Systems for Offshore Production Platforms, ANSI/API RP 14F-1991.

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2) Move the entire sections 500-7, 500-8 and 500- 9 under new 500 4: this will result in a discussion of the classification of locations all under a single new titled section as follows: With change: 500-4. Classifications of Locations. (a) Classifications of Locations. Locations shall be classified depending on the properties of the flammable vapors, liquids, or gases, or combustible dusts or fibers that may be present and the likelihood that a flammable or combustible concentration or quantity is present. Where pyrophoric materials are the only materials used or handled, these locations shall not be classified. Each room, section, or area shall be considered individually in determining its classification. FPN: Through the exercise of ingenuity in the layout of electrical installations for hazardous (classified) locations, it is frequently possible to locate much of the equipment in less hazardous or in nonhazardous locations and, thus, to reduce the amount of special equipment required. (b) Class I Locations(500-7.) Class I locations are those in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitible mixtures. Class I locations shall include those specified in (1) and (2). (1) Class I, Division 1. A Class I, Division 1 location is a location (a) In which ignitible concentrations of flammable gases or vapors can exist under normal operating conditions, or (b) In which ignitible concentrations of such gases or vapors may exist frequently because of repair or maintenance operations or because of leakage, or (c) In which breakdown or faulty operation of equipment or processes might release ignitible concentrations of flammable gases or vapors, and might also cause simultaneous failure of electrical equipment in such a way as to directly cause the electrical equipment to become a source of ignition. FPN No. 1: This classification usually includes the following locations: a. Where volatile flammable liquids or liquefied flammable gases are transferred from one container to another b. Interiors of spray booths and areas in the vicinity of spraying and painting operations where volatile flammable solvents are used c. Locations containing open tanks or vats of volatile flammable liquids d. Drying rooms or compartments for the evaporation of flammable solvents e. Locations containing fat and oil extraction equipment using volatile flammable solvents f. Portions of cleaning and dyeing plants where flammable liquids are used g. Gas generator rooms and other portions of gas manufacturing plants where flammable gas may escape h. Inadequately ventilated pump rooms for flammable gas or for volatile flammable liquids i. The interiors of refrigerators and freezers in which volatile flammable materials are stored in open, lightly stoppered, or easily ruptured containers j. All other locations where ignitible concentrations of flammable vapors or gases are likely to occur in the course of normal operations. FPN No. 2: In some Division 1 locations, ignitible concentrations of flammable gases or vapors may be present continuously or for long periods of time. Examples include the following: a. The inside of inadequately vented enclosures containing instruments normally venting flammable gases or vapors to the interior of the enclosure b. The inside of vented tanks containing volatile flammable liquids c. The area between the inner and outer roof sections of a floating roof tank containing volatile flammable fluids

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d. Inadequately ventilated areas within spraying or coating operations using volatile flammable fluids e. The interior of an exhaust duct that is used to vent ignitible concentrations of gases or vapors. Experience has demonstrated the prudence of avoiding the installation of instrumentation or other electric equipment in these particular areas altogether or where it cannot be avoided because it is essential to the process and other locations are not feasible [see Section 500-4(a), FPN], using electric equipment or instrumentation approved for the specific application or consisting of intrinsically safe systems as described in Article 504. (2) Class I, Division 2. A Class I, Division 2 location is a location (a) In which volatile flammable liquids or flammable gases are handled, processed, or used, but in which the liquids, vapors, or gases will normally be confined within closed containers or closed systems from which they can escape only in case of accidental rupture or breakdown of such containers or systems, or in case of abnormal operation of equipment, or (b) In which ignitible concentrations of gases or vapors are normally prevented by positive mechanical ventilation, and which might become hazardous through failure or abnormal operation of the ventilating equipment, or (c) That is adjacent to a Class I, Division 1 location, and to which ignitible concentrations of gases or vapors might occasionally be communicated unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air, and effective safeguards against ventilation failure are provided. FPN No. 1: This classification usually includes locations where volatile flammable liquids or flammable gases or vapors are used but that, in the judgment of the authority having jurisdiction, would become hazardous only in case of an accident or of some unusual operating condition. The quantity of flammable material that might escape in case of accident, the adequacy of ventilating equipment, the total area involved, and the record of the industry or business with respect to explosions or fires are all factors that merit consideration in determining the classification and extent of each location. FPN No. 2: Piping without valves, checks, meters, and similar devices would not ordinarily introduce a hazardous condition even though used for flammable liquids or gases. Depending on factors such as the quantity and size of the containers and ventilation, locations used for the storage of flammable liquids or liquefied or compressed gases in sealed containers may either be considered hazardous (classified) or nonhazardous locations. See Flammable and Combustible Liquids Code, NFPA 30-1996, and Liquefied Petroleum Gas Code, NFPA 58-1998. (c) Class II Locations. Class II locations are those that are hazardous because of the presence of combustible dust. Class II locations shall include those specified in (a) and (b). (1) Class II, Division 1. A Class II, Division 1 location is a location (a) In which combustible dust is in the air under normal operating conditions in quantities sufficient to produce explosive or ignitible mixtures, or (b) Where mechanical failure or abnormal operation of machinery or equipment might cause such explosive or ignitible mixtures to be produced, and might also provide a source of ignition through simultaneous failure of electric equipment, operation of protection devices, or from other causes, or (c) In which combustible dusts of an electrically conductive nature may be present in hazardous quantities. FPN: Combustible dusts that are electrically nonconductive include dusts produced in the handling and processing of grain and grain products, pulverized sugar and cocoa, dried egg and milk powders, pulverized spices, starch and pastes, potato and wood-flour, oil meal from beans and seed, dried hay, and other organic materials that may produce combustible dusts when processed or handled. Only Group E dusts are considered to be electrically conductive for classification purposes. Dusts containing magnesium or aluminum are particularly hazardous, and the use of extreme

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precaution will be necessary to avoid ignition and explosion.

(2) Class II, Division 2. A Class II, Division 2 location is a location (a) Where combustible dust is not normally in the air in quantities sufficient to produce explosive or ignitible mixtures, and dust accumulations are normally insufficient to interfere with the normal operation of electrical equipment or other apparatus, but combustible dust may be in suspension in the air as a result of infrequent malfunctioning of handling or processing equipment and (b) Where combustible dust accumulations on, in, or in the vicinity of the electrical equipment may be sufficient to interfere with the safe dissipation of heat from electrical equipment or may be ignitible by abnormal operation or failure of electrical equipment. FPN No. 1: The quantity of combustible dust that may be present and the adequacy of dust removal systems are factors that merit consideration in determining the classification and may result in an nonhazardous area. FPN No. 2: Where products such as seed are handled in a manner that produces low quantities of dust, the amount of dust deposited may not warrant classification. (d) Class III Locations. Class III locations are those that are hazardous because of the presence of easily ignitible fibers or flyings, but in which such fibers or flyings are not likely to be in suspension in the air in quantities sufficient to produce ignitible mixtures. Class III locations shall include those specified in (a) and (b). (1) Class III, Division 1 . A Class III, Division 1 location is a location in which easily ignitible fibers or materials producing combustible flyings are handled, manufactured, or used. FPN No. 1: Such locations usually include some parts of rayon, cotton, and other textile mills; combustible fiber manufacturing and processing plants; cotton gins and cotton-seed mills; flax-processing plants; clothing manufacturing plants; woodworking plants; and establishments and industries involving similar hazardous processes or conditions. FPN No. 2: Easily ignitible fibers and flyings include rayon, cotton (including cotton linters and cotton waste), sisal or henequen, istle, jute, hemp, tow, cocoa fiber, oakum, baled waste kapok, Spanish moss, excelsior, and other materials of similar nature. (2) Class III, Division 2. A Class III, Division 2 location is a location in which easily ignitible fibers are stored or handled other than in the process of manufacture. 3) Provide new 500 -5 consisting of existing sections 500-5 (a) (b) and (c) 500-5 Material Groups. For purposes of testing, approval, and area classification, various air mixtures (not oxygen-enriched) shall be grouped in accordance with Sections 500-5(a) and 500-5(b). Exception: Equipment approved for a specific gas, vapor, or dust. FPN: This grouping is based on the characteristics of the materials. Facilities are available for testing and identifying equipment for use in the various atmospheric groups. (a) Class I Group Classifications. Class I groups shall be as follows. (1) Group A. Acetylene. (2) Group B. Flammable gas, flammable liquid­produced vapor, or combustible liquid­produced vapor mixed with air that may burn or explode, having either a maximum experimental safe gap (MESG) value less than or equal to 0.45 mm or a minimum igniting current ratio (MIC ratio) less than or equal to 0.40. FPN: A typical Class I, Group B material is hydrogen.

Exception No. 1: Group D equipment shall be permitted to be used for atmospheres containing butadiene provided all conduit runs into explosionproof equipment are provided with explosionproof seals installed within 18 in. (457 mm) of the enclosure.

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Exception No. 2: Group C equipment shall be permitted to be used for atmospheres containing allyl glycidyl ether, n-butyl glycidyl ether, ethylene oxide, propylene oxide, and acrolein provided all conduit runs into explosionproof equipment are provided with explosionproof seals installed within 18 in. (457 mm) of the enclosure. (3) Group C. Flammable gas, flammable liquid­produced vapor, or combustible liquid­produced vapor mixed with air that may burn or explode, having either a maximum experimental safe gap (MESG) value greater than 0.45 mm and less than or equal to 0.75 mm, or a minimum igniting current ratio (MIC ratio) greater than 0.40 and less than or equal to 0.80. FPN: A typical Class I, Group C material is ethylene.

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Practice for the Classification of Combustible Dusts and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 499-1997. FPN No. 2: The explosion characteristics of air mixtures of dust vary with the materials involved. For Class II locations, Groups E, F, and G, the classification involves the tightness of the joints of assembly and shaft openings to prevent the entrance of dust in the dust-ignitionproof enclosure, the blanketing effect of layers of dust on the equipment that may cause overheating, and the ignition temperature of the dust. It is necessary, therefore, that equipment be approved not only for the class, but also for the specific group of dust that will be present.

(4) Group D. Flammable gas, flammable liquid­produced vapor, or combustible liquid­produced vapor mixed with air that may FPN No. 3: Certain dusts may require additional burn or explode, having either a maximum experimental safe gap precautions due to chemical phenomena that can result (MESG) value greater than 0.75 mm or a minimum igniting current in the generation of ignitible gases. See National ratio (MIC ratio) greater than 0.80. Electrical Safety Code, ANSI C2-1997, Section 127A, Coal FPN: A typical Class I, Group D material is propane. Handling Areas. Exception: For atmospheres containing ammonia, the authority having jurisdiction for enforcement of this Code shall be permitted to reclassify 5) Renumber 500-4 as 500-6. the location to a less hazardous location or a nonhazardous location. FPN No. 1: For additional information on the properties With change: and group classification of Class I materials, see Recommended Practice for the Classification of 500 -6 Protection Techniques. The following shall be acceptable Flammable Liquids, Gases, or Vapors and of Hazardous protection techniques for electrical and electronic equipment in (Classified) Locations for Electrical Installations in hazardous (classified) locations. Chemical Process Areas, NFPA 497-1997, and Guide to (a) Explosionproof Apparatus. This protection technique shall be Fire Hazard Properties of Flammable Liquids, Gases, permitted for equipment in those Class I, Division 1 and 2 and Volatile Solids, NFPA 325-1994. locations for which it is approved. FPN No. 2: The explosion characteristics of air mixtures FPN: Explosionproof apparatus is defined in Article 100. of gases or vapors vary with the specific material involved. For further information, see Explosionproof and DustFor Class I locations, Groups A, B, C, and D, the Ignitionproof Electrical Equipment for Use in Hazardous classification involves determinations of maximum (Classified) Locations, ANSI/UL 1203-1994. explosion pressure and maximum safe clearance between parts of a clamped joint in an enclosure. It is necessary, (b) Dust Ignitionproof. This protection technique shall be therefore, that equipment be approved not only for class permitted for equipment in those Class II, Division 1 and 2 but also for the specific group of the gas or vapor that locations for which it is approved. will be present. FPN: Dust-ignitionproof equipment is defined in Article FPN No. 3: Certain chemical atmospheres may have 100. For further information, see Explosionproof and characteristics that require safeguards beyond those Dust-Ignitionproof Electrical Equipment for Use in required for any of the above groups. Carbon disulfide is Hazardous (Classified) Locations, ANSI/UL 1203-1994. one of these chemicals because of its low ignition temperature [100ºC (212ºF)] and the small joint (c) Dusttight. This protection technique shall be permitted for clearance permitted to arrest its flame. equipment in those Class II, Division 2 and Class III locations for FPN No. 4: For classification of areas involving ammonia which it is approved. atmosphere, see Safety Code for Mechanical FPN No. 1: Dusttight enclosures are constructed so that Refrigeration, ANSI/ASHRAE 15-1994, and Safety dust will not enter the enclosing cases under specified Requirements for the Storage and Handling of test conditions. Anhydrous Ammonia, ANSI/CGA G2.1-1989. FPN No. 2: For further information, see Nonincendive Electrical Equipment for Use in Class I and II, Division (b) Class II Group Classifications. Class II groups shall be as 2, and Class III, Divisions 1 and 2 Hazardous (Classified) follows. Locations, ANSI/ISA S12.12-1994, and Electrical Equipment for Use in Class I and II, Division 2 and Class (1) Group E. Atmospheres containing combustible metal dusts, III Hazardous (Classified) Locations, UL 1604-1994. including aluminum, magnesium, and their commercial alloys, or FPN No. 3: For further information on test conditions other combustible dusts whose particle size, abrasiveness, and for equipment other than rotating equipment, see conductivity present similar hazards in the use of electrical Enclosures for Electrical Equipment (1000 volts equipment. Maximum), ANSI/NEMA 250-1991. (d) Purged and Pressurized. This protection technique shall be FPN: Certain metal dusts may have characteristics that permitted for equipment in any hazardous (classified) location for require safeguards beyond those required for which it is approved. atmospheres containing the dusts of aluminum, FPN No. 1: In some cases, hazards may be reduced or magnesium, and their commercial alloys. For example, hazardous (classified) locations limited or eliminated by zirconium, thorium, and uranium dusts have extremely adequate positive-pressure ventilation from a source of low ignition temperatures [as low as 20ºC (68ºF)] and clean air in conjunction with effective safeguards against minimum ignition energies lower than any material ventilation failure. classified in any of the Class I or Class II Groups. FPN No. 2: For further information, see Standard for Purged and Pressurized Enclosures for Electrical (2) Group F. Atmospheres containing combustible carbonaceous Equipment, NFPA 496-1998. dusts that have more than 8 percent total entrapped volatiles (see (e) Intrinsically Safe Systems . Intrinsically safe apparatus and Standard Test Method for Volatile Material in the Analysis Sample wiring shall be permitted in any hazardous (classified) location for for Coal and Coke, ASTM D3175-89, for coal and coke dusts) or which it is approved, and the provisions of Articles 501 through 503 that have been sensitized by other materials so that they present an and 510 through 516 shall not be considered applicable to such explosion hazard. Coal, carbon black, charcoal, and coke dusts are installations, except as required by Article 504. examples of carbonaceous dusts. Installation of intrinsically safe apparatus and wiring shall be in accordance with the requirements of Article 504. (3) Group G. Atmospheres containing combustible dusts not FPN: For further information, see Intrinsically Safe included in Group E or F, including flour, grain, wood, plastic, Apparatus and Associated Apparatus for Use in Class I, and chemicals. II, and III, Division 1, Hazardous Locations, ANSI/UL FPN No. 1: For additional information on group 913-1997. classification of Class II materials, see Recommended

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(f) Nonincendive. A protective technique where, under normal operating conditions, any arcing or thermal effects are not capable of igniting the flammable gas, vapor, or dust-in-air mixture. This protection technique shall be permitted for equipment in those Class I, Division 2; Class II, Division 2; and Class III locations for which it is approved. (1) Nonincendive Circuit. A circuit in which any arc or thermal effect produced, under intended operating conditions of the equipment or due to opening, shorting, or grounding of field wiring, is not capable, under specified test conditions, of igniting the flammable gas­, vapor­, or dust­air mixture. FPN No. 1: For test conditions, see Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Division 1 and 2 Hazardous (Classified) Locations, ANSI/ISA S12.12-1994. FPN No. 2: Nonincendive circuit is defined in Article 100. For further information, see Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Division 1 and 2 Hazardous (Classified) Locations, ANSI/ISA S12.12-1994. (2) Nonincendive Equipment. Equipment having electrical/electronic circuitry that is incapable, under normal operating conditions, of causing ignition of a specified flammable gas­, vapor­, or dust­air mixture due to arcing or thermal means. FPN: For further information, see Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1 and 2 Hazardous (Classified) Locations, ANSI/ISA-S12.12-1994. (3) Nonincendive Component. A component having contacts for making or breaking an incendive circuit and the contacting mechanism shall be constructed so that the component is incapable of igniting the specified flammable gas­ or vapor­air mixture. The housing of a nonincendive component is not intended to exclude the flammable atmosphere or contain an explosion. This protection technique shall be permitted for currentinterrupting contacts in those Class I, Division 2 locations for which the component is approved. FPN: For further information, see Electrical Equipment for Use in Class I and II, Division 2, and Class III Hazardous (Classified) Locations, UL 1604-1994. (g) Oil Immersion. This protection technique shall be permitted for current-interrupting contacts in Class I, Division 2 locations as described in Section 501-6(b)(1)(b). FPN: See Sections 501-3(b)(1), Exception (a); 5015(a)(1), Exception (b), 501-6(b)(1); 501-14(b)(1), Exception (a); 502-14(a)(2), Exception; and 50214(a)(3), Exception. For further information, see Industrial Control Equipment for Use in Hazardous (Classified) Locations, ANSI/UL 698-1995. (h) Hermetically Sealed. A hermetically sealed device shall be sealed against the entrance of an external atmosphere and the seal shall be made by fusion, e.g., soldering, brazing, welding, or the fusion of glass to metal. This protection technique shall be permitted for currentinterrupting contacts in Class I, Division 2 locations. FPN: See Sections 501-3(b)(1), Exception (b); 5015(a)(1), Exception (a); 501-6(b)(1)(a); and 50114(b)(1), Exception (b). For further information, see Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Division 1 and 2 Hazardous (Classified) Locations, ANSI/ISA S12.121994. (i) Other Protection Techniques. Other protection techniques used in equipment listed for use in hazardous (classified) locations. 4) Renumber 500-5 and 500-7, change the order of paragraphs in 500-5(c) and insert it as new 500-7 (a). With change: 500 -7 Equipment. Articles 500 through 504 require equipment construction and installation that will ensure safe performance under conditions of proper use and maintenance. FPN No. 1: It is important that inspection authorities and users exercise more than ordinary care with regard to installation and maintenance. FPN No. 2: Low ambient conditions require special consideration. Explosionproof or dust-ignitionproof equipment may not be suitable for use at temperatures lower than -25ºC (-13ºF) unless they are identified for low-temperature service. However, at low ambient

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temperatures, flammable concentrations of vapors may not exist in a location classified Class I, Division 1 at normal ambient temperature.

(a) Approval for Class and Properties. (1) Equipment shall be approved not only for the class of location but also for the explosive, combustible, or ignitible properties of the specific gas, vapor, dust, fiber, or flyings that will be present. In addition, Class I equipment shall not have any exposed surface that operates at a temperature in excess of the ignition temperature of the specific gas or vapor. Class II equipment shall not have an external temperature higher than that specified in Section 500-7(2). Class III equipment shall not exceed the maximum surface temperatures specified in Section 503-1. (2) Equipment that has been approved for a Division 1 location shall be permitted in a Division 2 location of the same class and group. (3) Where specifically permitted in Articles 501 through 503, general-purpose equipment or equipment in general-purpose enclosures shall be permitted to be installed in Division 2 locations if the equipment does not constitute a source of ignition under normal operating conditions. (4) Equipment, regardless of the classification of the location in which it is installed, that depends on a single compression seal, diaphragm, or tube to prevent flammable or combustible fluids from entering the equipment, shall be approved for a Class I, Division 2 location. Exception: Equipment installed in a Class I, Division 1 location shall be suitable for the Division 1 location. FPN: See Section 501-5(f)(3) for additional requirements. (5) Unless otherwise specified, normal operating conditions for motors shall be assumed to be rated full-load steady conditions. (6) Where flammable gases or combustible dusts are or may be present at the same time, the simultaneous presence of both shall be considered when determining the safe operating temperature of the electrical equipment. FPN: The characteristics of various atmospheric mixtures of gases, vapors, and dusts depend on the specific material involved. (b) Marking. Approved equipment shall be marked to show the class, group, and operating temperature or temperature range referenced to a 40ºC ambient. Exception No. 1: Equipment of the non-heat-producing type, such as junction boxes, conduit, and fittings, and equipment of the heatproducing type having a maximum temperature not more than 100ºC (212ºF) shall not be required to have a marked operating temperature or temperature range. Exception No. 2: Fixed lighting fixtures marked for use in Class I, Division 2 or Class II, Division 2 locations only shall not be required to be marked to indicate the group. Exception No. 3: Fixed general-purpose equipment in Class I locations, other than fixed lighting fixtures, that is acceptable for use in Class I, Division 2 locations shall not be required to be marked with the class, group, division, or operating temperature. Exception No. 4: Fixed dusttight equipment other than fixed lighting fixtures that are acceptable for use in Class II, Division 2 and Class III locations shall not be required to be marked with the class, group, division, or operating temperature. Exception No. 5: Electric equipment suitable for ambient temperatures exceeding 40ºC (104ºF) shall be marked with both the maximum ambient temperature and the operating temperature or temperature range at that ambient temperature. FPN: Equipment not marked to indicate a division, or marked "Division 1" or "Div. 1," is suitable for both Division 1 and 2 locations. Equipment marked "Division 2" or "Div. 2" is suitable for Division 2 locations only. The temperature range, if provided, shall be indicated in identification numbers, as shown in Table 500-7(b). Identification numbers marked on equipment nameplates shall be in accordance with Table 500-7(b). Equipment that is approved for Class I and Class II shall be marked with the maximum safe operating temperature, as determined by simultaneous exposure to the combinations of Class I and Class II conditions. FPN: Since there is no consistent relationship between explosion properties and ignition temperature, the two are independent requirements.

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Table 500-5(d). Identification Numbers Maximum Temperature Identification ºC ºF Number 450 842 T1 300 572 T2 280 536 T2A 260 500 T2B 230 446 T2C 215 419 T2D 200 392 T3 180 356 T3A 165 329 T3B 160 320 T3C 135 275 T4 120 248 T4A 100 212 T5 85 185 T6 (c) Temperature. (1) Class I Temperature. The temperature marking specified in (b) shall not exceed the ignition temperature of the specific gas or vapor to be encountered. FPN: For information regarding ignition temperatures of gases and vapors, see Recommended Practice for the Classification of Combustible Dusts and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 499-1997, and Guide to Fire Hazard Properties of Flammable Liquids, Gases, and Volatile Solids, NFPA 325-1994. (2) Class II Temperature. The temperature marking specified in (b) shall be less than the ignition temperature of the specific dust to be encountered. For organic dusts that may dehydrate or carbonize, the temperature marking shall not exceed the lower of either the ignition temperature or 165ºC (329ºF). FPN: See Recommended Practice for the Classification of Combustible Dusts and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 499-1997, for minimum ignition temperatures of specific dusts. The ignition temperature for which equipment was approved prior to this requirement shall be assumed to be as shown in Table 5005(f).

Table 500-5(f). Equipment (Such as Motors or Power Transformers) that May Be Overloaded Normal Abnormal Operation Operation ºC 200 150 120 ºF 392 302 248 ºC 200 200 165 ºF 392 392 329

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bulk storage plants, spray application, dipping and coating processes, and health care facilities. Entire 500 with recommended changes would appear as follows: ARTICLE 500 ­Hazardous (Classified) Locations, Classes I, II, and III, Divisions 1 and 2 500-1. Scope -- Articles 500 through 504. Articles 500 through 504 cover the requirements for electrical and electronic equipment and wiring for all voltages in Class I, Divisions 1 and 2; Class II, Divisions 1 and 2; and Class III, Divisions 1 and 2 locations where fire or explosion hazards may exist due to flammable gases or vapors, flammable liquids, combustible dust, or ignitible fibers or flyings. FPN: For the requirements for electrical and electronic equipment and wiring for all voltages in Class I, Zone 0, Zone 1, and Zone 2 hazardous (classified) locations where fire or explosion hazards may exist due to flammable gases or vapors, or flammable liquids, refer to Article 505. 500-2. Other Articles. Except as modified in Articles 500 through 504, all other applicable rules contained in this Code shall apply to electrical equipment and wiring installed in hazardous (classified) locations. 500-3 General (a) Documentation All areas designated as hazardous (classified) . locations shall be properly documented. This documentation shall be available to those authorized to design, install, inspect, maintain, or operate electrical equipment at the location. (b) Reference Standards. FPN No. 1: It is important that the authority having jurisdiction be familiar with recorded industrial experience as well as with the standards of the National Fire Protection Association, the American Petroleum Institute, and the Instrument Society of America that may be of use in the classification of various locations, the determination of adequate ventilation, and the protection against static electricity and lightning hazards. FPN No. 2: For further information on the classification of locations, see Flammable and Combustible Liquids Code, NFPA 30-1996; Standard for Drycleaning Plants, NFPA 32-1996; Standard for Spray Application Using Flammable or Combustible Materials, NFPA 33-1995; Standard for Dipping and Coating Processes Using Flammable or Combustible Liquids, NFPA 34-1995; Standard for the Manufacture of Organic Coatings, NFPA 35-1995; Standard for Solvent Extraction Plants, NFPA 361997; Standard on Fire Protection for Laboratories Using Chemicals, NFPA 45-1996; Standard for Gaseous Hydrogen Systems at Consumer Sites, NFPA 50A-1994; Standard for Liquefied Hydrogen Systems at Consumer Sites, NFPA 50B-1994; Liquefied Petroleum Gas Code, NFPA 58-1998; Standard for the Storage and Handling of Liquefied Petroleum Gases at Utility Gas Plants, NFPA 59-1998; Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 497-1997; Recommended Practice for the Classification of Combustible Dusts and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 499-1997; Standard for Fire Protection in Wastewater Treatment and Collection Facilities, NFPA 820-1995; Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Division 1 and Division 2, ANSI/API RP500-1997; Area Classification In Hazardous (Classified) Dust Locations, ANSI/ISA-S12.10-1988. FPN No. 3: For further information on protection against static electricity and lightning hazards in hazardous (classified) locations, see Recommended Practice on Static Electricity, NFPA 77-1993; Standard for the Installation of Lightning Protection Systems, NFPA 7801997; and Protection Against Ignitions Arising Out of Static Lightning and Stray Currents, API RP 2003-1991. FPN No. 4: For further information on ventilation, see Flammable and Combustible Liquids Code, NFPA 301996; and Recommended Practice for Classification of

Equipment that Is Not Subject to Overloading Class II Group E F G ºC 200 200 165 ºF 392 392 329

d) Threaded Conduit. All threaded conduit referred to herein shall be threaded with an NPT standard conduit cutting die that provides _-in. taper per foot. Such conduit shall be made wrenchtight to prevent sparking when fault current flows through the conduit system, and ensure the explosionproof or dustignitionproof integrity of the conduit system where applicable. For equipment provided with metric threaded entries, such entries shall be identified as being metric, or listed adapters to permit connection to conduit or NPT-threaded fittings shall be provided with the equipment. Adapters shall be used for connection to conduit or NPT-threaded fittings. Listed cable fittings that have metric threads shall be permitted to be used. FPN: Threading specifications for metric threaded entries are located in Metric Screw Threads, ISO 965/1:1980 and Metric Screw Threads, ISO 965/3:1980. (e) Fiber Optic Cable Assembly. Where a fiber optic cable assembly contains conductors that are capable of carrying current, the fiber optic cable assembly shall be installed in accordance with the requirements of Articles 500, 501, 502, or 503, as applicable. 6) Renumber 500-6 to 500 -8 With change: 500-8. Specific Occupancies. Articles 510 through 517 cover garages, aircraft hangars, gasoline dispensing and service stations,

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Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Division 1 and Division 2, API RP 500-1997, Section 4.6. FPN No. 5: For further information on electrical systems for hazardous (classified) locations on offshore oil and gas producing platforms, see Recommended Practice for Design and Installation of Electrical Systems for Offshore Production Platforms, ANSI/API RP 14F-1991. 500-4. Classifications of Locations. (a) Classifications of Locations. Locations shall be classified depending on the properties of the flammable vapors, liquids, or gases, or combustible dusts or fibers that may be present and the likelihood that a flammable or combustible concentration or quantity is present. Where pyrophoric materials are the only materials used or handled, these locations shall not be classified. Each room, section, or area shall be considered individually in determining its classification. FPN: Through the exercise of ingenuity in the layout of electrical installations for hazardous (classified) locations, it is frequently possible to locate much of the equipment in less hazardous or in nonhazardous locations and, thus, to reduce the amount of special equipment required. (b) Class I Locations. Class I locations are those in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitible mixtures. Class I locations shall include those specified in (1) and (2). (1) Class I, Division 1. A Class I, Division 1 location is a location (a) In which ignitible concentrations of flammable gases or vapors can exist under normal operating conditions, or (b) In which ignitible concentrations of such gases or vapors may exist frequently because of repair or maintenance operations or because of leakage, or (c) In which breakdown or faulty operation of equipment or processes might release ignitible concentrations of flammable gases or vapors, and might also cause simultaneous failure of electrical equipment in such a way as to directly cause the electrical equipment to become a source of ignition. FPN No. 1: This classification usually includes the following locations: a. Where volatile flammable liquids or liquefied flammable gases are transferred from one container to another b. Interiors of spray booths and areas in the vicinity of spraying and painting operations where volatile flammable solvents are used c. Locations containing open tanks or vats of volatile flammable liquids d. Drying rooms or compartments for the evaporation of flammable solvents e. Locations containing fat and oil extraction equipment using volatile flammable solvents f. Portions of cleaning and dyeing plants where flammable liquids are used g. Gas generator rooms and other portions of gas manufacturing plants where flammable gas may escape h. Inadequately ventilated pump rooms for flammable gas or for volatile flammable liquids i. The interiors of refrigerators and freezers in which volatile flammable materials are stored in open, lightly stoppered, or easily ruptured containers j. All other locations where ignitible concentrations of flammable vapors or gases are likely to occur in the course of normal operations. FPN No. 2: In some Division 1 locations, ignitible concentrations of flammable gases or vapors may be present continuously or for long periods of time. Examples include the following: a. The inside of inadequately vented enclosures containing instruments normally venting flammable gases or vapors to the interior of the enclosure b. The inside of vented tanks containing volatile flammable liquids c. The area between the inner and outer roof sections of a floating roof tank containing volatile flammable fluids

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d. Inadequately ventilated areas within spraying or coating operations using volatile flammable fluids e. The interior of an exhaust duct that is used to vent ignitible concentrations of gases or vapors. Experience has demonstrated the prudence of avoiding the installation of instrumentation or other electric equipment in these particular areas altogether or where it cannot be avoided because it is essential to the process and other locations are not feasible [see Section 500-4(a), FPN], using electric equipment or instrumentation approved for the specific application or consisting of intrinsically safe systems as described in Article 504. (2) Class I, Division 2. A Class I, Division 2 location is a location (a) In which volatile flammable liquids or flammable gases are handled, processed, or used, but in which the liquids, vapors, or gases will normally be confined within closed containers or closed systems from which they can escape only in case of accidental rupture or breakdown of such containers or systems, or in case of abnormal operation of equipment, or (b) In which ignitible concentrations of gases or vapors are normally prevented by positive mechanical ventilation, and which might become hazardous through failure or abnormal operation of the ventilating equipment, or (c) That is adjacent to a Class I, Division 1 location, and to which ignitible concentrations of gases or vapors might occasionally be communicated unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air, and effective safeguards against ventilation failure are provided. FPN No. 1: This classification usually includes locations where volatile flammable liquids or flammable gases or vapors are used but that, in the judgment of the authority having jurisdiction, would become hazardous only in case of an accident or of some unusual operating condition. The quantity of flammable material that might escape in case of accident, the adequacy of ventilating equipment, the total area involved, and the record of the industry or business with respect to explosions or fires are all factors that merit consideration in determining the classification and extent of each location. FPN No. 2: Piping without valves, checks, meters, and similar devices would not ordinarily introduce a hazardous condition even though used for flammable liquids or gases. Depending on factors such as the quantity and size of the containers and ventilation, locations used for the storage of flammable liquids or liquefied or compressed gases in sealed containers may either be considered hazardous (classified) or nonhazardous locations. See Flammable and Combustible Liquids Code, NFPA 30-1996, and Liquefied Petroleum Gas Code, NFPA 58-1998. (c) Class II Locations. Class II locations are those that are hazardous because of the presence of combustible dust. Class II locations shall include those specified in (a) and (b). (1) Class II, Division 1. A Class II, Division 1 location is a location (a) In which combustible dust is in the air under normal operating conditions in quantities sufficient to produce explosive or ignitible mixtures, or (b) Where mechanical failure or abnormal operation of machinery or equipment might cause such explosive or ignitible mixtures to be produced, and might also provide a source of ignition through simultaneous failure of electric equipment, operation of protection devices, or from other causes, or (c) In which combustible dusts of an electrically conductive nature may be present in hazardous quantities. FPN: Combustible dusts that are electrically nonconductive include dusts produced in the handling and processing of grain and grain products, pulverized sugar and cocoa, dried egg and milk powders, pulverized spices, starch and pastes, potato and wood-flour, oil meal from beans and seed, dried hay, and other organic materials that may produce combustible dusts when processed or handled. Only Group E dusts are considered to be electrically conductive for classification purposes. Dusts containing magnesium or aluminum are particularly hazardous, and the use of extreme precaution will be necessary to avoid ignition and explosion.

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(2) Class II, Division 2. A Class II, Division 2 location is a location (a) Where combustible dust is not normally in the air in quantities sufficient to produce explosive or ignitible mixtures, and dust accumulations are normally insufficient to interfere with the normal operation of electrical equipment or other apparatus, but combustible dust may be in suspension in the air as a result of infrequent malfunctioning of handling or processing equipment and (b) Where combustible dust accumulations on, in, or in the vicinity of the electrical equipment may be sufficient to interfere with the safe dissipation of heat from electrical equipment or may be ignitible by abnormal operation or failure of electrical equipment. FPN No. 1: The quantity of combustible dust that may be present and the adequacy of dust removal systems are factors that merit consideration in determining the classification and may result in an nonhazardous area. FPN No. 2: Where products such as seed are handled in a manner that produces low quantities of dust, the amount of dust deposited may not warrant classification. (d) Class III Locations. Class III locations are those that are hazardous because of the presence of easily ignitible fibers or flyings, but in which such fibers or flyings are not likely to be in suspension in the air in quantities sufficient to produce ignitible mixtures. Class III locations shall include those specified in (a) and (b). (1) Class III, Division 1. A Class III, Division 1 location is a location in which easily ignitible fibers or materials producing combustible flyings are handled, manufactured, or used. FPN No. 1: Such locations usually include some parts of rayon, cotton, and other textile mills; combustible fiber manufacturing and processing plants; cotton gins and cotton-seed mills; flax-processing plants; clothing manufacturing plants; woodworking plants; and establishments and industries involving similar hazardous processes or conditions. FPN No. 2: Easily ignitible fibers and flyings include rayon, cotton (including cotton linters and cotton waste), sisal or henequen, istle, jute, hemp, tow, cocoa fiber, oakum, baled waste kapok, Spanish moss, excelsior, and other materials of similar nature. (2) Class III, Division 2. A Class III, Division 2 location is a location in which easily ignitible fibers are stored or handled other than in the process of manufacture. 500-5 Material Groups. For purposes of testing, approval, and area classification, various air mixtures (not oxygen-enriched) shall be grouped in accordance with Sections 500-5(a) and 500-5(b). Exception: Equipment approved for a specific gas, vapor, or dust. FPN: This grouping is based on the characteristics of the materials. Facilities are available for testing and identifying equipment for use in the various atmospheric groups. (a) Class I Group Classifications . Class I groups shall be as follows. (1) Group A. Acetylene. (2) Group B. Flammable gas, flammable liquid­produced vapor, or combustible liquid­produced vapor mixed with air that may burn or explode, having either a maximum experimental safe gap (MESG) value less than or equal to 0.45 mm or a minimum igniting current ratio (MIC ratio) less than or equal to 0.40. FPN: A typical Class I, Group B material is hydrogen.

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(MESG) value greater than 0.45 mm and less than or equal to 0.75 mm, or a minimum igniting current ratio (MIC ratio) greater than 0.40 and less than or equal to 0.80. FPN: A typical Class I, Group C material is ethylene.

(4) Group D. Flammable gas, flammable liquid­produced vapor, or combustible liquid­produced vapor mixed with air that may burn or explode, having either a maximum experimental safe gap (MESG) value greater than 0.75 mm or a minimum igniting current ratio (MIC ratio) greater than 0.80. FPN: A typical Class I, Group D material is propane. Exception: For atmospheres containing ammonia, the authority having jurisdiction for enforcement of this Code shall be permitted to reclassify th location to a less hazardous location or a nonhazardous location. FPN No. 1: For additional information on the properties and group classification of Class I materials, see Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 497-1997, and Guide to Fire Hazard Properties of Flammable Liquids, Gases, and Volatile Solids, NFPA 325-1994. FPN No. 2: The explosion characteristics of air mixtures of gases or vapors vary with the specific material involved. For Class I locations, Groups A, B, C, and D, the classification involves determinations of maximum explosion pressure and maximum safe clearance between parts of a clamped joint in an enclosure. It is necessary, therefore, that equipment be approved not only for class but also for the specific group of the gas or vapor that will be present. FPN No. 3: Certain chemical atmospheres may have characteristics that require safeguards beyond those required for any of the above groups. Carbon disulfide is one of these chemicals because of its low ignition temperature [100ºC (212ºF)] and the small joint clearance permitted to arrest its flame. FPN No. 4: For classification of areas involving ammonia atmosphere, see Safety Code for Mechanical Refrigeration, ANSI/ASHRAE 15-1994, and Safety Requirements for the Storage and Handling of Anhydrous Ammonia, ANSI/CGA G2.1-1989. (b) Class II Group Classifications. Class II groups shall be as follows. (1) Group E. Atmospheres containing combustible metal dusts, including aluminum, magnesium, and their commercial alloys, or other combustible dusts whose particle size, abrasiveness, and conductivity present similar hazards in the use of electrical equipment. FPN: Certain metal dusts may have characteristics that require safeguards beyond those required for atmospheres containing the dusts of aluminum, magnesium, and their commercial alloys. For example, zirconium, thorium, and uranium dusts have extremely low ignition temperatures [as low as 20ºC (68ºF)] and minimum ignition energies lower than any material classified in any of the Class I or Class II Groups. (2) Group F. Atmospheres containing combustible carbonaceous dusts that have more than 8 percent total entrapped volatiles (see Standard Test Method for Volatile Material in the Analysis Sample for Coal and Coke, ASTM D3175-89, for coal and coke dusts) or that have been sensitized by other materials so that they present an explosion hazard. Coal, carbon black, charcoal, and coke dusts are examples of carbonaceous dusts.

Exception No. 1: Group D equipment shall be permitted to be used for (3) Group G. Atmospheres containing combustible dusts not atmospheres containing butadiene provided all conduit runs into included in Group E or F, including flour, grain, wood, plastic, explosionproof equipment are provided with explosionproof seals installed chemicals. and within 18 in. (457 mm) of the enclosure. FPN No. 1: For additional information on group Exception No. 2: Group C equipment shall be permitted to be used for classification of Class II materials, see Recommended atmospheres containing allyl glycidyl ether, n-butyl glycidyl ether, Practice for the Classification of Combustible Dusts and ethylene oxide, propylene oxide, and acrolein provided all conduit runs of Hazardous (Classified) Locations for Electrical into explosionproof equipment are provided with explosionproof seals Installations in Chemical Process Areas, NFPA 499-1997. installed within 18 in. (457 mm) of the enclosure. FPN No. 2: The explosion characteristics of air mixtures of dust vary with the materials involved. For Class II (3) Group C. Flammable gas, flammable liquid­produced vapor, locations, Groups E, F, and G, the classification involves or combustible liquid­produced vapor mixed with air that may the tightness of the joints of assembly and shaft openings burn or explode, having either a maximum experimental safe gap

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to prevent the entrance of dust in the dust-ignitionproof enclosure, the blanketing effect of layers of dust on the equipment that may cause overheating, and the ignition temperature of the dust. It is necessary, therefore, that equipment be approved not only for the class, but also for the specific group of dust that will be present. FPN No. 3: Certain dusts may require additional precautions due to chemical phenomena that can result in the generation of ignitible gases. See National Electrical Safety Code, ANSI C2-1997, Section 127A, Coal Handling Areas. 500 -6 Protection Techniques. The following shall be acceptable protection techniques for electrical and electronic equipment in hazardous (classified) locations. (a) Explosionproof Apparatus. This protection technique shall be permitted for equipment in those Class I, Division 1 and 2 locations for which it is approved. FPN: Explosionproof apparatus is defined in Article 100. For further information, see Explosionproof and DustIgnitionproof Electrical Equipment for Use in Hazardous (Classified) Locations, ANSI/UL 1203-1994. (b) Dust Ignitionproof. This protection technique shall be permitted for equipment in those Class II, Division 1 and 2 locations for which it is approved. FPN: Dust-ignitionproof equipment is defined in Article 100. For further information, see Explosionproof and Dust-Ignitionproof Electrical Equipment for Use in Hazardous (Classified) Locations, ANSI/UL 1203-1994. (c) Dusttight. This protection technique shall be permitted for equipment in those Class II, Division 2 and Class III locations for which it is approved. FPN No. 1: Dusttight enclosures are constructed so that dust will not enter the enclosing cases under specified test conditions. FPN No. 2: For further information, see Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1 and 2 Hazardous (Classified) Locations, ANSI/ISA S12.12-1994, and Electrical Equipment for Use in Class I and II, Division 2 and Class III Hazardous (Classified) Locations, UL 1604-1994. FPN No. 3: For further information on test conditions for equipment other than rotating equipment, see Enclosures for Electrical Equipment (1000 volts Maximum), ANSI/NEMA 250-1991. (d) Purged and Pressurized. This protection technique shall be permitted for equipment in any hazardous (classified) location for which it is approved. FPN No. 1: In some cases, hazards may be reduced or hazardous (classified) locations limited or eliminated by adequate positive-pressure ventilation from a source of clean air in conjunction with effective safeguards against ventilation failure. FPN No. 2: For further information, see Standard for Purged and Pressurized Enclosures for Electrical Equipment, NFPA 496-1998. (e) Intrinsically Safe Systems. Intrinsically safe apparatus and wiring shall be permitted in any hazardous (classified) location for which it is approved, and the provisions of Articles 501 through 503 and 510 through 516 shall not be considered applicable to such installations, except as required by Article 504. Installation of intrinsically safe apparatus and wiring shall be in accordance with the requirements of Article 504. FPN: For further information, see Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I, II, and III, Division 1, Hazardous Locations, ANSI/UL 913-1997. (f) Nonincendive. A protective technique where, under normal operating conditions, any arcing or thermal effects are not capable of igniting the flammable gas, vapor, or dust-in-air mixture. This protection technique shall be permitted for equipment in those Class I, Division 2; Class II, Division 2; and Class III locations for which it is approved. (1) Nonincendive Circuit. A circuit in which any arc or thermal effect produced, under intended operating conditions of the equipment or due to opening, shorting, or grounding of field wiring, is not capable, under specified test conditions, of igniting the flammable gas­, vapor­, or dust­air mixture. FPN No. 1: For test conditions, see Nonincendive Electrical Equipment for Use in Class I and II, Division

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2, and Class III, Division 1 and 2 Hazardous (Classified) Locations, ANSI/ISA S12.12-1994. FPN No. 2: Nonincendive circuit is defined in Article 100. For further information, see Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Division 1 and 2 Hazardous (Classified) Locations, ANSI/ISA S12.12-1994. (2) Nonincendive Equipment. Equipment having electrical/electronic circuitry that is incapable, under normal operating conditions, of causing ignition of a specified flammable gas­, vapor­, or dust­air mixture due to arcing or thermal means. FPN: For further information, see Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1 and 2 Hazardous (Classified) Locations, ANSI/ISA-S12.12-1994. (3) Nonincendive Component A component having contacts for . making or breaking an incendive circuit and the contacting mechanism shall be constructed so that the component is incapable of igniting the specified flammable gas­ or vapor­air mixture. The housing of a nonincendive component is not intended to exclude the flammable atmosphere or contain an explosion. This protection technique shall be permitted for currentinterrupting contacts in those Class I, Division 2 locations for which the component is approved. FPN: For further information, see Electrical Equipment for Use in Class I and II, Division 2, and Class III Hazardous (Classified) Locations, UL 1604-1994. (g) Oil Immersion. This protection technique shall be permitted for current-interrupting contacts in Class I, Division 2 locations as described in Section 501-6(b)(1)(b). FPN: See Sections 501-3(b)(1), Exception (a); 5015(a)(1), Exception (b), 501-6(b)(1); 501-14(b)(1), Exception (a); 502-14(a)(2), Exception; and 50214(a)(3), Exception. For further information, see Industrial Control Equipment for Use in Hazardous (Classified) Locations, ANSI/UL 698-1995. (h) Hermetically Sealed. A hermetically sealed device shall be sealed against the entrance of an external atmosphere and the seal shall be made by fusion, e.g., soldering, brazing, welding, or the fusion of glass to metal. This protection technique shall be permitted for currentinterrupting contacts in Class I, Division 2 locations. FPN: See Sections 501-3(b)(1), Exception (b); 5015(a)(1), Exception (a); 501-6(b)(1)(a); and 50114(b)(1), Exception (b). For further information, see Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Division 1 and 2 Hazardous (Classified) Locations, ANSI/ISA S12.121994. (i) Other Protection Techniques. Other protection techniques used in equipment listed for use in hazardous (classified) locations. 500 -7 Equipment. Articles 500 through 504 require equipment construction and installation that will ensure safe performance under conditions of proper use and maintenance. FPN No. 1: It is important that inspection authorities and users exercise more than ordinary care with regard to installation and maintenance. FPN No. 2: Low ambient conditions require special consideration. Explosionproof or dust-ignitionproof equipment may not be suitable for use at temperatures lower than -25ºC (-13ºF) unless they are identified for low-temperature service. However, at low ambient temperatures, flammable concentrations of vapors may not exist in a location classified Class I, Division 1 at normal ambient temperature. (a) Approval for Class and Properties. (1) Equipment shall be approved not only for the class of location but also for the explosive, combustible, or ignitible properties of the specific gas, vapor, dust, fiber, or flyings that will be present. In addition, Class I equipment shall not have any exposed surface that operates at a temperature in excess of the ignition temperature of the specific gas or vapor. Class II equipment shall not have an external temperature higher than that specified in Section 500-7(2). Class III equipment shall not exceed the maximum surface temperatures specified in Section 503-1. (2) Equipment that has been approved for a Division 1 location shall be permitted in a Division 2 location of the same class and group.

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(3) Where specifically permitted in Articles 501 through 503, general-purpose equipment or equipment in general-purpose enclosures shall be permitted to be installed in Division 2 locations if the equipment does not constitute a source of ignition under normal operating conditions. (4) Equipment, regardless of the classification of the location in which it is installed, that depends on a single compression seal, diaphragm, or tube to prevent flammable or combustible fluids from entering the equipment, shall be approved for a Class I, Division 2 location. Exception: Equipment installed in a Class I, Division 1 location shall be suitable for the Division 1 location. FPN: See Section 501-5(f)(3) for additional requirements. (5) Unless otherwise specified, normal operating conditions for motors shall be assumed to be rated full-load steady conditions. (6) Where flammable gases or combustible dusts are or may be present at the same time, the simultaneous presence of both shall be considered when determining the safe operating temperature of the electrical equipment. FPN: The characteristics of various atmospheric mixtures of gases, vapors, and dusts depend on the specific material involved.

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Table 500-7(b). Identification Numbers Maximum Temperature Identification ºC ºF Number 450 842 T1 300 572 T2 280 536 T2A 260 500 T2B 230 446 T2C 215 419 T2D 200 392 T3 180 356 T3A 165 329 T3B 135 275 T4 120 248 T4A 100 212 T5 85 185 T6

(b) Marking. Approved equipment shall be marked to show the (c) Temperature. class, group, and operating temperature or temperature range (1) Class I Temperature. The temperature marking specified in (b) referenced to a 40ºC ambient. shall not exceed the ignition temperature of the specific gas or Exception No. 1: Equipment of the non-heat-producing type, such as vapor to be encountered. junction boxes, conduit, and fittings, and equipment of the heatFPN: For information regarding ignition temperatures of producing type having a maximum temperature not more than 100ºC gases and vapors, see Recommended Practice for the (212ºF) shall not be required to have a marked operating temperature or Classification of Combustible Dusts and of Hazardous temperature range. (Classified) Locations for Electrical Installations in Exception No. 2: Fixed lighting fixtures marked for use in Class I, Chemical Process Areas, NFPA 499-1997, and Guide to Division 2 or Class II, Division 2 locations only shall not be required to Fire Hazard Properties of Flammable Liquids, Gases, be marked to indicate the group. and Volatile Solids, NFPA 325-1994. Exception No. 3: Fixed general-purpose equipment in Class I locations, other than fixed lighting fixtures, that is acceptable for use in Class I, (2) Class II Temperature. The temperature marking specified in Division 2 locations shall not be required to be marked with the class, (b) shall be less than the ignition temperature of the specific dust group, division, or operating temperature. to be encountered. For organic dusts that may dehydrate or Exception No. 4: Fixed dusttight equipment other than fixed lighting carbonize, the temperature marking shall not exceed the lower of fixtures that are acceptable for use in Class II, Division 2 and Class III either the ignition temperature or 165ºC (329ºF). locations shall not be required to be marked with the class, group, FPN: See Recommended Practice for the Classification of division, or operating temperature. Combustible Dusts and of Hazardous (Classified) Exception No. 5: Electric equipment suitable for ambient temperatures Locations for Electrical Installations in Chemical Process exceeding 40ºC (104ºF) shall be marked with both the maximum ambient Areas, NFPA 499-1997, for minimum ignition temperature and the operating temperature or temperature range at that temperatures of specific dusts. ambient temperature. The ignition temperature for which equipment was approved prior FPN: Equipment not marked to indicate a division, or to this requirement shall be assumed to be as shown in Table 500marked "Division 1" or "Div. 1," is suitable for both 7(2) below. Division 1 and 2 locations. Equipment marked "Division 2" or "Div. 2" is suitable for Division 2 locations only. The temperature range, if provided, shall be indicated in identification numbers, as shown in Table 500-7(b). Identification numbers marked on equipment nameplates shall be in accordance with Table 500-7(b). Equipment that is approved for Class I and Class II shall be marked with the maximum safe operating temperature, as determined by simultaneous exposure to the combinations of Class I and Class II conditions. FPN: Since there is no consistent relationship between explosion properties and ignition temperature, the two are independent requirements. Table 500-7(2) Equipment that Is Not Subject to Overloading °C °F 200 392 200 392 165 329 Equipment (Such as Motors or Power Transformers) that May Be Overloaded Normal Abnormal Operation Operation °F °C °F 392 200 392 302 200 392 248 165 329

Class II Group E F G

°C 200 150 120

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( d) Threaded Conduit. All threaded conduit referred to herein shall be threaded with an NPT standard conduit cutting die that provides 3/4-in. taper per foot. Such conduit shall be made wrenchtight to prevent sparking when fault current flows through the conduit system, and ensure the explosionproof or dustignitionproof integrity of the conduit system where applicable. For equipment provided with metric threaded entries, such entries shall be identified as being metric, or listed adapters to permit connection to conduit or NPT-threaded fittings shall be provided with the equipment. Adapters shall be used for connection to conduit or NPT-threaded fittings. Listed cable fittings that have metric threads shall be permitted to be used. FPN: Threading specifications for metric threaded entries are located in Metric Screw Threads, ISO 965/1:1980 and Metric Screw Threads, ISO 965/3:1980. (e) Fiber Optic Cable Assembly. Where a fiber optic cable assembly contains conductors that are capable of carrying current, the fiber optic cable assembly shall be installed in accordance with the requirements of Articles 500, 501, 502, or 503, as applicable. 500-8. Specific Occupancies. Articles 510 through 517 cover garages, aircraft hangars, gasoline dispensing and service stations, bulk storage plants, spray application, dipping and coating processes, and health care facilities. SUBSTANTIATION: Currently, the introduction to Hazardous (Classified) Locations is presented with little regard to clarity and understanding. The text jumps from "classifications" to documentation to threaded conduit, to protection techniques, without ever providing groundwork as to the need for the protection techniques. Under the proposed revision, the reader is moved in a logical sequence, that defines general needs, addresses the classifications of locations, discusses material groups, before ever mentioning equipment. Then with protection techniques, equipment, equipment approvals, equipment markings and equipment designs are addressed. This provides a flow into the more specific sections beyond Article 500. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________

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AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #CP1405) 14- 4a - (500-2 and 505-2): Accept Note: The Technical Correlating Committee directs that this Proposal be reconsidered and directs the Code-Making Panel to use the definition currently in Article 100. The Technical Correlating Committee further directs that this Proposal be referred to Code-Making Panel 1 for action relative to the elimination of the existing Fine Print Note in the definition of "Identified" because the Fine Print Note contains permissive language and is not permitted by the NEC Style Manual. This action will be considered by Code-Making Panels 1 and 14 as a Public Comment. SUBMITTER: CMP 14 RECOMMENDATION: Add the following definition to 500-2 and 505-2: "Identified (as applied to equipment). Recognizable as suitable for the specific purpose, function, use, environment, application, etc., where prescribed in a particular Code requirement. FPN: Suitability of equipment for a specific purpose, environment, or application may be determined by: 1. equipment listing or labeling; 2. evidence of equipment evaluation from a qualified testing laboratory or inspection agency concerned with product evaluation; or 3.other evidence acceptable to the authority having jurisdiction such as a manufacturer's self evaluation or an owner's engineering judgement. (See definitions of Labeled and Listed)" SUBSTANTIATION: This definition clarifies the intent for approval of equipment. PANEL ACTION: Accept. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban COMMENT ON AFFIRMATIVE: BRIESCH: The Panel Action to include this definition in the special situations presented by hazardous locations is supported. However, it should be noted that it would be inappropriate to apply it generally to all chapters of the Code. JAGUNICH: See ballot for David Wechsler. WECHSLER: This was just one of the many Cook/Cox "identified, approved, listed, other" proposals in which the committee acted to develop a new definition for "identified" with a new fine print note (FPN) in Articles 500 and 505. This action was incorporated into the panel action rewrites for Articles 500 and 505, as noted in CP1401 and CP1402. ___________________ (Log #2264) 14- 5 - (500-2 (New) ): Reject SUBMITTER: David Wechsler, Union Carbide Corp. RECOMMENDATION: Add the following new second paragraph: Portable electrical or electronic devices or equipment shall not be required to comply with Chapter 5. SUBSTANTIATION: "500-1 Scope" indicates that "Articles 500 through 504 cover the requirements for electrical and electronic equipment and wiring for all voltages in Class I, Divisions 1 and 2..." The term "equipment" is defined in Article 100 as "A general term including material, fittings, devices, appliances, fixtures, apparatus, and the like used as a part of, or in connection with, an electrical installation." "Installation" is not an NEC defined term, but has as its meaning the concept of setting in place and being connected. As such, portable devices or equipment which are not part of an electrical installation are not addressed within Chapter 5 of the NEC and thus there are no requirements that such devices must comply with Chapter 5 of the NEC. PANEL ACTION: Reject. PANEL STATEMENT: This proposal conflicts with the action on Proposal 14-2a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________

Log #1545) 14- 4 - (500-1-Hazardous Classified Locations): Reject SUBMITTER: Thomas J. Conlan, Conlan's "The Electrician Inc." RECOMMENDATION: For simplicity add definitions to the nomenclature for Hazardous Classified Locations as H = Hazardous Classified, the next number if the Class and next number is the Division. H11 = Class 1 Division 1 H12 = Class 1 Division 2 H21 = Class 2 Division 1 H22 = Class 2 Division 2 H31 = Class 3 Division 1 H32 = Class 3 Division 2 Addresses using short version of the "H" system provides clarity as to exactly where the discussion is and where the location is. SUBSTANTIATION: This will simplify the practical applications to all H locations specifically among many others. For example 502-7(3) resistors and resistance devices shall have dustignitionproof enclosures approved for Class II locations. (Class II locations is specifically addressed to Section (a) Division I which requires one to look back to see where they were and this can cause confusion) So now the section would read: For example 502-7(3) Resistors and resistance devices shall have dust-ignitionproof enclosures approved for H21 locations. [Where H21 means Hazardous/Class 2/ Division 1 real simple and easy to understand immediately] PANEL ACTION: Reject. PANEL STATEMENT: The technical substantiation does not support the use of arabic numerals for the Class designation. Thus, the use of arabic numerals would be contrary to the NEC style manual. Additionally, there is no substantiation that a problem exists. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION:

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(Log #2263) 14- 6 - (500-2-Electrical and Electronic Equipment): Accept in Principle SUBMITTER: David Wechsler, Union Carbide Corp. RECOMMENDATION: Add the following new section "Definitions" and renumber all existing paragraphs/sections accordingly: Definitions. The following definition applies for Chapter 5: Electrical and Electronic Equipment ­ Includes material, fittings, devices, appliances, fixtures, apparatus, and the like that is part of, or in connection with, an electrical installation, as well as any portable or transportable device having a battery or other electrical power source. SUBSTANTIATION: It may be inferred that because "500-1 Scope" indicates that "Articles 500 through 504 cover the requirements for electrical and electronic equipment and wiring for all voltages in Class I, Divisions 1 and 2..." and the term "equipment" as defined in Article 100 applies only to installed electrical/electronic devices, appliances, fixtures, apparatus, etc. that portable electrical devices are excluded from the requirements of Chapter 5. With this new definition, this ambiguity is removed and portable electrical devices are required to comply with Chapter 5. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 9 NEGATIVE: 3 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: GOODMAN: Although I agree with the intent that all equipment including "portable or transportable devices having a battery or other electrical power source" should be properly rated for the location in which it will be used, there is a practical element that makes this unenforceable and unrealistic. First, without an actual "installation", there is some question as to whether this is within the scope of the NEC at all. Secondly, there are classified areas in public places, such as at gasoline dispensers, where this code provision as written would apply, but is totally unenforceable. For example, I would be in violation of the NEC whenever I pump gas because my battery powered watch is not approved (or identified) for the classified areas. Within operating plants and other company facilities that do not have public access, safety rules banning the use of nonapproved equipment in classifed areas or specifying the necessary permitting and safety requirements to ensure their safe operation are typical throughout the affected industries. Adding all these battery powered equipment items, without exception, is unrealistic and does not add anything substantial to the NEC which is an installation-based document. OMEARA: The proposal needs to be rejected because the definition is too broad. ZIPSE: I agree with Mr. Goodman's Explanation of Negative Vote. ___________________ (Log #2309) 14- 7 - (500-3(a)): Reject SUBMITTER: Sukanta Sengupta, FMC Corp. RECOMMENDATION: Revise the last line of the first paragraph as follows. "Locations with Oxygen enriched atmospheres or locations where pyrophoric materials are the only materials used or handled shall not be classified." SUBSTANTIATION: This statement will be compatible to NFPA 497 paragraph 1-1.5 which includes "Oxygen enriched atmosphere" in defining areas not to be classified. PANEL ACTION: Reject. PANEL STATEMENT: Locations where oxygen is the only material present are already excluded by 500-1. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________

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(Log #2146) 14- 8 - (500-3(a), FPN (New) ): Accept in Principle SUBMITTER: Kari Barrett, Chemical Manufacturers Assn. RECOMMENDATION: Replace "nonhazardous" with "unclassified". SUBSTANTIATION: This is a companion to other proposals which provide a definition of unclassified in Articles 100, 500, and 505, and provides correlation. The term "Classified" refers to the type of material/hazard potential involved, i.e., Class I, Division 1, Class II, Division 2, etc. Terms such as nonhazardous and unclassified are used in both the NEC, the Uniform Building Code (UBC) and other NFPA documents. The term nonhazardous infers that the area has "no" hazards while the term "unclassified" more clearly correlates with the condition of being reviewed but found not to need classification. This action provides needed correlation with other NFPA documents, such as NFPA 497. Additionally the term "nonhazardous" is used 7 times within various parts of the NEC and in at least one place in the NEC the meaning of nonhazardous applies to voltages and not classification. A companion proposal has been made to change the term "nonhazardous" to "unclassified" as appropriate elsewhere in the NEC. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #2384) 14- 9 - (500-3(b)): Reject SUBMITTER: William E. Bickner, Stillwater, MN RECOMMENDATION: Revise Section 500-3(b) as shown below: 500-3(b). Documentation. All areas designated as hazardous (classified) locations shall be properly documented. Where, in the judgement of the authority having jurisdiction, flammable gases or vapors, volatile flammable liquids, combustible dust, or ignitable fibers or flyings are or may be present in potentially hazardous quantity or concentration in any indoor or outdoor location, upon written request of the authority having jurisdiction, a person responsible for the installation of wiring or equipment in such location shall provide documentation, prepared by or under the supervision of a qualified person acceptable to the authority having jurisdiction, which delineates the extent, class, division or zone, and group, of any classified locations, or certifies the absence thereof. Where a classification depends on factors such as mechanical ventilation, atmospheric pressure differentials, or determination of lower flammable limit percentages, the relevant data shall be included in the documentation. This documentation shall be available to those authorized to design, install, inspect, maintain or operate electrical equipment at the location. SUBSTANTIATION: This section fails to state what must be documented. The present requirement is too vague to be enforceable and becomes onerous if broadly interpreted and applied to all potentially hazardous locations. However, it would be generally useful with the changes proposed, which empower the authority having jurisdiction to require documentation where appropriate, but forgo it where not needed. For example, Articles 511 to 517 generally define classified areas in the covered occupancies, but such documentation would be useful for other types of occupancies, or where the extent of a classified area is undefined or uncertain or it is proposed to reduce or eliminate a classification by suitable means. PANEL ACTION: Reject. PANEL STATEMENT: Area classification criteria is covered in other sections of the code. The existing text is adequate. Format and requirements for documentation may vary from authority having jurisdiction to authority having jurisdiction and other compliance requirements, such as process safety management, may apply. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________

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(Log #1258) 14- 10 - (500-3(d) and 500-5(a)(2)): Reject Note: It was the action of the Technical Correlating Committee that this Proposal be reconsidered by the Panel. The issues of raceway trade size, extracts, and use of soft versus hard metrication were all studied in detail and resolutions were communicated to the Panel prior to the Panel Meeting. It should be noted that all of the other Code-Making Panels accepted the metrication directive. This action will be considered by the Panel as a Public Comment. SUBMITTER: Technical Correlating Committee National Electrical Code RECOMMENDATION: In 500-3(d), change the first sentence to read: "All threaded conduit referred to herein shall be threaded with an NPT standard cutting die that provides 3/4 in. a taper of 1 in 16 per foot." In 500-5(a)(2) Exception No. 1 and Exception No. 2, in both exceptions, change "18 in. (457 mm)" to "450 mm (18 in.)" SUBSTANTIATION: The proposed revision complies with the NFPA 1M Manual of Style Section 4-1 with respect to the placement of units, i.e., to show the SI units as the preferred unit and the inch-pound units immediately following in parenthesis. PANEL ACTION: Reject. PANEL STATEMENT: CMP 14 believes the following issues need further evaluation before changes are made to the code: trade sizes of conduit; extract policies; consistency from article to article within the code. For example, trade size of conduit is not a true dimension and cannot be converted to a true metric number. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 9 NEGATIVE: 3 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: KUCZKA: Panel Action should have been Accept in Principle. Metric conversion should be exact rather than rounded. OMERA: The proposal should be accepted to be in conformance with Chapter 4 of the NFPA MOS-1 Manual of Style. ZIPSE: The Institute of Electrical and Electronics Engineers, Inc. policy is SI units are to be used. ___________________ (Log #2842) 14- 11 - (500-3(d)): Accept in Principle Note: It was the action of the Technical Correlating Committee that the Panel Statement be modified to also refer to 500-8(d) of the rewrite of Article 500 in Proposal 14-2a. SUBMITTER: Melvin K. Sanders, Ankeny, IA RECOMMENDATION: Provide the name for the "NPT" acronym so it would read when first encountered, remaining text as in the 1999 Edition: (d) Threaded Conduit. All threaded conduit referred to herein shall be threaded with a National Pipe Thread ( NPT ) standard conduit cutting die that provides 3/4-in. taper per foot. Such conduit shall be made wrenchtight to prevent sparking when fault current flows through the conduit system, and ensure the explosionproof or dust-ignitionproof integrity of the conduit system where applicable. For equipment provided with metric threaded entries, such entries shall be identified as being metric, or listed adapters to permit connection to conduit or NPT-threaded fittings shall be provided with the equipment. Adapters shall be used for connection to conduit or NPT-threaded fittings. Listed cable fittings that have metric threads shall be permitted to be used. FPN: Threading specifications for metric threaded entries are located in Metric Screw Threads, ISO 965/1:1980 and Metric Screw Threads, ISO 965/3:1980. SUBSTANTIATION: Standard practice is to not use an acronym unless accompanied the first time by the full name to avoid confusion that the pipe thread in question is for a conduit thread taper per foot and not a plumbing thread taper per foot to ensure the five full threads required by Section 501-4(a) are fully engaged. PANEL ACTION: Accept in Principle.

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PANEL STATEMENT: The panel agrees with the submitter, but has used the correct term, as taken from ANSI/ASME B1.20.1. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3234) 14- 12 - (500-3(d) and (e)): Reject SUBMITTER: Sukanta Sengupta, FMC Corp. RECOMMENDATION: Move these two sections to Article 501, Article 502 and Article 503. SUBSTANTIATION: Editorial change. Application related topics like these should not be mixed up with general topics. PANEL ACTION: Reject. PANEL STATEMENT: These are general requirements that belong in the "General" section of the chapter. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1546) 14- 13 - (500-4(a)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (a) Explosionproof Apparatus. This protection technique shall be permitted for equipment in those Class I, Division 1 and 2 locations for which it is approved. (identified.) . SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. GPANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: I am voting negative at this time on all the proposals to change "approved". I will change my vote at the comment stage if the acceptance of the definition found in Proposal 14-4a, Sections 500-2 and 505-2 is accepted by the Panel and the Technical Correlating Committee. If the definition is rejected by the Panel or the Technical Correlating Committee, then all proposals to change "approve" by Mr. Cook and Mr. Cox will remain rejected. COMMENT ON AFFIRMATIVE: LAWRENCE: The panel needs to review the use of "Approved," "Listed," and "Identified" throughout Articles 500 through 516 to confirm that the use of these terms correlates through all of the text and cross-references. As one example of a correlation problem, 505-8(b) uses "Approved" for the protection technique of purged and pressurized. 505-9(a) refers to equipment being "identified". The term in 505-8(b) should have been revised to "Identified" as part of the action to revise 505-9(a). WECHSLER: Clarification for Cook/Cox proposals - addressing "identified, approved, listed, other" -- all these proposals were acted upon based upon committee action to provide a new definition for "identified" with a new fine print note (FPN) in Articles 500 and 505. It was my understanding that all these proposals and not just those with the change to "identified" were to be contingent upon this definition of "identified" with its fine print note, as reflected in CP1405. Only those with the word identified appear to have the statement "Acceptance of this proposal is contingent upon acceptance of the fine print note to the definition of "Identified" in Proposal 14-4a (Log #CP1405). ___________________

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(Log #4482) 14- 14 - (500-4(a)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (a) Explosionproof Apparatus. This protection technique shall be permitted for equipment in those Class I, Division 1 and 2 locations for which it is approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1547) 14- 15 - (500-4(b)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (b) Dust Ignitionproof. This protection technique shall be permitted for equipment in those Class II, Division 1 and 2 locations for which it is approved. (identified.)) SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3456) 14- 16 - (500-4(b)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (b) Dust Ignitionproof. This protection technique shall be permitted for equipment in those Class II, Division 1 and 2 locations for which it is approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________

Copyright 2000, NFPA

(Log #3814) 14- 17 - (500-4(b), FPN): Accept in Principle SUBMITTER: Douglas Hansen, Codecheck RECOMMENDATION: Revise the FPN to read as follows: FPN: Dust-ignitionproof equipment is defined in Article 100 Section 502-1 . SUBSTANTIATION: There is no definition of dust-ignitionproof in Article 100. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1548) 14- 18 - (500-4(c)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (c) Dusttight. This protection technique shall be permitted for equipment in those Class II, Division 2 and Class III locations for which it is approved. (identified.) SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3457) 14- 19 - (500-4(c)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (c) Dusttight. This protection technique shall be permitted for equipment in those Class II, Division 2 and Class III locations for which it is approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1549) 14- 20 - (500-4(d)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (d) Purged and Pressurized. This protection technique shall be permitted for equipment in any hazardous (classified) location for which it is approved. (identified.)

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SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: This was just one of the many Cook/Cox "identified, approved, listed, other" proposals in which the committee acted to develop a new definition for "identified" with a new fine print note (FPN) in Articles 500 and 505. This action was incorporated into the panel action rewrites for Articles 500 and 505, as noted in CP1401 and CP1402. See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3458) 14- 21 - (500-4(d)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (d) Purged and Pressurized. This protection technique shall be permitted for equipment in any hazardous (classified) location for which it is approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1550) 14- 22 - (500-4(e)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (e) Intrinsically Safe Systems. Intrinsically safe apparatus and wiring shall be permitted in any hazardous (classified) locations for which it is approved (identified), and the provisions of Articles 501 through 503 and 510 through 516 shall not be considered applicable to such installations, except as required by Article 504. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban

Copyright 2000, NFPA

EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3334) 14- 23 - (500-4(e)): Reject SUBMITTER: Sukanta Sengupta, FMC Corp. RECOMMENDATION: Revise the first paragraph as follows: (e) Intrinsically Safe System. Intrinsically safe apparatus and wiring shall be permitted in any hazardous (classified) locations for which it is approved. SUBSTANTIATION: I. Let Article 504 be the only article for details. It addresses the integral parts of intrically safe system's wiring like associated apparatus wiring. II. Only Articles 501, 502, 503 and 505 are coverd in article 505 not 510 through 516 as shown in the first line. PANEL ACTION: Reject. PANEL STATEMENT: The submitter offers no substantiation to remove this provision as it is currently worded. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3459) 14- 24 - (500-4(e)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (e) Intrinsically Safe Systems. Intrinsically safe apparatus and wiring shall be permitted in any hazardous (classified) location for which it is approved (identified), and the provisions of Articles 501 through 503 and 510 through 516 shall not be considered applicable to such installations, except as required by Article 504. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1970) 14- 25 - (500-4(f)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise the first paragraph, second sentence to read as follows: This protection technique shall be permitted for equipment in those Class I, Division 2; Class II, Division 2; and Class III locations for which it is approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban

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EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3460) 14- 26 - (500-4(f)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise paragraph one, sentence two to read as follows: "This protection technique shall be permitted for equipment in those Class I, Division 2: Class II, Division 2: and Class III locations for which it is approved (identified)." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #4235) 14- 27 - (500-4(f)): Accept in Principle SUBMITTER: Frederic P. Hartwell, Hartwell Electrical Services, Inc./Rep. Massachusetts Electrical Code Advisory Committee RECOMMENDATION: Delete paragraph (1) and (1) (FPN No. 1). Redesignate (FPN No. 2) as (FPN), applying only to the initial paragraph of Section 500-4(f), and ahead of the subsequent paragraphs. Change "(2)" to "(1)" and "(2)a." to "(2)". SUBSTANTIATION: The 1999 NEC contains a direct conflict between the definition of "Nonincendive Circuit" as it appears in Article 100 and the version that appears in Section 500-4(f)(1). The version in Article 100 is correct, and technically threatened with noneffectiveness because the wrong definition appears in Chapter 5. This was the result of a panel error that this proposal corrects. The other changes are editorial and properly format a subsection that just lost one of its two subsections by promoting the two paragraphs in "a." to a number item "(2)". This can be done safely because although nonincendive components are part of equipment, both they and the equipment will stand as part of the general concept of nonincendive. In addition, the second paragraph of NEC "(2)a." adequately restrains its application to current-interrupting contacts, and the network of fine print notes that will remain refer to both the definition of "Nonincendive Circuit" in Article 100 and also to all the relevant product standards. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1551) 14- 28 - (500-4(f)(2)a): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise paragraph two to read as follows: This protection technique shall be permitted for currentinterrupting contacts in those Class I, Division 2 locations for which the component is approved (identified.) SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction

Copyright 2000, NFPA

would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3461) 14- 29 - (500-4(f)(2)(a)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: "This protection technique shall be permitted for currentinterrupting contacts in those Class I, Division 2 locations for which the component is approved (identified)." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1492) 14- 30 - (500-4(f)(3)-Associated Nonincendive Field Wiring Apparatus): Accept in Principle SUBMITTER: Nicholas Ludlam, Factory Mutual Research RECOMMENDATION: Associated Nonincendive Field Wiring Apparatus. Apparatus in which the circuits are not necessarily nonincendive themselves, but that affect the energy in the nonincendive field wiring circuits and are relied on to maintain nonincendive safety. Associated nonincendive field wiring apparatus may be either of the following: 1. Electrical apparatus that has an alternative-type protection for use in the appropriate hazardous (classified) location, or 2. Electrical apparatus not so protected that shall not be used within a hazardous (classified) location FPN No. 1: Associated nonincendive field wiring apparatus has identified associated nonincendive field wiring apparatus connections for nonincendive field wiring apparatus and also may have connections for other electrical apparatus. SUBSTANTIATION: The above definition would be required if the other proposed text on nonincendive field wiring is accepted. PANEL ACTION: Accept in Principle. Add the following definition to 500-2: "Associated Nonincendive Field Wiring Apparatus. Apparatus in which the circuits are not necessarily nonincendive themselves, but that affect the energy in the nonincendive field wiring circuits and are relied on to maintain nonincendive energy levels . Associated nonincendive field wiring apparatus may be either of the following: 1. Electrical apparatus that has an alternative-type protection for use in the appropriate hazardous (classified) location, or 2. Electrical apparatus not so protected that shall not be used within a hazardous (classified) location FPN: Associated nonincendive field wiring apparatus has designated associated nonincendive field wiring apparatus connections for nonincendive field wiring apparatus and also may have connections for other electrical apparatus."

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PANEL STATEMENT: The editorial changes shown as underlined text are for clarity. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1493) 14- 31 - (500-4(f)(4)-Nonincendive Field Wiring Apparatus): Accept in Principle SUBMITTER: Nicholas Ludlam, Factory Mutual Research RECOMMENDATION: Nonincendive Field Wiring Apparatus. A circuit in which any spark or thermal effect is incapable of causing ignition of a mixture of flammable or combustible material in air under prescribed normal operating conditions. FPN: Conditions are described in ISA S12.12.01:1994 Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1 and 2 Hazardous (Classified) Locations. SUBSTANTIATION: The above definition would be required if the other proposed text on nonincendive field wiring is accepted. PANEL ACTION: Accept in Principle. Add the following definition to 500-2: "Nonincendive Field Wiring Apparatus. Apparatus intended to be connected to nonincendive field wiring. FPN: Conditions are described in ISA S12.12:1994 Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1 and 2 Hazardous (Classified) Locations." PANEL STATEMENT: The definition has been reworded for clarity. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1490) 14- 32 - (500-4(j)-Ex Component): Reject SUBMITTER: Nicholas Ludlam, Factory Mutual Research RECOMMENDATION: Ex Component. Part of electrical apparatus for use in hazardous (classified) locations, which is not to be used alone in such locations and which requires additional evaluation of any electrical apparatus with which it is used. SUBSTANTIATION: This definition is based on the definition in ANSI/ISA S12.0.01-1998 (IEC 79-0 Mod) for an Ex component. Although this is not a type of protection in its own right, manufacturers could get components listed which would be marked with the appropriate information in 505-10. The definition is required to reinforce the proposed FPN to 505-10(b), and the proposed change to 505-10(3). The above definition is based on that of the ISA standard with `IEC' wording revised to align with that of the NEC. PANEL ACTION: Reject. PANEL STATEMENT: This is a product certification issue, not an installation issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1972) 14- 33 - (500-5, Exception): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise as follows: Exception: Equipment approved (identified) for a specific gas, vapor, or dust. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept.

Copyright 2000, NFPA

PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3462) 14- 34 - (500-5, Exception): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the Exception to read as follows: Exception: Equipment approved (identified) for a specific gas, vapor, or dust. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #2880) 14- 35 - (500-5(a)(1)): Reject SUBMITTER: Phillip Fields, Denver, CO RECOMMENDATION: Revise text to read as follows: Any liquid or gaseous material which is liquid under pressure and have a flash point below 73°F (22.8°C) and having a boiling point below 100°F (37.8°C) SUBSTANTIATION: Class 1 "A" is undefined. PANEL ACTION: Reject. PANEL STATEMENT: Group A is defined by NFPA 497 as acetylene. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #2038) 14- 36 - (500-5(a)(4)): Reject SUBMITTER: Mark O. Wise, Merritt Island, FL RECOMMENDATION: Revise text to read a follows: x(4) Group D. Flammable gas, flammable liquid-produced vapor, or combustible liquid-produced vapor liquid oxygen, mixed with air that may burn or explode, having either a maximum experimental safe gap (MESG) value greater than 0.75 mm or a minimum igniting current ratio (MIC ratio) greater than 0.80. SUBSTANTIATION: Add liquid oxygen as a Class 1, Group D commodity in order to comply with NFPA 30, and to enhance Article 500. PANEL ACTION: Reject. PANEL STATEMENT: Liquid oxygen is not a flammable material per NFPA 497. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________

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(Log #4418) 14- 37 - (500-5(a)(4)): Accept in Principle SUBMITTER: Jeffrey M. Shapiro, Int'l Code Consultants/Rep. Int'l Inst. of Ammonia Refrigeration RECOMMENDATION: Revise text to read as follows: 500.5(a)(4) Group D. Flammable gas, flammable liquidproduced vapor, or combustible liquid-produced vapor mixed with air that may burn or explode, having either a maximum experimental safe gap (MESG) value greater than 0.75 mm or a minimum igniting current ratio (MIC ratio) greater than 0.80. FPN: A typical Class I, Group D material is propane. Exception: Areas containing ammonia refrigeration equipment shall be permitted to be classified as nonhazardous locations when (1) continuous mechanical ventilation is provided and failure of the ventilation system actuates and alarm, or (2) vapor detection is provided to automatically activate a mechanical ventilation system and sound an alarm at a detection threshold of 1,000 parts-permillion or less. For atmospheres containing ammonia, the authority having jurisdiction for enforcement of this Code shall be permitted to reclassify the location to a less hazardous location or a nonhazardous location. FPN No. 1: For additional information on the properties and group classification of Class I materials, see NFPA 497, Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, 1997 edition and NFPA 325, Guide to Fire Hazard Properties of Flammable Liquids, Gases, and Volatile Solids, 1994 edition. FPN No. 2: The explosion characteristics of air mixtures of gases or vapors vary with the specific material involved. For Class I locations, Groups A, B, C, and D, the classification involves determinations of maximum explosion pressure and maximum safe clearance between parts of a clamped joint in an enclosure. It is necessary, therefore, that equipment be approved not only for class but also for the specific group of the gas or vapor that will be present. FPN No. 3: Certain chemical atmospheres may have characteristics that require safeguards beyond those required for any of the above groups. Carbon disulfide is one of these chemicals because of its low ignition temperature [100°C (212°F)] and the small joint clearance permitted to arrest its flame. FPN No. 4: For classification of areas involving ammonia atmosphere, see ANSI/ASHRAE 15-1994, Safety Code for Mechanical Refrigeration, and ANSI/CGA G2.1-1989, Safety Requirements for the Storage and Handling of Anhydrous Ammonia. SUBSTANTIATION: The purpose of this proposal is to clarify application of the code. The text of the existing exception unnecessarily complicates enforcement and introduces the opportunity for inconsistent application of the code for cases involving ammonia refrigeration systems. The intent of the exception, which is established through FPN No. 4, is to permit a reduction in the hazard classification for ammonia based on prescriptive allowance in ASHRAE 15. The referenced provisions in ASHRAE 15 are set forth in Sections 8.14(g) and (h) of that document, which provide the following: "(g) When refrigerants of Groups A2, A3, B2, and B3 are used, the machinery room shall conform to Class I, Division 2 of the National Electrical Code. When refrigerant Groups A1 and B1 are used, the machinery room is not required to meet Class I, Division 2 of the National Electrical Code. Exception: When ammonia is used, the requirements of Class I, Division 2 of the National Electrical Code shall not apply providing the requirements of 8.14(h) are met. (h) When ammonia is used, the machinery room is not required to meet Class I, Division 2 of the National Electrical Code providing (1) the mechanical ventilation system in the machinery room is run continuously and failure of the mechanical ventilation system actuates an alarm or (2) the machinery room is equipped with a vapor detector that will automatically start the mechanical ventilation system and actuate an alarm at a detection level not to exceed 1,000 ppm." Unlike many gases that support combustion [Lower Explosive Limit (LEL)] at concentrations of 10,000 to 20,000 parts per million (ppm), ammonia is not ignitable until the concentration reaches approximately 150,000 ppm. Because ammonia has a low propensity toward ignition, having such a high LEL, a narrow flammable range and a high required ignition energy, the U.S. Department of Transportation and other code writing organizations do not regulate ammonia as a "flammable gas" even though it can support combustion in limited circumstances. The existing exception for ammonia in Section 500.5(a)(4) has

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been regarded as necessary to clarify that areas containing ammonia refrigeration equipment should be classified as nonhazardous locations when controls specified in ASHRAE 15 are followed because of ammonia's unique properties. Since the technical aspects of ASHRAE 15's provisions related to classified locations are fairly short, it seems more appropriate to provide these regulations with NFPA 70 as opposed to forcing the code user to reference another standard (the proponent has contacted ASHRAE to acquire permission to include the conceptual information from ASHRAE 15 in the NEC based on this proposal). This will make the NEC easier to apply and more definitive in its application. PANEL ACTION: Accept in Principle. Add the following text to 500-3(a) after the Fine Print Note: "Rooms and areas containing ammonia refrigeration systems that are equipped with adequate mechanical ventilation, may be classified as "unclassified" locations. FPN: For further information regrading classification and ventilaton of areas involving ammonia, see Safety Code for Mechanical Refrigeration, ANSI/ASHRAE 15-1994, and Safety Requirements for the Storage and Handling of Anhydrous Ammonia, ANSI/CGA G2.1-1989 (14-37)" PANEL STATEMENT: The panel believes its proposed text more clearly meets the intent of the submitter. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1971) 14- 38 - (500-5(a)(4), FPN No. 2): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise the second sentence as follows: It is necessary, therefore, that equipment be approved (identified) not only for the class but also for the specific group of gas or vapor that will be present. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3463) 14- 39 - (500-5(a)(4), FPN No. 2): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the second sentence to read as follows: "It is necessary, therefore, that equipment be approved (identified) not only for class but also for the specific group of the gas or vapor that will be present." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a.

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NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #2132) 14- 40 - (500-5(a)(4), Exception): Accept in Principle SUBMITTER: Kari Barrett, Chemical Manufacturers Assn. RECOMMENDATION: Replace "nonhazardous" with "unclassified". SUBSTANTIATION: This is a companion to other proposals which provide a definition of unclassified in Articles 100, 500, and 505, and provides correlation. The term "Classified" refers to the type of material/hazard potential involved, i.e., Class I, Division 1, Class II, Division 2, etc. Terms such as nonhazardous and unclassified are used in both the NEC, the Uniform Building Code (UBC) and other NFPA documents. The term nonhazardous infers that the area has "no" hazards while the term "unclassified" more clearly correlates with the condition of being reviewed but found not to need classification. This action provides needed correlation with other NFPA documents, such as NFPA 497. Additionally the term "nonhazardous" is used 7 times within various parts of the NEC and in at least one place in the NEC the meaning of nonhazardous applies to voltages and not classification. A companion proposal has been made to change the term "nonhazardous" to "unclassified" as appropriate elsewhere in the NEC. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1195) 14- 41 - (500-5(b)(3) and FPN No. 4 (New) ): Reject Note: The Technical Correlating Committee directs that this Proposal be referred to the NFPA Committee on Electrical Equipment in Chemical Atmospheres for action. SUBMITTER: Terry L. Carlson, Nebraska State Electrical Board RECOMMENDATION: Revise 500-5(b)(3)text as follows: (3) Group G. Atmospheres containing combustible dusts not included in Group E or F, including flour, grain, plastic, chemicals, and fireworks explosives. Add new FPN as follows: FPN No. 4: Fireworks explosives includes but is not limited to dynamite, black powder, salute powder, pellet powder, initiating explosives, detonators, safety fuses, squibs, detonating cord, igniter cord, and igniters. The presence of fireworks explosives may require additional precautions due to the easy ignitability of the manufactured or stored product. See NFPA 1124, Code for the Manufacture, Transportation, and Storage of Fireworks. SUBSTANTIATION: Fireworks explosives are not presently covered by the NEC. Fireworks manufacturing, processing and storage facilities are very hazardous. A documented case that began in 1995 at Hastings, Nebraska is on record. A complete new wiring system was installed at a huge storage and processing facility. NEMA 1 type wiring was installed. A heat shrink wrap machine was installed for use in making small retail packages of fireworks. Because of the presence of the explosives, a Nebraska State Electrical Inspector red tagged the installation and wrote a Correction Order referencing NEC Article 502 to require the building to be rewired as a hazardous location along with removal of the heat shrink wrap machine. Attorneys for the building owner appealed the correction order, challenging the State Electrical Board. The attorneys reasoned that although NFPA 1124 does reference NEC Article 502 as a requirement, there is no specific wording in NEC Article 500 to 502 regarding fireworks explosives. After many months, NFPA responded to the board by stating a Formal Interpretation could not be given because the Code panel members could not come to agreement on whether or not the fireworks explosives are covered under the NEC articles. However, the Code panel did agree that NFPA 1124 is the Code that applies to fireworks explosives, that NFPA 1124 2-9 does reference NEC Article 502 as a wiring method for fireworks storage and processing buildings, and that Article 502 for some unknown reason does not

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reference fireworks explosives. Like thousands of governmental agencies, the Nebraska Legislature only adopts NFPA 70, the National Electrical Code, as State law to be used as the minimum standard for electrical wiring. Because there are no Code sections in the NEC to regulate fireworks explosives, the Nebraska State Electrical Board had no choice but to countermand the correction order and let the NEMA 1 type wiring remain in the building, along with the heat shrink wrap machine used for packaging the fireworks. Forty-two months later, on June 3, 1999, there was an explosion and fire in the facility while employees were making retail packages of fireworks. The explosion injured two employees, sending them to the hospital in critical condition with burns. Investigation showed that the open heating element on the heat shrink wrap machine ignited the fireworks explosives dust. Over the last few years there have been several explosions and fires in fireworks storage and processing facilities all over the United States. The stories have been reported on television and in newspapers. With this proposal, the National Electrical Code will address the problem by providing a standard for fireworks explosives wiring methods. This will help alleviate the chance of more people being killed or injured. PANEL ACTION: Reject. PANEL STATEMENT: Responsibility for group classification of dust is the responsibility of the T/C on Electrical Equipment in Chemical Atmospheres. 500-5(b)(3) is actually extracted text and should have been identified as such. This oversight will be editorially corrected. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1973) 14- 42 - (500-5(b)(3), FPN No. 2): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise the third sentence as follows: It is necessary, therefore, that equipment be approved (identified) not only for the class, but also for the specific dust that will be present. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3464) 14- 43 - (500-5(b)(3), FPN No. 2): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the third sentence to read as follows: "It is necessary, therefore, that equipment be approved (identified) not only for the class, but also for the specific group of dust that will be present." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept.

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PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1552) 14- 44 - (500-5(c)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (c) Approval for Class and Properties. Equipment, regardless of the classification of the location in which it is installed, that depends on a single compression seal, diaphragm, or tube to prevent flammable or combustible fluids from entering the equipment, shall be approved (identified) for a Class I, Division 2 location. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #1966) 14- 45 - (500-5(c)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise the fourth paragraph as follows: Equipment that has been approved (identified) for a Division1 location shall be permitted in a Division 2 location of the same class and group. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________

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(Log #1974) 14- 46 - (500-5(c)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise the third paragraph as follows: Equipment shall be approved (identified) not only for the class of location but also for the explosive, combustible, or ignitable properties of the specific gas, vapor, dust, fiber, or flyings that will be present. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3465) 14- 47 - (500-5(c)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: "Equipment that has been approved (identified) for a Division 1 location shall be permitted in a Division 2 location of the same class and group." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3466) 14- 48 - (500-5(c)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the third paragraph to read as follows: "Equipment shall be approved (identified) not only for the class of location but also for the explosive, combustible, or ignitable properties of the specific gas, vapor, dust, fiber, or flyings that will be present." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a.

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NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1965) 14- 49 - (500-5(d)): Accept in Principle in Part SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise the fourth paragraph as follows: Equipment that is approved (identified) for Class I and Class II shall be marked with the maximum safe operating temperature, as determined by simultaneous exposure to the combinations of Class I and Class II conditions. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle in Part. Delete the words "that is appproved". PANEL STATEMENT: Marking is already required. See also Proposal 14-2a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #2129) 14- 50 - (500-5(d)): Accept in Principle SUBMITTER: Kari Barrett, Chemical Manufacturers Assn. RECOMMENDATION: Change the wording of the first paragraph as follows: (d) Marking. Approved equipment shall be marked to show the class, group, and operating temperature or temperature classification range referenced to a 40°C ambient. The temperature classification, if provided, shall be indicated using the temperature identification (T Codes) shown in Table 500-5(d). Delete the following existing paragraphs: "The temperature range, if provided, shall be indicated in identification numbers, as shown in Table 500-5(d). Identification numbers marked on equipment nameplates shall be in accordance with Table 500-5(d)." SUBSTANTIATION: It is incorrect to refer to the temperature identification numbers are indicating a temperature range. IEC 790 and other NFPA documents such as NFPA 496 and NFPA 70NEC 505, refer to temperature identification numbers as "T codes" which are a recognized type of temperature classification. The suggested changes agree with this usage. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #2610) 14- 51 - (500-5(d)): Accept in Part SUBMITTER: Donald R. Cook, Southern Section, IAEI RECOMMENDATION: Revise text to read as follows: (d) Marking. Approved (Identified) equipment shall be marked to show the class, group, and operating temperature or temperature range referened to a 40°C ambient.

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SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. Delete the word "approved". PANEL STATEMENT: Marking is already required. See also Proposal 14-2a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3468) 14- 52 - (500-5(d)): Accept in Part SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (d) Marking. Approved (Identified) equipment shall be marked to show the class, group, and operating temperature or temperature range referenced to a 40°C ambient. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. Delete the word "approved". PANEL STATEMENT: Marking is already required. See also Proposal 14-2a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3469) 14- 53 - (500-5(d)): Accept in Principle in Part SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the fourth paragraph to read as follows: "Equipment that is approved (identified) for Class I and Class II shall be marked with the maximum safe operating temperature, as determined by simultaneous exposure to eh combinations of Class I and Class II conditions." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle in Part. Delete the words "that is appproved". PANEL STATEMENT: Marking is already required. See also Proposal 14-2a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________

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(Log #1964) 14- 54 - (500-5(f)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise paragraph two as follows: The ignitition temperature for which equipment was approved (identified) prior to this requirement shall be assumed to be as shown in Table 500-5(f). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: This section of the code refers to prior approvals, not new installations. Here, "approved" is the correct word. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3470) 14- 55 - (500-5(f)): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: "The ignition temperature for which equipment was approved (identified) prior to this requirement shall be assumed to be as shown in Table 500-5(f)." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: This section of the code refers to prior approvals, not new installations. Here, "approved" is the correct word. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #2338) 14- 56 - (500-7): Reject SUBMITTER: Mark Ptashkin, City of Phoenix, AZ RECOMMENDATION: Revise Section 500-7 to read as follows: Class I Locations. Class I locations are those in which Class I (flammable) liquids or Class II (combustible) liquids whose temperatures are above their flash points are housed, stored or used that are or may be present in the air in quantities sufficient to produce explosive or ignitable mixtures. Class I locations shall include those specified in (a) and (b). SUBSTANTIATION: This section presently does not address Class II liquids that are used, stored or handled in ambient temperatures above their flash point, this could be outside or even inside a structure. An example would be a liquid with a flash point of 105°F. used in and area that has a 110 degree ambient temperature. At this temperature the combustible liquid will take on the properties of a flammable liquid at a lower temperature. This is a concern in the southwestern United States, and other areas or buildings that have an ambient temperature above the flash point of combustible liquids that may be present. For instance, some jet fuels have a flash point right at 100 degrees F. In many locations throughout the southwest it is common to be well above 100 degrees for more than 8 hours. There is justification for this proposal in NEC 513-1, NEC 514-1 FPN N0. 1, NEC 515-1. FPN, NEC 516-1, and NFPA 30, 1996 Flammable and combustible liquids code 5-9.5.1 and which states

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"This section shall apply to areas where Class I liquids are stored or handled and to areas where Class II or Class III liquids are stored or handled at temperatures above their flash points (see 11.3)." 5-9.5.2 "Electrical wiring and utilization equipment shall be designed and installed in accordance with NFPA 70, National Electrical Code, and this section. Electrical wiring and utilization equipment in classified locations shall be designed and installed in accordance with Chapter 5 of NFPA 70." The NEC does not currently help the electrical community by clearly addressing combustible liquids. We should not have to rifle through multiple standards to solve a simple problem. This would enable the NEC to address this issue. All of the above make some reference that a combustible liquid that is above its flash point is a hazard. PANEL ACTION: Reject. PANEL STATEMENT: Areas other than those containing Class I or II liquids may need to be classified. NFPA 497 addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3416) 14- 57 - (500-7(b)): Reject SUBMITTER: Nicholas T. Abbatiello, Spencerport, NY RECOMMENDATION: Add a subparagraph (4) to read: "Locations, within enclosed equipment and machines in industrial establishments where the conditions of design, maintenance and supervision ensure that only qualified persons will build and service the installation, not complying with (1) through (3) which otherwise would be designated as Division 1 shall be permitted to be classified to Division 2: (i) when maintained at or below 25 percent of the Lower Flammable Limit, or (ii) where the electrical equipment, not rated for Division 1 but only rated for Division 2, is reliably interlocked by Listed and Labeled flammable gas detectors which will deenergize the equipment if 60 percent of the Lower Flammable Limit is exceeded. Consideration shall be given to rate at which the concentration can reach 100 percent versus the time for the deenergized equipment to come to a safe state. FPN: For additional information, refer to NFPA 69-1997, Explosion Prevention Systems, and ISA S84.01-1996, Application of Safety Instrumented Systems for Process Industries. SUBSTANTIATION: The current requirements do not address machinery interiors where protection against hazards, such as deflagration, by concentration reduction of the flammable gas or vapor. NFPA 34, Flammable or Combustible Liquids, Dipping and Coating Process, 1995, and Article 516, Spray Application, Dipping, and Coating Processes require interiors to be Division 1. NFPA 69 recognizes the 25 percent or below control and above 60 percent deenergization for protection against deflagration. Why can't there then be allowance for Division 2 equipment since the concentration is not normally flammable? This would provide equivalent safety as the likelihood, rather than the consequence, of an ignition in explosionproof equipment is reduced. PANEL ACTION: Reject. PANEL STATEMENT: The text proposed is too vague. The submitter has not addressed all of the issues pertinent to area classification when using gas detection equipment, as detailed in the referenced standards. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #CP1410) 14- 57a - (500-8(a), FPN (New) ): Accept SUBMITTER: CMP 14 RECOMMENDATION: Add a new FPN under 500-8(a) in Proposal 14-2a (CP1401) to read: "FPN: Switches, circuit breakers, plugs and receptacles, lighting fixtures, and other heat-producing apparatus are considered to be sources of ignition and are investigated for suitability in classified locations. Such types of equipment, as well as cable terminations for entry into explosionproof enclosures, are available as listed for Division 2. Fixed wiring, however, may utilize nonhazardous location wiring

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methods that are not evaluated with respect to classified locations. Wiring products such as cable, raceways, boxes, and fittings, therefore, are not marked as being suitable for Division 2. Also see Exception No. 3 to 500-8(b)." SUBSTANTIATION: Assists in clarifying the use of general purpose equipment in Division 2 locations, without the need for it being identified specifically for Division 2. PANEL ACTION: Accept. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 9 NEGATIVE: 3 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: GOODMAN: The use of the term "nonhazardous location" is confusing and not required. As indicated in the Substantiation, the term "general purpose" is acknowledged as the proper term and would provide a clearer description if wording were deemed necessary. Preferably, simply delete the term "nonhazardous location" to have the sentence read: "Fixed wiring, however, may utilize wiring methods that are not evaluated with respect to classified locations." LAWRENCE: My records of the meeting do not support the panel action. The text as shown does not correlate with the text at the indicated location of insertion. WECHSLER: My notes do not support the panel action shown for panel action on this specific proposal. The reference to adding the proposed fine print note to Section 500-8(a) does not appear to fit the existing text, nor does it appear to agree with the revised Article 500 rewrite. COMMENT ON AFFIRMATIVE: JAGUNICH: See ballot for David Wechsler. ZIPSE: I am in agreement with Mr. Goodman. However, it would be more advisable to save the panel proposal and change it during the comment stage than to remove the proposal from ever existing. ___________________ (Log #2130) 14- 58 - (500-10 (New) ): Accept in Principle SUBMITTER: Kari Barrett, Chemical Manufacturers Assn. RECOMMENDATION: Add new text to read as follows: 500-10. Unclassified Locations. Locations which are neither Class I, Division 1; Class I, Division 2, Class I, Zone 0; Class I, Zone 1; Class I, Zone 2; Class II, Division 1; Class II, Division 2; Class III, Division 1; Class III, Division 2, or any combination thereof. SUBSTANTIATION: The term "unclassified" is currently used at least 12 times in the NEC, but is not defined. While the terms "nonhazardous" and "unclassified" are used in both the NEC and other NFPA documents, the preferred term for area/location electrical classification is "unclassified" as it more clearly correlates with the condition of being reviewed but found not to need special electrical equipment for a specific electrically classified location. The term "nonhazardous" infers that the area has "no" hazards. This action provides needed correlation with other NFPA documents, such as NFPA 497 and NFPA 30. Additionally the term "nonhazardous" is used in at least in one other place in the NEC (i.e., Section 640-2) in which the meaning applies to voltages and not classification. A companion proposal has been made to change the term "nonhazardous" to "unclassified" elsewhere in the NEC and to define this term in Article 100 and 505. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________

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be noted that all of the other Code-Making Panels accepted the metrication directive. This action will be considered by the Panel as a Public Comment. SUBMITTER: Technical Correlating Committee National Electrical Code RECOMMENDATION: In 501-3(b)(6)(3), change "3 ft (914 mm)" to "900 mm (3 ft)". In 501-4(a)(1) Exception No. 1, change "2 in. (50.8 mm)" to "50 mm (2 in.)" in paragraph 1 of this exception; and change "24 in. (610 mm)" to "600 mm (24 in.)" in this exception in two places, one in each paragraph. In 501-5(a)(1), change "2 in." to "50 mm (2 in.)" and "18 in. (457 mm)" to "450 mm (18 in.)". In 501-5(a)(2), change "18 in. (457 mm)" to "450 mm (18 in.)". In 501-5(a)(3), change "36 in. (914 mm) to "900 mm (36 in.)" and "18 in. (457 mm)" to "450 mm (18 in.)" In 501-5(a)(4), change "10 ft (3.05 m)" to "3.0 m (10 ft)". In 501-5(a)(4) Exception change "12 ft (305 mm)" to "300 mm (12 in.)". In 501-5(b)(2), change "10 ft (3.05 m)" to "3.0 m (10 ft)". In 501-5(b)(2), Exception No. 1, change "12 in. (305 mm)" to "300 mm (12 in.)". In 501-5(b)(2), Exception No. 4(a), change "12 in. (305 mm)" to "300 mm (12 in.)". In 501-5(c)(3), change "5/8 in. (16 mm)" to "16 mm (5/8 in.)". In 501-5(d)(2), Exception, change "18 in. (457 mm)" to "450 mm (18 in.)". In 501-5(e)(2), change "[0.007 ft3/hour (198 cm3/hour) of air at a pressure of 6 in. of water (1493 pascals)]" to "[200 cm 3/hour (0.007 ft 3/hour) of air at a pressure of 1500 pascals (6 in. of water)]". In 501-5(e)(3), change "6 in. of water (1493 pascals)" to "1500 pascals (6 in. of water)." In 501-6(b)(1)(b), change "2-in. (50.8 mm)" to "50 mm (2 in.)" and "1 in. (25.4-mm)" to "25 mm (1 in.)". In 501-9(a)(3), change "12 in. (305 mm)" to "300 mm (12 in.)" in three places. In 501-9(b)(3), change "12 in. (305 mm)" to "300 mm (12 in.)" in three places. In 501-16(b), Exception (a), change "6 ft (1.83 m)" to "1.8 m (6 ft)". SUBSTANTIATION: The proposed revision complies with the NFPA 1M Manual of Style Section 4-1 with respect to the placement of units, i.e., to show the SI units as the preferred unit and the inch-pound units immediately following in parenthesis. PANEL ACTION: Reject. PANEL STATEMENT: Panel 14 believes the following issues need further evaluation before changes are made to the code. Trade sizes of conduit, extract policies, consistency from article to article within the code are all issues that need further evaluation. For example, trade size of conduit is not a true dimension and cannot be converted to a true metric number. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 9 NEGATIVE: 3 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: KUCZKA: See my Explanation of Negative Vote on Proposal 1410. OMEARA: The proposal should be accepted, to be in conformance with Chapter 4 of the NFPA MOS-1 Manual of Style. ZIPSE: See my Explanation of Negative Vote on Proposal 14-10. ___________________ (Log #CP1411) 14- 59a - (Article 501): Accept Note: The Technical Correlating Committee advises that Article Scope statements are the responsibility of the Technical Correlating Committee and the Technical Correlating Committee accepts the Panel Action. Further, it was the action of the Technical Correlating Committee that this Proposal be reconsidered by the Panel, with further consideration given to the comments expressed in the voting, specifically with respect to comments that the accepted Proposal does not accurately reflect what was agreed upon by the Panel. It is the understanding of the Technical Correlating Committee that this proposal is modified by Proposals 14-61, 14-62, 14-64, 14-66, 14-67, 14-68, 14-69, 14-70, 14-71, 14-72, 14-75, 14-77, 14-92, 14-93, 14-94, 14-95, 14-96, 14-98, 14-100, 14-101, 14-102, 14-103, 14-106, 14-107, 14-108, 14-109, 14-110, 14-111,

ARTICLE 501 -- CLASS I LOCATIONS

(Log #1259) 14- 59 - (501): Reject Note: It was the action of the Technical Correlating Committee that this Proposal be reconsidered by the Panel. The issues of raceway trade size, extracts, and use of soft versus hard metrication were all studied in detail and resolutions were communicated to the Panel prior to the Panel Meeting. It should

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14-116, 14-117, 14-118, 14-119, 14-130, 14-131, 14-132, 14-133, 14-134, 14-135, 14-140, 14-141, 14-142, 14-143, 14-144, 14-145, 14-146, 14-147, 14-149, 14-150, 14-151, 14-152, 14-153, 14-154, 14-155, 14-156, 14-157, 14-158, 14-162, 14-164, 14-165, 14-166, 14-168, 14-169, 14-170, 14-171, 14-172, 14-174, 14-175, 14-178, 14-179, 14-184, 14-185, 14-186, 14-187, 14-194, 14-195, 14-196, and 14-197. This action will be considered by the Panel as a Public Comment SUBMITTER: CMP 14 RECOMMENDATION: Revise Article 501 to read as follows: 501 ARTICLE 501 -- Class I Locations 501-1. General. The general rules of this Code shall apply to the electric wiring and equipment in locations classified as Class I in Section 500-7 5. Equipment listed and marked in accordance with Section 505-10 for use in Class I, Zone 0, 1, or 2 locations shall be permitted in Class I, Division 2 locations for the same gas and with a suitable temperature rating classification. Exception: As modified by this article. 501-2. Transformers and Capacitors (a) Class I, Division 1. In Class I, Division 1 locations, transformers and capacitors shall comply with the following. (1) Containing Liquid that Will Burn. Transformers and capacitors containing a liquid that will burn shall be installed only in approved vaults that comply with Sections 450-41 through 450-48, and, in addition, a. There shall be no door or other communicating opening between the vault and the Division 1 location, and b. Ample ventilation shall be provided for the continuous removal of flammable gases or vapors, and c. Vent openings or ducts shall lead to a safe location outside of buildings, and d. Vent ducts and openings shall be of sufficient area to relieve explosion pressures within the vault, and all portions of vent ducts within the buildings shall be of reinforced concrete construction. (2) Not Containing Liquid that Will Burn. Transformers and capacitors that do not contain a liquid that will burn shall be installed in vaults complying with (a)(1) or be approved for Class I locations. (b) Class I, Division 2. In Class I, Division 2 locations, transformers and capacitors shall comply with Sections 450-21 through 450-27. 501-3. Meters, Instruments, and Relays (a) Class I, Division 1. In Class I, Division 1 locations, meters, instruments, and relays, including kilowatt-hour meters, instrument transformers, resistors, rectifiers, and thermionic tubes, shall be provided with enclosures approved for Class I, Division 1 locations. Enclosures approved for Class I, Division 1 locations include explosionproof enclosures and purged and pressurized enclosures. FPN: See Standard for Purged and Pressurized Enclosures for Electrical Equipment, NFPA 496-1998. (b) Class I, Division 2. In Class I, Division 2 locations, meters, instruments, and relays shall comply with the following.

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temperature of any exposed surface will not exceed 80 percent of the ignition temperature in degrees Celsius of the gas or vapor involved or has been tested and found incapable of igniting the gas or vapor. This exception shall not apply to thermionic tubes. (3) Without Make-or-Break Contacts. Transformer windings, impedance coils, solenoids, and other windings that do not incorporate sliding or make-or-break contacts shall be provided with enclosures. General-purpose­type enclosures shall be permitted. (4) General-Purpose Assemblies. Where an assembly is made up of components for which general-purpose enclosures are acceptable as provided in (b)(1), (b)(2), and (b)(3), a single generalpurpose enclosure shall be acceptable for the assembly. Where such an assembly includes any of the equipment described in (b)(2), the maximum obtainable surface temperature of any component of the assembly shall be clearly and permanently indicated on the outside of the enclosure. Alternatively, approved equipment shall be permitted to be marked to indicate the temperature range class for which it is suitable, using the temperature class (T Code)identification numbers of Table 500-8 (b) 5(d) . (5) Fuses. Where general-purpose enclosures are permitted in (b)(1), (b)(2), (b)(3), and (b)(4), fuses for overcurrent protection of instrument circuits not subject to overloading in normal use shall be permitted to be mounted in general-purpose enclosures if each such fuse is preceded by a switch complying with (b)(1). (6) Connections. To facilitate replacements, process control instruments shall be permitted to be connected through flexible cord, attachment plug, and receptacle, provided the following: 1. A switch complying with (b)(1) is provided so that the attachment plug is not depended on to interrupt current; and 2. The current does not exceed 3 amperes at 120 volts, nominal; and 3. The power-supply cord does not exceed 3 ft (914 mm), is of a type approved for extra-hard usage or for hard usage if protected by location, and is supplied through an attachment plug and receptacle of the locking and grounding type; and 4. Only necessary receptacles are provided; and 5. The receptacle carries a label warning against unplugging under load. 501-4. Wiring Methods. Wiring methods shall comply with (a) or (b). (a) Class I, Division 1. (1) In Class I, Division 1 locations, the following wiring methods shall be permitted: a) Threaded rigid metal conduit or threaded steel intermediate metal conduit. Threaded joints shall be made up with at least five threads fully engaged.

Exception No. 1: Rigid nonmetallic conduit complying with Article 347 shall be permitted where encased in a concret e envelope a minimum of 2 in. (50.8 mm) thick and provided with not less than 24 in. (610 mm) of cover measured from the top of the conduit to (1) Contacts. Switches, circuit breakers, and make-and-break contacts of pushbuttons, relays, alarm bells, and horns shall have grade. The concrete encasement shall be permitted to be omitted enclosures approved for Class I, Division 1 locations in accordance where subject to the provisions of Section 511-4, Exception; 514-8, with Section 501-3(a). Exception No. 2; and Section 515-5(a). Threaded rigid metal Exception: General-purpose enclosures shall be permitted, if conduit or threaded steel intermediate metal conduit shall be used current-interrupting contacts are for the last 24 in. (610 mm) of the underground run to emergence a. Immersed in oil, or or to the point of connection to the aboveground raceway. An b. Enclosed within a chamber that is hermetically sealed equipment grounding conductor shall be included to provide for against the entrance of gases or vapors, or electrical continuity of the raceway system and for grounding of c. In nonincendive circuits, or d. Part of a listed nonincendive component. noncurrent-carrying metal parts. (2) Resistors and Similar Equipment. Resistors, resistance devices, thermionic tubes, rectifiers, and similar equipment that are used in or in connection with meters, instruments, and relays shall comply with Section 501-3(a). Exception: General-purpose­type enclosures shall be permitted if such equipment is without make-and-break or sliding contacts [other than as provided in (b)(1)] and if the maximum operating b) Type MI cable with termination fittings approved for the location. Type MI cable shall be installed and supported in a manner to avoid tensile stress at the termination fittings. c) In industrial establishments with restricted public access, where the conditions of maintenance and supervision

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ensure that only qualified persons w ill service the installation Type MC-HL cable, listed for use in Class I, Division 1 locations, with a gas/vaportight continuous corrugated metallic (14-78) sheath, an overall jacket of suitable polymeric material, separate grounding conductors in accorda nce with Section 250-122, and provided with termination fittings listed for the application. FPN: See Sections 334-3 and 334-4 for restrictions on use of Type MC cable. d) In industrial establishments with restricted public access, where the conditions o f maintenance and supervision ensure that only qualified persons will service the installation, Type ITC-HL cable, listed for use in Class I, Division 1 locations, with a gas/vaportight continuous corrugated metallic sheath, an overall jacket of suitable polymeric material and provided with termination fittings listed for the application. (2) Where necessary to employ flexible connections, as at motor terminals, flexible fittings listed for Class I, Division 1 locations or flexible cord in accordance with the provisions of Section 501-11 shall be permitted. (3) All boxes, fittings, and joints shall be approved for Class I, Division 1. (b) Class I, Division 2. (1) In Class I, Division 2 locations, the following wiring methods shall be permitted: a) Threaded rigid metal conduit, threaded steel intermediate metal conduit, b) Enclosed gasketed busways, enclosed gasketed wireways, c) Type PLTC cable in accordance with the provisions of Article 725, or in cable tray systems. PLTC shall be installed in a mann er to avoid tensile stress at the termination fittings. d) Type ITC cable in cable trays, in raceways, supported by messenger wire, afforded mechanical protection and run as open wiring, or directly buried where the cable is listed for this use; e) Type MI, MC, MV, or TC cable with (14-79/14-80) termination fittings, or in cable tray systems and installed in a manner to avoid tensile stress at the termination fittings. (2) Where provision must be made for limited flexibility, flexible metal fittings, flexible metal conduit with listed fittings, liquidtight flexible metal conduit with listed fittings, liquidtight flexible nonmetallic conduit with listed fittings, or flexible cord listed for extra-hard usage and provided with listed bushed fittings shall b e used. An additional conductor for grounding shall be included in the flexible cord. (14-87) FPN: See Section 501-16(b) for grounding requirements where flexible conduit is used. FPN ?? ( 3) Nonincendive field wiring shall be permitted using any of the wir ing methods permitted for nonhazardous (14-88/1401) locations, including Chapter 7 and 8 wiring methods. Nonincendive field wiring systems shall be installed in accordance with the control drawing(s). (14-83) ( 4) Boxes, fittings, and joints shall not be required to be explosionproof except as required by Sections 501-3(b)(1), 5016(b)(1), and 501-14(b)(1). 501-5. Sealing and Drainage Seals in conduit and cable systems shall comply with (a) through (f). Sealing compound shall be of a type approved for the conditions and use (14-89). Sealing compound shall be used in Type MI cable termination fittings to exclude moisture and other fluids from the cable insulation. FPN No. 1: Seals are provided in conduit and cable systems to minimize the passage of gases and vapors and prevent the passage of flames from one portion of the electrical installation to another through the conduit. Such communication through Type MI cable is

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inherently prevented by construction of the cable. Unless specifically designed and tested for the purpose, conduit and cable seals are not intended to prevent the passage of liquids, gases, or vapors at a continuous pressure differential across the seal. Even at differences in pressure across the seal equivalent to a few inches of water, there may be a slow passage of gas or vapor through a seal, and through conductors passing through the seal. See Section 501-5(e)(2). Temperature extremes and highly corrosive liquids and vapors can affect the ability of seals to perform their intended function. See Section 5015(c)(2). FPN No. 2: Gas or vapor leakage and propagation of flames may occur through the interstices between the strands of standard stranded conductors larger than No. 2. Special conductor constructions, e.g., compacted strands or sealing of the individual strands, are means of reducing leakage and preventing the propagation of flames.

(a) Conduit Seals, Class I, Division 1. In Class I, Division 1 locations, conduit seals shall be located as follows. 1. In each conduit entry into an explosionproof enclosure where either (a) the enclosure contains apparatus, such as switches, circuit breakers, fuses, relays, or resistors, that may produce arcs, sparks, or high temperatures that are considered to be an ignition source in normal operation, or (b) the entry is 2-in. size or larger and the enclosure contains terminals, splices, or taps. For the purposes of this section high temperatures shall be considered to be any temperatures exceeding 80 percent of the autoignition temperature in degrees Celsius of the gas or vapor involved. Exception to (a)(1)(a): Conduit entering an enclosure where such switches, circuit breakers, fuses, relays, or resistors are a. Enclosed within a chamber hermetically sealed against the entrance of gases or vapors, or b. Immersed in oil in accordance with Section 5016(b)(1)(b), or c. Enclosed within a factory-sealed explosionproof chamber located within the enclosure, approved for the location, and marked "factory sealed" or equivalent. Factory-sealed enclosures shall not be considered to serve as a seal for another adjacent explosionproof enclosure that is required to have a conduit seal. Conduit seals shall be installed within 18 in. (457 mm) from the enclosure. Only explosionproof unions, couplings, reducers, elbows, capped elbows, and conduit bodies similar to L, T, and Cross types that are not larger than the trade size of the conduit shall be permitted between the sealing fitting and the explosionproof enclosure. 2. In each conduit entry into a pressurized enclosure where the conduit is not pressurized as part of the protection system. Conduit seals shall be installed within 18 in. (457 mm) from the pressurized enclosure. FPN No. 1: Installing the seal as close as possible to the enclosure will reduce problems with purging the dead airspace in the pressurized conduit. FPN No. 2: For further information, see Standard for Purged and Pressurized Enclosures for Electrical Equipment, NFPA 496-1998. 3. Where two or more explosionproof enclosures for which conduit seals are required under (a)(1) are connected by nipples or by runs of conduit not more than 36 in. (914 mm) long, a single conduit seal in each such nipple connection or run of conduit shall be considered sufficient if located not more than 18 in. (457 mm) from either enclosure. 4. In each conduit run leaving a Class I, Division 1 location. The sealing fitting shall be permitted on either side of the boundary of such location within 10 ft (3.05 m) of the boundary, and shall be designed and installed so to minimize the amount of gas or vapor within the Division 1 portion of the conduit from being communicated to the conduit beyond the seal. Except for approved explosionproof reducers at the conduit seal, there shall be no union, coupling, box, or fitting between the conduit seal and the point at which the conduit leaves the Division 1 location. Exception: Metal conduit containing no unions, couplings, boxes, or fittings that passes completely through a Class I, Division 1 location with no fittings less than 12 in. (305 mm) beyond each

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boundary shall not require a conduit seal if the termination points of the unbroken conduit are in unclassified locations. (b) Conduit Seals, Class I, Division 2. In Class I, Division 2 locations, conduit seals shall be located as follows. 1. For connections to enclosures that are required to be explosionproof, a conduit seal shall be provided in accordance with (a)(1)(a) and (a)(3). All portions of the conduit run or nipple between the seal and such enclosure shall comply with Section 501-4(a). 2. In each conduit run passing from a Class I, Division 2 location into an unclassified location. The sealing fitting shall be permitted on either side of the boundary of such location within 10 ft (3.05 m) of the boundary, and shall be designed and installed so to minimize the amount of gas or vapor within the Division 2 portion of the conduit from being communicated to the conduit beyond the seal. Rigid metal conduit or threaded steel intermediate metal conduit shall be used between the sealing fitting and the point at which the conduit leaves the Division 2 location, and a threaded connection shall be used at the sealing fitting. Except for approved explosionproof reducers at the conduit seal, there shall be no union, coupling, box, or fitting between the conduit seal and the point at which the conduit leaves the Division 2 location. Exception No. 1: Metal conduit containing no unions, couplings, boxes or fittings that passes completely through a Class I, Division 2 location with no fittings less than 12 in. (305 mm) beyond each boundary shall not be required to be sealed if the termination points of the unbroken conduit are in unclassified locations. Exception No. 2: Conduit systems terminating at an unclassified location where a wiring method transition is made to cable tray, cablebus, ventilated busway, Type MI cable, or open wiring shall not be required to be sealed where passing from the Class I, Division 2 location into the unclassified location. The unclassified location shall be outdoors or, if the conduit system is all in one room, it shall be permitted to be indoors. The conduits shall not terminate at an enclosure containing an ignition source in normal operation. Exception No. 3: Conduit systems passing from an enclosure or room that is unclassified as a result of pressurization into a Class I, Division 2 location shall not require a seal at the boundary. FPN: For further information, refer to Standard for Purged and Pressurized Enclosures for Electrical Equipment, NFPA 496-1998. Exception No. 4: Segments of aboveground conduit systems shall not be required to be sealed where passing from a Class I, Division 2 location into an unclassified location if the following conditions are met: a. No part of the conduit system segment passes through a Class I, Division I location where the conduit contains unions, couplings, boxes, or fittings within 12 in. (305 mm) of the Class I, Division 1 location; and b. The conduit system segment is located entirely in outdoor locations; and c. The conduit system segment is not directly connected to canned pumps, process or service connections for flow, pressure, or analysis measurement, etc., that depend on a single compression seal, diaphragm, or tube to prevent flammable or combustible fluids from entering the conduit system; and d. The conduit system segment contains only threaded metal conduit, unions, couplings, conduit bodies, and fittings in the unclassified location; and e. The conduit system segment is sealed at its entry to each enclosure or fitting housing terminals, splices, or taps in Class I, Division 2 locations. (c) Class I, Divisions 1 and 2. Where required, seals in Class I, Division 1 and 2 locations shall comply with the following. (1) Fittings. Enclosures for connections or equipment shall be provided with an approved integral means for sealing, or sealing fittings approved for Class I locations shall be used. Sealing fittings shall be accessible. Sealing fittings shall be listed for use with one or more specific compounds and shall b e accessible. (14-104, 14-105) (2) Compound. The compound shall provide a Sealing compound shall be approved and shall provide a seal against passage of gas or

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vapors through the seal fitting, shall not be affected by the surrounding atmosphere or liquids, and shall not have a melting point of less than 93ºC (200ºF). (14-104) (3) Thickness of Compounds. In a completed seal, the minimum thickness of the sealing compound shall not be less than the trade size of the sealing fitting and, in no case, less than 5/8 in. (16 mm). Exception: Listed cable sealing fittings shall not be required to have a minimum thickness equal to the trade size of the fitting. (4) Splices and Taps. Splices and taps shall not be made in fittings intended only for sealing with compound, nor shall other fittings in which splices or taps are made be filled with compound. (5) Assemblies. In an assembly where equipment that may produce arcs, sparks, or high temperatures is located in a compartment separate from the compartment containing splices or taps, and an integral seal is provided where conductors pass from one compartment to the other, the entire assembly shall be approved for Class I locations. Seals in conduit connections to the compartment containing splices or taps shall be provided in Class I, Division 1 locations where required by (a)(1)(b). (14(6) Conductor Fill. The cross-sectional area of the conductors permitted in a seal shall not exceed 25 percent of the crosssectional area of a rigid metal conduit of the same trade size unless it is specifically approved for a higher percentage of fill. (d) Cable Seals, Class I, Division 1. In Class I, Division 1 locations, cable seals shall be located as follows. 1. Cable shall be sealed at all terminations. The sealing fitting shall comply with (c). Multiconductor Type MC cables with a gas/vaportight continuous corrugated aluminum sheath and an overall jacket of suitable polymeric material shall be sealed with an approved fitting after removing the jacket and any other covering so that the sealing compound will surround each individual insulated conductor in such a manner as to minimize the passage of gases and vapors. Exception: Shielded cables and twisted pair cables shall not require the removal of the shielding material or separation of the twisted pairs provided the termination is by an approved means to minimize the entrance of gases or vapors and prevent propagation of flame into the cable core. 2. Cables in conduit with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall be sealed in the Division 1 location after removing the jacket and any other coverings so that the sealing compound will surround each individual insulated conductor and the outer jacket. Exception: Multiconductor cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall be permitted to be considered as a single conductor by sealing the cable in the conduit within 18 in. (457 mm) of the enclosure and the cable end within the enclosure by an approved means to minimize the entrance of gases or vapors and prevent the propagation of flame into the cable core, or by other approved methods. For shielded cables and twisted pair cables, it shall not be required to remove the shielding material or separate the twisted pair. 3. Each multiconductor cable in conduit shall be considered as a single conductor if the cable is incapable of transmitting gases or vapors through the cable core. These cables shall be sealed in accordance with (a). (e) Cable Seals, Class I, Division 2 . In Class I, Division 2 locations, cable seals shall be located as follows. 1. Cables entering enclosures that are required to be approved for Class I locations shall be sealed at the point of entrance. The sealing fitting shall comply with (b)(1). Multiconductor cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall be sealed in an approved fitting in the Division 2 location after removing the jacket and any other coverings so that the sealing compound will surround each individual insulated conductor in such a manner as to minimize the passage of gases and vapors. Multiconductor cables in conduit shall be sealed as described in (d). Exception No. 1: Cables passing from an enclosure or room that is unclassified as a result of Type Z pressurization into a Class I, Division 2 location shall not require a seal at the boundary. Exception No. 2: Shielded cables and twisted pair cables shall not require the removal of the shielding material or separation of the twisted pairs provided the termination is by an approved means to minimize the entrance of gases or vapors and prevent propagation of flame into the cable core.

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2. Cables with a gas/vaportight continuous sheath and that will not transmit gases or vapors through the cable core in excess of the quantity permitted for seal fittings shall not be required to be sealed except as required in (e)(1). The minimum length of such cable run shall not be less than that length that limits gas or vapor flow through the cable core to the rate permitted for seal fittings [0.007 ft 3 /hour (198 cm3 /hour) of air at a pressure of 6 in. of water (1493 pascals)]. FPN No. 1: See Outlet Boxes and Fittings for Use in Hazardous (Classified) Locations, ANSI/UL 886-1994. FPN No. 2: The cable core does not include the interstices of the conductor strands. 3. Cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall not be required to be sealed except as required in (e)(1), unless the cable is attached to process equipment or devices that may cause a pressure in excess of 6 in. of water (1493 pascals) to be exerted at a cable end, in which case a seal, barrier, or other means shall be provided to prevent migration of flammables into an unclassified area. Exception: Cables with an unbroken gas/vaportight continuous sheath shall be permitted to pass through a Class I, Division 2 location without seals. 4. Cables that do not have gas/vaportight continuous sheath shall be sealed at the boundary of the Division 2 and unclassified location in such a manner as to minimize the passage of gases or vapors into an unclassified location. FPN: The sheath mentioned in (d) and (e) may be either metal or a nonmetallic material. (f) Drainage. (1) Control Equipment. Where there is a probability that liquid or other condensed vapor may be trapped within enclosures for control equipment or at any point in the raceway system, approved means shall be provided to prevent accumulation or to permit periodic draining of such liquid or condensed vapor. (2) Motors and Generators. Where the authority having jurisdiction judges that there is a probability that liquid or condensed vapor may accumulate within motors or generators, joints and conduit systems shall be arranged to minimize entrance of liquid. If means to prevent accumulation or to permit periodic draining are judged necessary, such means shall be provided at the time of manufacture and shall be considered an integral part of the machine. (3) Canned Pumps, Process or Service Connections, etc. For canned pumps, process or service connections for flow, pressure, or analysis measurement, etc., that depend on a single compression seal, diaphragm, or tube to prevent flammable or combustible fluids from entering the electrical raceway or cable system capable of transmitting fluids, an additional approved seal, barrier, or other means shall be provided to prevent the flammable or combustible fluid from entering the raceway or cable system capable of transmitting fluids beyond the additional devices or means, if the primary seal fails. The additional approved seal or barrier and the interconnecting enclosure shall meet the temperature and pressure conditions to which they will be subjected upon failure of the primary seal, unless other approved means are provided to accomplish the purpose above. Drains, vents, or other devices shall be provided so that primary seal leakage will be obvious. FPN: See also the fine print notes to Section 501-5. 501-6. Switches, Circuit Breakers, Motor Controllers, and Fuses (a) Class I, Division 1. In Class I, Division 1 locations, switches, circuit breakers, motor controllers, and fuses, including pushbuttons, relays, and similar devices, shall be provided with enclosures, and the enclosure in each case, together with the enclosed apparatus, shall be approved as a complete assembly for use in Class I locations. (b) Class I, Division 2. Switches, circuit breakers, motor controllers, and fuses in Class I, Division 2 locations shall comply with the following: (1) Type Required. Circuit breakers, motor controllers, and switches intended to interrupt current in the normal performance of the function for which they are installed shall be provided with enclosures approved for Class I, Division 1 locations in accordance

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with Section 501-3(a), unless general-purpose enclosures are provided and a. The interruption of current occurs within a chamber hermetically sealed against the entrance of gases and vapors, or b. The current make-and-break contacts are oil-immersed and of the general-purpose type having a 2-in. (50.8-mm) minimum immersion for power contacts and a 1-in. (25.4-mm) minimum immersion for control contacts, or c. The interruption of current occurs within a factory-sealed explosionproof chamber approved for the location, or d. The device is a solid state, switching control without contacts, where the surface temperature does not exceed 80 percent of the ignition temperature in degrees Celsius of the gas or vapor involved. (2) Isolating Switches. Fused or unfused disconnect and isolating switches for transformers or capacitor banks that are not intended to interrupt current in the normal performance of the function for which they are installed shall be permitted to be installed in general-purpose enclosures. (3) Fuses. For the protection of motors, appliances, and lamps, other than as provided in (b)(4), standard plug or cartridge fuses shall be permitted, provided they are placed within enclosures identified approved (14-136) for the location; or fuses shall be permitted if they are within general-purpose enclosures, and if they are of a type in which the operating element is immersed in oil or other approved liquid, or the operating element is enclosed within a chamber hermetically sealed against the entrance of gases and vapors, or the fuse is a nonindicating, filled, current-limiting type. (4) Fuses Internal to Lighting Fixtures. Approved cartridge fuses shall be permitted as supplementary protection within lighting fixtures. 501-7. Control Transformers and Resistors Transformers, impedance coils, and resistors used as, or in conjunction with, control equipment for motors, generators, and appliances shall comply with (a) and (b). (a) Class I, Division 1. In Class I, Division 1 locations, transformers, impedance coils, and resistors, together with any switching mechanism associated with them, shall be provided with enclosures approved for Class I, Division 1 locations in accordance with Section 501-3(a). (b) Class I, Division 2. In Class I, Division 2 locations, control transformers and resistors shall comply with the following. (1) Switching Mechanisms. Switching mechanisms used in conjunction with transformers, impedance coils, and resistors shall comply with Section 501-6(b). (2) Coils and Windings. Enclosures for windings of transformers, solenoids, or impedance coils shall be permitted to be of the general-purpose type. (3) Resistors. Resistors shall be provided with enclosures; and the assembly shall be approved for Class I locations, unless resistance is nonvariable and maximum operating temperature, in degrees Celsius, will not exceed 80 percent of the ignition temperature of the gas or vapor involved, or has been tested and found incapable of igniting the gas or vapor. 501-8. Motors and Generators (a) Class I, Division 1. In Class I, Division 1 locations, motors, generators, and other rotating electric machinery shall be as follows: 1. Approved for Class I, Division 1 locations; or 2. Of the totally enclosed type supplied with positive-pressure ventilation from a source of clean air with discharge to a safe area, so arranged to prevent energizing of the machine until ventilation has been established and the enclosure has been purged with at least 10 volumes of air, and also arranged to automatically deenergize the equipment when the air supply fails; or 3. Of the totally enclosed inert gas-filled type supplied with a suitable reliable source of inert gas for pressuring the enclosure, with devices provided to ensure a positive pressure in the enclosure and arranged to automatically de-energize the equipment when the gas supply fails; or 4. Of a type designed to be submerged in a liquid that is flammable only when vaporized and mixed with air, or in a gas or vapor at a pressure greater than atmospheric and that is flammable only when mixed with air; and the machine is arranged so to prevent energizing it until it has been purged with the liquid or gas to exclude air, and also arranged to automatically de-energize the

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equipment when the supply of liquid or gas or vapor fails or the pressure is reduced to atmospheric. Totally enclosed motors of Types (2) or (3) shall have no external surface with an operating temperature in degrees Celsius in excess of 80 percent of the ignition temperature of the gas or vapor involved. Appropriate devices shall be provided to detect and automatically de-energize the motor or provide an adequate alarm if there is any increase in temperature of the motor beyond designed limits. Auxiliary equipment shall be of a type approved for the location in which it is installed. FPN: See ASTM Test Procedure, D 2155-69. (b) Class I, Division 2. In Class I, Division 2 locations, motors, generators, and other rotating electric machinery in which are employed sliding contacts, centrifugal or other types of switching mechanism (including motor overcurrent, overloading, and overtemperature devices), or integral resistance devices, either while starting or while running, shall be approved for Class I, Division 1 locations, unless such sliding contacts, switching mechanisms, and resistance devices are provided with enclosures approved for Class I, Division 2 locations in accordance with Section 501-3(b). The exposed surface of space heaters used to prevent condensation of moisture during shutdown periods shall not exceed 80 percent of the ignition temperature in degrees Celsius of the gas or vapor involved when operated at rated voltage, and the maximum surface temperature [based on a 40ºC (104ºF) ambient] shall be permanently marked on a visible nameplate mounted on the motor. Otherwise, space heaters shall be approved for Class I, Division 2 locations. In Class I, Division 2 locations, the installation of open or nonexplosionproof enclosed motors, such as squirrel-cage induction motors without brushes, switching mechanisms, or similar arc-producing devices that are not identified for use in a Class I, Division 2 location, shall be permitted. FPN No. 1: It is important to consider the temperature of internal and external surfaces that may be exposed to the flammable atmosphere. FPN No. 2: It is important to consider the risk of ignition due to currents arcing across discontinuities and overheating of parts in multisection enclosures of large motors and generators. Such motors and generators may need equipotential bonding jumpers across joints in the enclosure and from enclosure to ground. Where the presence of ignitible gases or vapors is suspected, cleanair purging may be needed immediately prior to and during startup periods. 501-9. Lighting Fixtures Lighting fixtures shall comply with (a) or (b). (a) Class I, Division 1. In Class I, Division 1 locations, lighting fixtures shall comply with the following. (1) Approved Fixtures. Each fixture shall be approved as a complete assembly for the Class I, Division 1 location and shall be clearly marked to indicate the maximum wattage of lamps for which it is approved. Fixtures intended for portable use shall be specifically approved as a complete assembly for that use. (2) Physical Damage. Each fixture shall be protected against physical damage by a suitable guard or by location. (3) Pendant Fixtures. Pendant fixtures shall be suspended by and supplied through threaded rigid metal conduit stems or threaded steel intermediate conduit stems, and threaded joints shall be provided with set-screws or other effective means to prevent loosening. For stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of a fitting or flexible connector approved for the Class I, Division 1 location shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting. (4) Supports. Boxes, box assemblies, or fittings used for the support of lighting fixtures shall be approved for Class I locations. (b) Class I, Division 2. In Class I, Division 2 locations, lighting fixtures shall comply with the following. (1) Portable Lighting Equipment. Portable lighting equipment shall comply with (a)(1). Exception: Where portable lighting equipment are mounted on movable stands and are connected by flexible cords, as covered in Section 501-11, they shall be permitted, where mounted in any position, if they conform to Section 501-9(b)(2). (2) Fixed Lighting. Lighting fixtures for fixed lighting shall be protected from physical damage by suitable guards or by location. Where there is danger that falling sparks or hot metal from lamps or fixtures might ignite localized concentrations of flammable

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vapors or gases, suitable enclosures or other effective protective means shall be provided. Where lamps are of a size or type that may, under normal operating conditions, reach surface temperatures exceeding 80 percent of the ignition temperature in degrees Celsius of the gas or vapor involved, fixtures shall comply with (a)(1) or shall be of a type that has been tested in order to determine the marked operating temperature or temperature class range (T Code) . (3) Pendant Fixtures. Pendant fixtures shall be suspended by threaded rigid metal conduit stems, threaded steel intermediate metal conduit stems, or by other approved means. For rigid stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of an approved fitting or flexible connector shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting. (4) Switches. Switches that are a part of an assembled fixture or of an individual lampholder shall comply with Section 501-6(b)(1). (5) Starting Equipment. Starting and control equipment for electric-discharge lamps shall comply with Section 501-7(b). Exception: A thermal protector potted into a thermally protected fluorescent lamp ballast if the lighting fixture is approved for locations of this class and division. 501-10. Utilization Equipment (a) Class I, Division 1. In Class I, Division 1 locations, all utilization equipment shall be approved for Class I, Division 1 locations. (b) Class I, Division 2. In Class I, Division 2 locations, all utilization equipment shall comply with the following. (1) Heaters. Electrically heated utilization equipment shall conform with either item (a) or (b). a. The heater shall not exceed 80 percent of the ignition temperature in degrees Celsius of the gas or vapor involved on any surface that is exposed to the gas or vapor when continuously energized at the maximum rated ambient temperature. If a temperature controller is not provided, these conditions shall apply when the heater is operated at 120 percent of rated voltage. Exception No. 1: For motor-mounted anticondensation space heaters, see Section 501-8(b). Exception No. 2: A current-limiting device is applied to the circuit serving the heater that will limit the current in the heater to a value less than that required to raise the heater surface temperature to 80 percent of the ignition temperature. b. The heater shall be approved for Class I, Division 1 locations. Exception: Electrical resistance heat tracing approved for Class I, Division 2 locations. (2) Motors. Motors of motor-driven utilization equipment shall comply with Section 501-8(b). (3) Switches, Circuit Breakers, and Fuses. Switches, circuit breakers, and fuses shall comply with Section 501-6(b). 501-11. Flexible Cords, Class I, Divisions 1 and 2 A flexible cord shall be permitted for connection between portable lighting equipment or other portable utilization equipment and the fixed portion of their supply circuit. Flexible cord shall also be permitted for that portion of the circuit where the fixed wiring methods of Section 501-4(a) cannot provide the necessary degree of movement for fixed and mobile electrical utilization equipment, in an industrial establishment where conditions of maintenance and engineering supervision ensure that only qualified persons will install and service the installation, and the flexible cord is protected by location or by a suitable guard from damage. The length of the flexible cord shall be continuous. Where flexible cords are used, the cords shall be as follows: 1. Of a type approved for extra-hard usage; 2. Contain, in addition to the conductors of the circuit, a grounding conductor complying with Section 400-23; 3. Connected to terminals or to supply conductors in an approved manner; 4. Be supported by clamps or by other suitable means in such a manner that there will be no tension on the terminal connections; and

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5. Be provided with suitable seals where the flexible cord enters boxes, fittings, or enclosures of the explosionproof type. Exception: As provided in Sections 501-3(b)(6) and 501-4(b). Electric submersible pumps with means for removal without entering the wet-pit shall be considered portable utilization equipment. The extension of the flexible cord within a suitable raceway between the wet-pit and the power source shall be permitted. Electric mixers intended for travel into and out of open-type mixing tanks or vats shall be considered portable utilization equipment. FPN: See Section 501-13 for flexible cords exposed to liquids having a deleterious effect on the conductor insulation. 501-12. Receptacles and Attachment Plugs, Class I, Divisions 1 and 2 Receptacles and attachment plugs shall be of the type providing for connection to the grounding conductor of a flexible cord and shall be approved for the location. Exception: As provided in Section 501-3(b)(6). 501-13. Conductor Insulation, Class I, Divisions 1 and 2 Where condensed vapors or liquids may collect on, or come in contact with, the insulation on conductors, such insulation shall be of a type approved for use under such conditions; or the insulation shall be protected by a sheath of lead or by other approved means. 501-14. Signaling, Alarm, Remote-Control, and Communications Systems (a) Class I, Division 1. In Class I, Division 1 locations, all apparatus and equipment of signaling, alarm, remote-control, and communications systems, regardless of voltage, shall be approved for Class I, Division 1 locations, and all wiring shall comply with Sections 501-4(a) and 501-5(a) and (c). (b) Class I, Division 2. In Class I, Division 2 locations, signaling, alarm, remote-control, and communications systems shall comply with the following. (1) Contacts. Switches, circuit breakers, and make-and-break contacts of pushbuttons, relays, alarm bells, and horns shall have enclosures approved for Class I, Division 1 locations in accordance with Section 501-3(a). Exception: General-purpose enclosures shall be permitted if current-interrupting contacts are one of the following: a. Immersed in oil, or b. Enclosed within a chamber hermetically sealed against the entrance of gases or vapors, or c. In nonincendive circuits, or d. Part of a listed nonincendive component (2) Resistors and Similar Equipment. Resistors, resistance devices, thermionic tubes, rectifiers, and similar equipment shall comply with Section 501-3(b)(2). (3) Protectors. Enclosures shall be provided for lightning protective devices and for fuses. Such enclosures shall be permitted to be of the general-purpose type. (4) Wiring and Sealing. All wiring shall comply with Sections 5014(b) and 501-5(b) and (c). 501-15. Live Parts, Class I, Divisions 1 and 2 There shall be no exposed live parts. 501-16. Grounding, Class I, Divisions 1 and 2 Wiring and equipment in Class I, Division 1 and 2 locations shall be grounded as specified in Article 250 and with the following additional requirements. (a) Bonding. The locknut-bushing and double-locknut types of contacts shall not be depended on for bonding purposes, but bonding jumpers with proper fittings or other approved means of bonding shall be used. Such means of bonding shall apply to all intervening raceways, fittings, boxes, enclosures, etc., between Class I locations and the point of grounding for service equipment or point of grounding of a separately derived system. Exception: The specific bonding means shall only be required to the nearest point where the grounded circuit conductor and the grounding electrode are connected together on the line side of the building or structure disconnecting means as specified in Sections 250-32(a), (b), and (c), provided the branch-circuit overcurrent protection is located on the load side of the disconnecting means. FPN: See Section 250-100 for additional bonding requirements in hazardous (classified) locations. (b) Types of Equipment Grounding Conductors. Where flexible metal conduit or liquidtight flexible metal conduit is used as permitted in Section 501-4(b) and is to be relied on to complete a

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sole equipment grounding path, it shall be installed with internal or external bonding jumpers in parallel with each conduit and complying with Section 250-102. Exception: In Class I, Division 2 locations, the bonding jumper shall be permitted to be deleted where all the following conditions are met. a. Listed liquidtight flexible metal conduit 6 ft (1.83 m) or less in length, with fittings listed for grounding, is used. b. Overcurrent protection in the circuit is limited to 10 amperes or less. c. The load is not a power utilization load. 501-17. Surge Protection (a) Class I, Division 1. Surge arresters, including their installation and connection, shall comply with Article 280. The surge arresters and capacitors shall be installed in enclosures approved for Class I, Division 1 locations. Surge-protective capacitors shall be of a type designed for specific duty. (b) Class I, Division 2. Surge arresters shall be nonarcing, such as metal-oxide varistor (MOV), sealed type, and surge-protective capacitors shall be of a type designed for specific duty. Installation and connection shall comply with Article 280. Enclosures shall be permitted to be of the general-purpose type. Surge protection of types other than described above shall be installed in enclosures approved for Class I, Division 1 locations. 501-18. Multiwire Branch Circuits In a Class I, Division 1 location, a multiwire branch circuit shall not be permitted. Exception: Where the disconnect device(s) for the circuit opens all ungrounded conductors of the multiwire circuit simultaneously. SUBSTANTIATION: This complete revision of Article 501 editorially revises the text to make it more easily understood and also incorporates numerous technical and editorial improvements made via other proposals. PANEL ACTION: Accept. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban COMMENT ON AFFIRMATIVE: BRIESCH: While the Panel Action to accept the rewrite of Article 501 is supported, the NFPA-circulated Panel Proposal does not include all of the changes agreed to at the meeting. The e-mail sent by Dave Wechsler subsequent to the meeting is more complete in reflecting the Panel Actions from the meeting. COOK: I agree with Proposal 14-59a and the substantiation, however, it does not incorporate all of the changes made via other proposals. An updated version that was emailed from Dave Wechsler on 1-26-2000 seems to be more complete with respect to including Panel Actions form the meeting in Hilton Head. ENGLER: Not all of the changes made it into the draft circulated with this ballot, vote is to affirm the text with all of the necessary changes made to it. JAGUNICH: See ballot for David Wechsler. LAWRENCE: Due to the large number of public proposals received and acted upon, and also due to time constraints, the panel was not able to compile and correlate all aspects of the rewrites of the affected article. Please see David Wechsler's ballot. OMEARA: Please see the comments on the ballot for David Wechsler. WECHSLER: While attempts were made to provide NFPA Staff with corrected revisions of this text before the end of the CMP 14 panel meeting, a detailed review of this balloted draft version has indicated that this does not reflect the accurate committee actions and is not correct. We attribute the problems with this draft to the following: a) the use of several earlier drafts that were consistently being revised to keep pace with changes made due to committee actions on public proposals, b) the limited time available to proof and develop this work, c) the extremely large number of public proposals, d) the complex nature of the interaction of affected texts within Articles 500, 501, 502 and 505, and the desire of the panel to maintain consistency, and e) human errors in transcribing this information. The following text provides a correct revision of this complete work effort for Article 501. This text should be the panel document of record and not that provided with the committee ballot.

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ARTICLE 501 -- Class I Locations 501-1. General. The general rules of this Code shall apply to the electric wiring and equipment in locations classified as Class I in Section 500-7 5. Equipment listed and marked in accordance with Section 505-10 for use in Class I, Zone 0, 1, or 2 locations shall be permitted in Class I, Division 2 locations for the same gas and with a suitable temperature rating classification. Exception: As modified by this article. 501-2. Transformers and Capacitors (a) Class I, Division 1. In Class I, Division 1 locations, transformers and capacitors shall comply with the following. (1) Containing Liquid that Will Burn. Transformers and capacitors containing a liquid that will burn shall be installed only in approved [14-61,14-62] vaults that comply with Sections 450-41 through 450-48, and, in addition, a. There shall be no door or other communicating opening between the vault and the Division 1 location, and b. Ample ventilation shall be provided for the continuous removal of flammable gases or vapors, and c. Vent openings or ducts shall lead to a safe location outside of buildings, and d. Vent ducts and openings shall be of sufficient area to relieve explosion pressures within the vault, and all portions of vent ducts within the buildings shall be of reinforced concrete construction. (2) Not Containing Liquid that Will Burn. Transformers and capacitors that do not contain a liquid that will burn shall be installed in vaults complying with (a)(1) or be approved for Class I locations. (b) Class I, Division 2. In Class I, Division 2 locations, transformers and capacitors shall comply with Sections 450-21 through 450-27. 501-3. Meters, Instruments, and Relays (a) Class I, Division 1. In Class I, Division 1 locations, meters, instruments, and relays, including kilowatt-hour meters, instrument transformers, resistors, rectifiers, and thermionic tubes, shall be provided with enclosures approved for Class I, Division 1 locations. Enclosures approved [14-66] for Class I, Division 1 locations include explosionproof enclosures and purged and pressurized enclosures. FPN: See Standard for Purged and Pressurized Enclosures for Electrical Equipment, NFPA 496-1998. (b) Class I, Division 2. In Class I, Division 2 locations, meters, instruments, and relays shall comply with the following.

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(4) General-Purpose Assemblies. Where an assembly is made up of components for which general-purpose enclosures are acceptable as provided in (b)(1), (b)(2), and (b)(3), a single generalpurpose enclosure shall be acceptable for the assembly. Where such an assembly includes any of the equipment described in (b)(2), the maximum obtainable surface temperature of any component of the assembly shall be clearly and permanently indicated on the outside of the enclosure. Alternatively, approved [14-69,14-70 ] equipment shall be permitted to be marked to indicate the temperature rangeclass for which it is suitable, using the temperature class (T Code)identification numbers of Table 500-8 (b)5(d) . (5) Fuses. Where general-purpose enclosures are permitted in (b)(1), (b)(2), (b)(3), and (b)(4), fuses for overcurrent protection of instrument circuits not subject to overloading in normal use shall be permitted to be mounted in general-purpose enclosures if each such fuse is preceded by a switch complying with (b)(1). (6) Connections. To facilitate replacements, process control instruments shall be permitted to be connected through flexible cord, attachment plug, and receptacle, provided the following: 1. A switch complying with (b)(1) is provided so that the attachment plug is not depended on to interrupt current; and 2. The current does not exceed 3 amperes at 120 volts, nominal; and 3. The power-supply cord does not exceed 3 ft (914 mm), is of a type listed approved [14-71,14-72 ] for extrahard usage or for hard usage if protected by location, and is supplied through an attachment plug and receptacle of the locking and grounding type; and 4. Only necessary receptacles are provided; and 5. The receptacle carries a label warning against unplugging under load. 501-4. Wiring Methods. Wiring methods shall comply with (a) or (b). [14-73 , 14-75 ,14-76 ,14-79 ] (b) Class I, Division 1. (1) In Class I, Division 1 locations, the following wiring methods shall be permitted: a) Threaded rigid metal conduit or threaded steel intermediate metal conduit. Threaded joints shall be made up with at least five threads fully engaged.

Exception No. 1: Rigid nonmetallic conduit complying with Article 347 shall be permitted where encased in a concrete envelope a minimum of 2 in. (50.8 mm) thick and provided with not less than 24 in. (610 mm) of cover measured from the top of the conduit to (1) Contacts. Switches, circuit breakers, and make-and-break contacts of pushbuttons, relays, alarm bells, and horns shall have grade. The concrete encasement shall be permitted to be omitted enclosures approved [14-67,14-68 ] for Class I, Division 1 locations where subject to the provisions of Section 511-4, Exception; 514-8, in accordance with Section 501-3(a). Exception No. 2; and Section 515-5(a). Threaded rigid metal Exception: General-purpose enclosures shall be permitted, if conduit or threaded steel intermediate metal conduit shall be used current-interrupting contacts are for the last 24 in. (610 mm) of the underground run to emergence a. Immersed in oil, or or to the point of connection to the aboveground raceway. An b. Enclosed within a chamber that is hermetically sealed equipment grounding conductor shall be included to provide for against the entrance of gases or vapors, or electrical continuity of the raceway system and for grounding of c. In nonincendive circuits, or noncurrent-carrying metal parts. d. Part of a listed nonincendive component. (2) Resistors and Similar Equipment. Resistors, resistance devices, thermionic tubes, rectifiers, and similar equipment that are used in or in connection with meters, instruments, and relays shall comply with Section 501-3(a). Exception: General-purpose­type enclosures shall be permitted if such equipment is without make-and-break or sliding contacts [other than as provided in (b)(1)] and if the maximum operating temperature of any exposed surface will not exceed 80 percent of the ignition temperature in degrees Celsius of the gas or vapor involved or has been tested and found incapable of igniting the gas or vapor. This exception shall not apply to thermionic tubes. (3) Without Make-or-Break Contacts. Transformer windings, impedance coils, solenoids, and other windings that do not incorporate sliding or make-or-break contacts shall be provided with enclosures. General-purpose­type enclosures shall be permitted. b) Type MI cable with termination fittings approved for the location. Type MI cable shall be installed and supported in a manner to avoid tensile stress at the termination fittings. [14-77] c) In industrial establishments with restricted public access, where the conditions of maintenance and supervision ensure that only qualified persons will service the installation Type MC-HL cable, listed for use in C lass I, Division 1 locations, with a gas/vaportight continuous corrugated metallic (14-78) sheath, an overall jacket of suitable polymeric material, separate grounding conductors in accordance with Section 250-122, and provided with termination fittings l isted for the application. FPN: See Sections 334-3 and 334-4 for restrictions on use of Type MC cable.

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d) In industrial establishments with restricted public access, where the conditions of maintenance and supervision ensure that only qualified persons w ill service the installation, Type ITC-HL cable, listed for use in Class I, Division 1 locations, with a gas/vaportight continuous corrugated metallic sheath, an overall jacket of suitable polymeric material and provided with termination fittings listed for the application. (2) Where necessary to employ flexible connections, as at motor terminals, flexible fittings listed for Class I, Division 1 locations or flexible cord in accordance with the provisions of Section 501-11 shall be permitted. (3) All box es, fittings, and joints shall be approved for Class I, Division 1. (b) Class I, Division 2. (1) In Class I, Division 2 locations, the following wiring methods shall be permitted: [14-83 ,14-86,14-87 ] a) Threaded rigid metal conduit, threaded steel intermediate metal conduit, b) Enclosed gasketed busways, enclosed gasketed wireways, c) Type PLTC cable in accordance with the provisions of Article 725, or in cable tray systems. PLTC shall be installed in a manner to avoid tensile stress at the termination fittings. d) Type ITC cable in cable trays, in raceways, supported by messenger wire, afforded mechanical protection and run as open wiring, or directly buried where the cable is listed for this use; e) Type MI, MC, MV, or TC cable with [14-79/14-80] termination fittings, or in cable tray systems and installed in a manner to avoid tensile stress at the termination fittings. (2) Where provision must be made for limited flexibility, flexible metal fittings, flexible metal conduit with listed fittings, liq uidtight flexible metal conduit with listed fittings, liquidtight flexible nonmetallic conduit with listed fittings, or flexible cord listed for extra-hard usage and provided with listed bushed fittings shall be used. An additional conductor for grounding shall be included in the flexible cord. [14-87 , 14-80 ] FPN: See Section 501-16(b) for grounding requirements where flexible conduit is used. ( 3) Nonincendive field wiring shall be permitted using any of the wiring methods permitted for nonhazardous [14-81 ,14-88,1401] locations, including Chapter 7 and 8 wiring methods. Nonincendive field wiring systems shall be installed in accordance with the control drawing(s). (14-83) ( 4) Boxes, fittings, and joints shall not be required to be explosionproof except as required by Sections 501-3(b)(1), 5016(b)(1), and 501-14(b)(1). 501-5. Sealing and Drainage Seals in conduit and cable systems shall comply with (a) through (f). Sealing compound shall be of a type approved for the conditions and use (14-89 ,14-91 ) . Sealing compound shall be used in Type MI cable termination fittings to exclude moisture and other fluids from the cable insulation. FPN No. 1: Seals are provided in conduit and cable systems to minimize the passage of gases and vapors and prevent the passage of flames from one portion of the electrical installation to another through the conduit. Such communication through Type MI cable is inherently prevented by construction of the cable. Unless specifically designed and tested for the purpose, conduit and cable seals are not intended to prevent the passage of liquids, gases, or vapors at a continuous pressure differential across the seal. Even at differences in pressure across the seal equivalent to a few inches of water, there may be a slow passage of gas or vapor through a seal, and through conductors passing through the seal. See Section 501-5(e)(2). Temperature extremes and highly corrosive liquids and vapors can affect the ability of seals to

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perform their intended function. See Section 5015(c)(2). FPN No. 2: Gas or vapor leakage and propagation of flames may occur through the interstices between the strands of standard stranded conductors larger than No. 2. Special conductor constructions, e.g., compacted strands or sealing of the individual strands, are means of reducing leakage and preventing the propagation of flames.

(a) Conduit Seals, Class I, Division 1. In Class I, Division 1 locations, conduit seals shall be located as follows. 1. In each conduit entry into an explosionproof enclosure where either (a) the enclosure contains apparatus, such as switches, circuit breakers, fuses, relays, or resistors, that may produce arcs, sparks, or high temperatures that are considered to be an ignition source in normal operation, or (b) the entry is 2-in. size or larger and the enclosure contains terminals, splices, or taps. For the purposes of this section high temperatures shall be considered to be any temperatures exceeding 80 percent of the autoignition temperature in degrees Celsius of the gas or vapor involved. Exception to (a)(1)(a): Conduit entering an enclosure where such switches, circuit breakers, fuses, relays, or resistors are a. Enclosed within a chamber hermetically sealed against the entrance of gases or vapors, or b. Immersed in oil in accordance with Section 5016(b)(1)(b), or c. Enclosed within a factory-sealed explosionproof chamber located within the enclosure, identified approved [14-92, 14-93 ] for the location, and marked "factory sealed" or equivalent. Factory-sealed enclosures shall not be considered to serve as a seal for another adjacent explosionproof enclosure that is required to have a conduit seal. Conduit seals shall be installed within 18 in. (457 mm) from the enclosure. Only explosionproof unions, couplings, reducers, elbows, capped elbows, and conduit bodies similar to L, T, and Cross types that are not larger than the trade size of the conduit shall be permitted between the sealing fitting and the explosionproof enclosure. d. In nonincendive circuits. [14-94] 2. In each conduit entry into a pressurized enclosure where the conduit is not pressurized as part of the protection system. Conduit seals shall be installed within 18 in. (457 mm) from the pressurized enclosure. FPN No. 1: Installing the seal as close as possible to the enclosure will reduce problems with purging the dead airspace in the pressurized conduit. FPN No. 2: For further information, see Standard for Purged and Pressurized Enclosures for Electrical Equipment, NFPA 496-1998. 3. Where two or more explosionproof enclosures for which conduit seals are required under (a)(1) are connected by nipples or by runs of conduit not more than 36 in. (914 mm) long, a single conduit seal in each such nipple connection or run of conduit shall be considered sufficient if located not more than 18 in. (457 mm) from either enclosure. 4. In each conduit run leaving a Class I, Division 1 location. The sealing fitting shall be permitted on either side of the boundary of such location within 10 ft (3.05 m) of the boundary, and shall be designed and installed so to minimize the amount of gas or vapor within the Division 1 portion of the conduit from being communicated to the conduit beyond the seal. Except for listed approved [14-95,14-96] explosionproof reducers at the conduit seal, there shall be no union, coupling, box, or fitting between the conduit seal and the point at which the conduit leaves the Division 1 location. Exception: Metal conduit containing no unions, couplings, boxes, or fittings that passes completely through a Class I, Division 1 location with no fittings less than 12 in. (305 mm) beyond each boundary shall not require a conduit seal if the termination points of the unbroken conduit are in unclassified locations. (b) Conduit Seals, Class I, Division 2. In Class I, Division 2 locations, conduit seals shall be located as follows. 1. For connections to enclosures that are required to be explosionproof, a conduit seal shall be provided in accordance with (a)(1)(a) and (a)(3). All portions of the conduit run or

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nipple between the seal and such enclosure shall comply with Section 501-4(a). 2. In each conduit run passing from a Class I, Division 2 location into an unclassified location. The sealing fitting shall be permitted on either side of the boundary of such location within 10 ft (3.05 m) of the boundary, and shall be designed and installed so to minimize the amount of gas or vapor within the Division 2 portion of the conduit from being communicated to the conduit beyond the seal. Rigid metal conduit or threaded steel intermediate metal conduit shall be used between the sealing fitting and the point at which the conduit leaves the Division 2 location, and a threaded connection shall be used at the sealing fitting. Except for listed approved [14-100,14-101] explosionproof reducers at the conduit seal, there shall be no union, coupling, box, or fitting between the conduit seal and the point at which the conduit leaves the Division 2 location. Exception No. 1: Metal conduit containing no unions, couplings, boxes or fittings that passes completely through a Class I, Division 2 location with no fittings less than 12 in. (305 mm) beyond each boundary shall not be required to be sealed if the termination points of the unbroken conduit are in unclassified locations. Exception No. 2: Conduit systems terminating at an unclassified location where a wiring method transition is made to cable tray, cablebus, ventilated busway, Type MI cable, or open wiring shall not be required to be sealed where passing from the Class I, Division 2 location into the unclassified location. The unclassified location shall be outdoors or, if the conduit system is all in one room, it shall be permitted to be indoors. The conduits shall not terminate at an enclosure containing an ignition source in normal operation. Exception No. 3: Conduit systems passing from an enclosure or room that is unclassified as a result of pressurization into a Class I, Division 2 location shall not require a seal at the boundary. FPN: For further information, refer to Standard for Purged and Pressurized Enclosures for Electrical Equipment, NFPA 496-1998. Exception No. 4: Segments of aboveground conduit systems shall not be required to be sealed where passing from a Class I, Division 2 location into an unclassified location if the following conditions are met: a. No part of the conduit system segment passes through a Class I, Division I location where the conduit contains unions, couplings, boxes, or fittings within 12 in. (305 mm) of the Class I, Division 1 location; and b. The conduit system segment is located entirely in outdoor locations; and c. The conduit system segment is not directly connected to canned pumps, process or service connections for flow, pressure, or analysis measurement, etc., that depend on a single compression seal, diaphragm, or tube to prevent flammable or combustible fluids from entering the conduit system; and d. The conduit system segment contains only threaded metal conduit, unions, couplings, conduit bodies, and fittings in the unclassified location; and e. The conduit system segment is sealed at its entry to each enclosure or fitting housing terminals, splices, or taps in Class I, Division 2 locations. (c) Class I, Divisions 1 and 2. Where required, seals in Class I, Division 1 and 2 locations shall comply with the following. (1) Fittings. Enclosures for connections or equipment shall be provided with an approved integral means for sealing, or sealing fittings approved for Class I locations shall be used. Sealing fittings shall be accessible. Sealing fittin gs shall be listed for use with one or more specific compounds and shall be accessible. (14-102,14103,14-104, 14-105) (2) Compound. The compound shall provide a Sealing compound shall be approved and shall provide a seal against passage of gas or vapors through the seal fitting, shall not be affected by the surrounding atmosphere or liquids, and shall not have a melting point of less than 93ºC (200ºF). (14-104 , 14-105) (3) Thickness of Compounds. In a completed seal, the minimum thickness of the sealing compound shall not be less than the trade

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size of the sealing fitting and, in no case, less than 5/8 in. (16 mm). Exception: Listed cable sealing fittings shall not be required to have a minimum thickness equal to the trade size of the fitting. (4) Splices and Taps. Splices and taps shall not be made in fittings intended only for sealing with compound, nor shall other fittings in which splices or taps are made be filled with compound. (5) Assemblies. In an assembly where equipment that may produce arcs, sparks, or high temperatures is located in a compartment separate from the compartment containing splices or taps, and an integral seal is provided where conductors pass from one compartment to the other, the entire assembly shall be identified approved for Class I locations. Seals in conduit connections to the compartment containing splices or taps shall be provided in Class I, Division 1 locations where required by (a)(1)(b). [14- 106, 14107] (6) Conductor Fill. The cross-sectional area of the conductors permitted in a seal shall not exceed 25 percent of the crosssectional area of a rigid metal conduit of the same trade size unless it is specifically identified approved [14-108,14-109] for a higher percentage of fill. (d) Cable Seals, Class I, Division 1. In Class I, Division 1 locations, cable seals shall be located as follows. 1. Cable shall be sealed at all terminations. The sealing fitting shall comply with (c). Multiconductor Type MC cables with a gas/vaportight continuous corrugated aluminum sheath and an overall jacket of suitable polymeric material shall be sealed with an listed approved [14-110,14-111] fitting after removing the jacket and any other covering so that the sealing compound will surround each individual insulated conductor in such a manner as to minimize the passage of gases and vapors. Exception: Shielded cables and twisted pair cables shall not require the removal of the shielding material or separation of the twisted pairs provided the termination is by an approved means to minimize the entrance of gases or vapors and prevent propagation of flame into the cable core. 2. Cables in conduit with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall be sealed in the Division 1 location after removing the jacket and any other coverings so that the sealing compound will surround each individual insulated conductor and the outer jacket. Exception: Multiconductor cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall be permitted to be considered as a single conductor by sealing the cable in the conduit within 18 in. (457 mm) of the enclosure and the cable end within the enclosure by an approved means to minimize the entrance of gases or vapors and prevent the propagation of flame into the cable core, or by other approved methods. For shielded cables and twisted pair cables, it shall not be required to remove the shielding material or separate the twisted pair. 3. Each multiconductor cable in conduit shall be considered as a single conductor if the cable is incapable of transmitting gases or vapors through the cable core. These cables shall be sealed in accordance with (a). (e) Cable Seals, Class I, Division 2 . In Class I, Division 2 locations, cable seals shall be located as follows. 1. Cables entering enclosures that are required to be explosionproof approved for Class I locations [14-116,14-118] shall be sealed at the point of entrance. The sealing fitting shall comply with (b)(1). Multiconductor cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall be sealed in an listed approved [14-117,14-119] fitting in the Division 2 location after removing the jacket and any other coverings so that the sealing compound will surround each individual insulated conductor in such a manner as to minimize the passage of gases and vapors. Multiconductor cables in conduit shall be sealed as described in (d). Exception No. 1: Cables passing from an enclosure or room that is unclassified as a result of Type Z pressurization into a Class I, Division 2 location shall not require a seal at the boundary. Exception No. 2: Shielded cables and twisted pair cables shall not require the removal of the shielding material or separation of the twisted pairs provided the termination is by an approved means to minimize the entrance of gases or vapors and prevent propagation of flame into the cable core.

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2. Cables with a gas/vaportight continuous sheath and that will not transmit gases or vapors through the cable core in excess of the quantity permitted for seal fittings shall not be required to be sealed except as required in (e)(1). The minimum length of such cable run shall not be less than that length that limits gas or vapor flow through the cable core to the rate permitted for seal fittings [0.007 ft3/hour (198 cm3/hour) of air at a pressure of 6 in. of water (1493 pascals)]. FPN No. 1: See Outlet Boxes and Fittings for Use in Hazardous (Classified) Locations, ANSI/UL 886-1994. FPN No. 2: The cable core does not include the interstices of the conductor strands. 3. Cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall not be required to be sealed except as required in (e)(1), unless the cable is attached to process equipment or devices that may cause a pressure in excess of 6 in. of water (1493 pascals) to be exerted at a cable end, in which case a seal, barrier, or other means shall be provided to prevent migration of flammables into an unclassified area. Exception: Cables with an unbroken gas/vaportight continuous sheath shall be permitted to pass through a Class I, Division 2 location without seals. 4. Cables that do not have gas/vaportight continuous sheath shall be sealed at the boundary of the Division 2 and unclassified location in such a manner as to minimize the passage of gases or vapors into an unclassified location. FPN: The sheath mentioned in (d) and (e) may be either metal or a nonmetallic material. (f) Drainage. (1) Control Equipment. Where there is a probability that liquid or other condensed vapor may be trapped within enclosures for control equipment or at any point in the raceway system, approved means shall be provided to prevent accumulation or to permit periodic draining of such liquid or condensed vapor. (2) Motors and Generators. Where the authority having jurisdiction judges that there is a probability that liquid or condensed vapor may accumulate within motors or generators, joints and conduit systems shall be arranged to minimize entrance of liquid. If means to prevent accumulation or to permit periodic draining are judged necessary, such means shall be provided at the time of manufacture and shall be considered an integral part of the machine. (3) Canned Pumps, Process or Service Connections, etc. For canned pumps, process or service connections for flow, pressure, or analysis measurement, etc., that depend on a single compression seal, diaphragm, or tube to prevent flammable or combustible fluids from entering the electrical raceway or cable system capable of transmitting fluids, an additional approved seal, barrier, or other means shall be provided to prevent the flammable or combustible fluid from entering the raceway or cable system capable of transmitting fluids beyond the additional devices or means, if the primary seal fails. The additional approved seal or barrier and the interconnecting enclosure shall meet the temperature and pressure conditions to which they will be subjected upon failure of the primary seal, unless other approved means are provided to accomplish the purpose above. Drains, vents, or other devices shall be provided so that primary seal leakage will be obvious. FPN: See also the fine print notes to Section 501-5. 501-6. Switches, Circuit Breakers, Motor Controllers, and Fuses (a) Class I, Division 1. In Class I, Division 1 locations, switches, circuit breakers, motor controllers, and fuses, including pushbuttons, relays, and similar devices, shall be provided with enclosures, and the enclosure in each case, together with the enclosed apparatus, shall be identified approved [14-130 , 14-131] as a complete assembly for use in Class I locations. (b) Class I, Division 2. Switches, circuit breakers, motor controllers, and fuses in Class I, Division 2 locations shall comply with the following: (1) Type Required. Circuit breakers, motor controllers, and switches intended to interrupt current in the normal performance of the function for which they are installed shall be provided with enclosures identified approved [14-132,14-133] for Class I, Division

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1 locations in accordance with Section 501-3(a), unless generalpurpose enclosures are provided and a. The interruption of current occurs within a chamber hermetically sealed against the entrance of gases and vapors, or b. The current make-and-break contacts are oil-immersed and of the general-purpose type having a 2-in. (50.8-mm) minimum immersion for power contacts and a 1-in. (25.4-mm) minimum immersion for control contacts, or c. The interruption of current occurs within a factory-sealed explosionproof chamber approved for the location[14-134, 14-135] , or d. The device is a solid state, switching control without contacts, where the surface temperature does not exceed 80 percent of the ignition temperature in degrees Celsius of the gas or vapor involved. (2) Isolating Switches. Fused or unfused disconnect and isolating switches for transformers or capacitor banks that are not intended to interrupt current in the normal performance of the function for which they are installed shall be permitted to be installed in general-purpose enclosures. (3) Fuses. For the protection of motors, appliances, and lamps, other than as provided in (b)(4), standard plug or cartridge fuses shall be permitted, provided they are placed within enclosures identified approved (14-136,14-137) for the location; or fuses shall be permitted if they are within general-purpose enclosures, and if they are of a type in which the operating element is immersed in oil or other approved liquid, or the operating element is enclosed within a chamber hermetically sealed against the entrance of gases and vapors, or the fuse is a nonindicating, filled, current-limiting type. (4) Fuses Internal to Lighting Fixtures. Approved cartridge fuses shall be permitted as supplementary protection within lighting fixtures. 501-7. Control Transformers and Resistors Transformers, impedance coils, and resistors used as, or in conjunction with, control equipment for motors, generators, and appliances shall comply with (a) and (b). (a) Class I, Division 1. In Class I, Division 1 locations, transformers, impedance coils, and resistors, together with any switching mechanism associated with them, shall be provided with enclosures identified approved [14-140,14-141] for Class I, Division 1 locations in accordance with Section 501-3(a). (b) Class I, Division 2. In Class I, Division 2 locations, control transformers and resistors shall comply with the following. (1) Switching Mechanisms. Switching mechanisms used in conjunction with transformers, impedance coils, and resistors shall comply with Section 501-6(b). (2) Coils and Windings. Enclosures for windings of transformers, solenoids, or impedance coils shall be permitted to be of the general-purpose type. (3) Resistors. Resistors shall be provided with enclosures; and the assembly shall be identified approved [14-142, 14-143] for Class I locations, unless resistance is nonvariable and maximum operating temperature, in degrees Celsius, will not exceed 80 percent of the ignition temperature of the gas or vapor involved, or has been tested and found incapable of igniting the gas or vapor. 501-8. Motors and Generators (a) Class I, Division 1. In Class I, Division 1 locations, motors, generators, and other rotating electric machinery shall be as follows: 1. Identified Approved [14-146,14-147] for Class I, Division 1 locations; or 2. Of the totally enclosed type supplied with positive-pressure ventilation from a source of clean air with discharge to a safe area, so arranged to prevent energizing of the machine until ventilation has been established and the enclosure has been purged with at least 10 volumes of air, and also arranged to automatically deenergize the equipment when the air supply fails; or 3. Of the totally enclosed inert gas-filled type supplied with a suitable reliable source of inert gas for pressuring the enclosure, with devices provided to ensure a positive pressure in the enclosure and arranged to automatically de-energize the equipment when the gas supply fails; or 4. Of a type designed to be submerged in a liquid that is flammable only when vaporized and mixed with air, or in a gas or vapor at a pressure greater than atmospheric and that is flammable only when mixed with air; and the machine is arranged so to prevent

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energizing it until it has been purged with the liquid or gas to exclude air, and also arranged to automatically de-energize the equipment when the supply of liquid or gas or vapor fails or the pressure is reduced to atmospheric. Totally enclosed motors of Types (2) or (3) shall have no external surface with an operating temperature in degrees Celsius in excess of 80 percent of the ignition temperature of the gas or vapor involved. Appropriate devices shall be provided to detect and automatically de-energize the motor or provide an adequate alarm if there is any increase in temperature of the motor beyond designed limits. Auxiliary equipment shall be of a type identified approved [14-144,14-145] for the location in which it is installed. FPN: See ASTM Test Procedure, D 2155-69. (b) Class I, Division 2. In Class I, Division 2 locations, motors, generators, and other rotating electric machinery in which are employed sliding contacts, centrifugal or other types of switching mechanism (including motor overcurrent, overloading, and overtemperature devices), or integral resistance devices, either while starting or while running, shall be identified approved [14149, 14-151] for Class I, Division 1 locations, unless such sliding contacts, switching mechanisms, and resistance devices are provided with enclosures approved for Class I, Division 2 locations in accordance with Section 501-3(b). The exposed surface of space heaters used to prevent condensation of moisture during shutdown periods shall not exceed 80 percent of the ignition temperature in degrees Celsius of the gas or vapor involved when operated at rated voltage, and the maximum surface temperature [based on a 40ºC (104ºF) ambient] shall be permanently marked on a visible nameplate mounted on the motor. Otherwise, space heaters shall be identified approved [14-152] for Class I, Division 2 locations. In Class I, Division 2 locations, the installation of open or nonexplosionproof enclosed motors, such as squirrel-cage induction motors without brushes, switching mechanisms, or similar arc-producing devices that are not identified for use in a Class I, Division 2 location, shall be permitted. FPN No. 1: It is important to consider the temperature of internal and external surfaces that may be exposed to the flammable atmosphere. FPN No. 2: It is important to consider the risk of ignition due to currents arcing across discontinuities and overheating of parts in multisection enclosures of large motors and generators. Such motors and generators may need equipotential bonding jumpers across joints in the enclosure and from enclosure to ground. Where the presence of ignitible gases or vapors is suspected, cleanair purging may be needed immediately prior to and during startup periods. 501-9. Lighting Fixtures Lighting fixtures shall comply with (a) or (b). (a) Class I, Division 1. In Class I, Division 1 locations, lighting fixtures shall comply with the following. (1) Approved Fixtures. Each fixture shall be identified approved as a complete assembly for the Class I, Division 1 location and shall be clearly marked to indicate the maximum wattage of lamps for which it is identified approved . Fixtures intended for portable use shall be specifically identified approved as a complete assembly for that use. [14-153,14-154] (2) Physical Damage. Each fixture shall be protected against physical damage by a suitable guard or by location. (3) Pendant Fixtures. Pendant fixtures shall be suspended by and supplied through threaded rigid metal conduit stems or threaded steel intermediate conduit stems, and threaded joints shall be provided with set-screws or other effective means to prevent loosening. For stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of a fitting or flexible connector identified approved [14-155,14-156] for the Class I, Division 1 location shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting. (4) Supports. Boxes, box assemblies, or fittings used for the support of lighting fixtures shall be identified approved [14-157, 14158] for Class I locations. (b) Class I, Division 2. In Class I, Division 2 locations, lighting fixtures shall comply with the following. (1) Portable Lighting Equipment. Portable lighting equipment shall comply with (a)(1). Exception: Where portable lighting equipment are mounted on movable stands and are connected by flexible cords, as covered in

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Section 501-11, they shall be permitted, where mounted in any position, if they conform to Section 501-9(b)(2). (2) Fixed Lighting. Lighting fixtures for fixed lighting shall be protected from physical damage by suitable guards or by location. Where there is danger that falling sparks or hot metal from lamps or fixtures might ignite localized concentrations of flammable vapors or gases, suitable enclosures or other effective protective means shall be provided. Where lamps are of a size or type that may, under normal operating conditions, reach surface temperatures exceeding 80 percent of the ignition temperature in degrees Celsius of the gas or vapor involved, fixtures shall comply with (a)(1) or shall be of a type that has been tested in order to determine the marked operating temperature or temperature class range (T Code) . (3) Pendant Fixtures. Pendant fixtures shall be suspended by threaded rigid metal conduit stems, threaded steel intermediate metal conduit stems, or by other approved means. For rigid stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of an identified approved [14-162, 14-164] fitting or flexible connector shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting. (4) Switches. Switches that are a part of an assembled fixture or of an individual lampholder shall comply with Section 501-6(b)(1). (5) Starting Equipment. Starting and control equipment for electric-discharge lamps shall comply with Section 501-7(b). Exception: A thermal protector potted into a thermally protected fluorescent lamp ballast if the lighting fixture is identified approved [14-165, 14-166] for locations of this class and division. 501-10. Utilization Equipment (a) Class I, Division 1. In Class I, Division 1 locations, all utilization equipment shall be approved for Class I, Division 1 locations. (b) Class I, Division 2. In Class I, Division 2 locations, all utilization equipment shall comply with the following. (1) Heaters. Electrically heated utilization equipment shall conform with either item (a) or (b). a. The heater shall not exceed 80 percent of the ignition temperature in degrees Celsius of the gas or vapor involved on any surface that is exposed to the gas or vapor when continuously energized at the maximum rated ambient temperature. If a temperature controller is not provided, these conditions shall apply when the heater is operated at 120 percent of rated voltage. Exception No. 1: For motor-mounted anticondensation space heaters, see Section 501-8(b). Exception No. 2: A current-limiting device is applied to the circuit serving the heater that will limit the current in the heater to a value less than that required to raise the heater surface temperature to 80 percent of the ignition temperature. b. The heater shall be identified approved {14-169, 14170] for Class I, Division 1 locations. Exception: Electrical resistance heat tracing identified approved [14-171, 14-172] for Class I, Division 2 locations. (2) Motors. Motors of motor-driven utilization equipment shall comply with Section 501-8(b). (3) Switches, Circuit Breakers, and Fuses. Switches, circuit breakers, and fuses shall comply with Section 501-6(b). 501-11. Flexible Cords, Class I, Divisions 1 and 2 A flexible cord shall be permitted for connection between portable lighting equipment or other portable utilization equipment and the fixed portion of their supply circuit. Flexible cord shall also be permitted for that portion of the circuit where the fixed wiring methods of Section 501-4(a) cannot provide the necessary degree of movement for fixed and mobile electrical utilization equipment, in an industrial establishment where conditions of maintenance and engineering supervision ensure that only qualified persons will install and service the installation, and the flexible cord is protected by location or by a suitable guard from damage. The length of the flexible cord shall be continuous. Where flexible cords are used, the cords shall be as follows:

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1. Of a type listed approved [14-174,14-175] for extra-hard usage; 2. Contain, in addition to the conductors of the circuit, a grounding conductor complying with Section 400-23; 3. Connected to terminals or to supply conductors in an approved manner; 4. Be supported by clamps or by other suitable means in such a manner that there will be no tension on the terminal connections; and 5. Be provided with suitable seals where the flexible cord enters boxes, fittings, or enclosures of the explosionproof type. Exception: As provided in Sections 501-3(b)(6) and 501-4(b). Electric submersible pumps with means for removal without entering the wet-pit shall be considered portable utilization equipment. The extension of the flexible cord within a suitable raceway between the wet-pit and the power source shall be permitted. Electric mixers intended for travel into and out of open-type mixing tanks or vats shall be considered portable utilization equipment. FPN: See Section 501-13 for flexible cords exposed to liquids having a deleterious effect on the conductor insulation. 501-12. Receptacles and Attachment Plugs, Class I, Divisions 1 and 2 Receptacles and attachment plugs shall be of the type providing for connection to the grounding conductor of a flexible cord and shall be identified approved [14-178,14-179] for the location. Exception: As provided in Section 501-3(b)(6). 501-13. Conductor Insulation, Class I, Divisions 1 and 2 Where condensed vapors or liquids may collect on, or come in contact with, the insulation on conductors, such insulation shall be of a type approved for use under such conditions; or the insulation shall be protected by a sheath of lead or by other approved means. 501-14. Signaling, Alarm, Remote-Control, and Communications Systems (a) Class I, Division 1. In Class I, Division 1 locations, all apparatus and equipment of signaling, alarm, remote-control, and communications systems, regardless of voltage, shall be identified approved [14-184,14-185] for Class I, Division 1 locations, and all wiring shall comply with Sections 501-4(a) and 501-5(a) and (c). (b) Class I, Division 2. In Class I, Division 2 locations, signaling, alarm, remote-control, and communications systems shall comply with the following. (1) Contacts. Switches, circuit breakers, and make-and-break contacts of pushbuttons, relays, alarm bells, and horns shall have enclosures identified approved [14-186,14-187] for Class I, Division 1 locations in accordance with Section 501-3(a). Exception: General-purpose enclosures shall be permitted if current-interrupting contacts are one of the following: a. Immersed in oil, or b. Enclosed within a chamber hermetically sealed against the entrance of gases or vapors, or c. In nonincendive circuits, or d. Part of a listed nonincendive component (2) Resistors and Similar Equipment. Resistors, resistance devices, thermionic tubes, rectifiers, and similar equipment shall comply with Section 501-3(b)(2). (3) Protectors. Enclosures shall be provided for lightning protective devices and for fuses. Such enclosures shall be permitted to be of the general-purpose type. (4) Wiring and Sealing. All wiring shall comply with Sections 5014(b) and 501-5(b) and (c). 501-15. Live Parts, Class I, Divisions 1 and 2 There shall be no exposed live parts. 501-16. Grounding, Class I, Divisions 1 and 2 Wiring and equipment in Class I, Division 1 and 2 locations shall be grounded as specified in Article 250 and with the following additional requirements. (a) Bonding. The locknut-bushing and double-locknut types of contacts shall not be depended on for bonding purposes, but bonding jumpers with proper fittings or other approved means of bonding shall be used. Such means of bonding shall apply to all intervening raceways, fittings, boxes, enclosures, etc., between Class I locations and the point of grounding for service equipment or point of grounding of a separately derived system. Exception: The specific bonding means shall only be required to the nearest point where the grounded circuit conductor and the grounding electrode are connected together on the line side of the building or structure disconnecting means as specified in Sections

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250-32(a), (b), and (c), provided the branch-circuit overcurrent protection is located on the load side of the disconnecting means. FPN: See Section 250-100 for additional bonding requirements in hazardous (classified) locations. (b) Types of Equipment Grounding Conductors. Where flexible metal conduit or liquidtight flexible metal conduit is used as permitted in Section 501-4(b) and is to be relied on to complete a sole equipment grounding path, it shall be installed with internal or external bonding jumpers in parallel with each conduit and complying with Section 250-102. Exception: In Class I, Division 2 locations, the bonding jumper shall be permitted to be deleted where all the following conditions are met. a. Listed liquidtight flexible metal conduit 6 ft (1.83 m) or less in length, with fittings listed for grounding, is used. b. Overcurrent protection in the circuit is limited to 10 amperes or less. c. The load is not a power utilization load. 501-17. Surge Protection (a) Class I, Division 1. Surge arresters, including their installation and connection, shall comply with Article 280. The surge arresters and capacitors shall be installed in enclosures identified approved [ 14-194, 14-195] for Class I, Division 1 locations. Surge-protective capacitors shall be of a type designed for specific duty. (b) Class I, Division 2. Surge arresters shall be nonarcing, such as metal-oxide varistor (MOV), sealed type, and surge-protective capacitors shall be of a type designed for specific duty. Installation and connection shall comply with Article 280. Enclosures shall be permitted to be of the general-purpose type. Surge protection of types other than described above shall be installed in enclosures identified approved [14-196,14-197] for Class I, Division 1 locations.

501-18. Multiwire Branch Circuits In a Class I, Division 1 location, a multiwire branch circuit shall not be permitted. Exception: Where the disconnect device(s) for the circuit opens all ungrounded conductors of the multiwire circuit simultaneously. ___________________ (Log #1398) 14- 60 - (501-1): Reject SUBMITTER: Jon Miller, Richard Poling, Detector Electronics Corp./Rep. Detector Electronics Corp./ E I du Pont RECOMMENDATION: Revise 501-1 to read as follows: 501-1. General The general rules of this Code shall apply to the electric wiring and equipment in locations classified as Class I in Section 500-7. Equipment listed and marked in accordance with Section 505-10 for use in Class I, Zone 0, 1, or 2 locations shall be permitted in Class I, Division 2 locations for the same gas and with a suitable temperature rating. Exception: As modified by this article. Permanently mounted combustible gas detection equipment may be used as a means for reducing the need for special electrical equipment when: - combustible gas detection equipment is listed and marked both as performance tested and as suitable for use in hazardous (classified) locations, - combustible gas detection equipment is installed in accordance with industrial practices, - used in industrial establishments where the conditions of maintenance and supervision ensure that only qualified persons will service the installation, and - appropriate alarms with ventilation or interlocks are provided. FPN 1: For suggested minimum performance specifications and guidance in the selection of gas detection equipment, see ISA S12.13.01, Performance Requirements, Combustible Gas Detectors. FPN 2: For suggested installation, operation and maintenance guidance, see ISA RP12.13.02, Installation, Operation, and Maintenance of Combustible Gas Detection Instruments. FPN 3: For guidance in the installation of gas detection equipment, see ANSI/API RP 500, Recommended Practice for

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Classification of Electrical Installations at Petroleum Facilities Classified as Class I, Division 1 and Division 2. SUBSTANTIATION: Equipment necessary to be placed in hazardous (classified) locations which cannot meet specific hazardous location protection techniques currently requires purged/pressurized protection techniques. This is not always possible or desirable under all installation considerations. For many years gas detection equipment has been used as a method of protection in petroleum facilities in accordance with ANSI/API RP 500, Recommended practice for Classification of Electrical Installations at Petroleum Facilities Classified as Class I, Division 1 and Division 2 and within hazardous location facilities in Canada in accordance with the Canadian Electrical Code (CEC) with no reported incidents. Gas detection equipment is capable of providing indication of the presence of combustible gases prior to reaching lower explosive limits and is capable of providing alarms with ventilation or interlocks. To ensure proper gas detection equipment functionality under such critical conditions, an existing ISA standard S12.13.01, Performance Requirements, Combustible Gas Detectors, will provide guidance on gas detection equipment performance requirements and an existing ISA recommended practice RP12.13.02, Installation, Operation, and Maintenance of Combustible Gas Detection Instruments, will provide user guidance on the proper use of gas detection equipment. In conclusion, this additional method of protection should be considered for equipment which cannot meet the proper hazardous (classified) location requirements, but is necessary to be installed in such locations. PANEL ACTION: Reject. PANEL STATEMENT: While the Panel agrees with the principle of selectively applying gas detection in Class I areas, the evaluation process that is required to support this complex operating condition extends beyond merely a simple installation requirement. The NEC is primarily an electrical installation document. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #2613) 14- 61 - (501-2(a)(1)): Accept in Part SUBMITTER: Donald R. Cook, Southern Section, IAEI RECOMMENDATION: Revise text to read as follows: (1) Containing Liquid that Will Burn. Transformers and capacitors containing liquid that will burn shall be installed only in approved (identified) vaults that comply with Sections 450-41 through 450-48, and, in addition, SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. Delete the word "approved" but do not substitute "identified." PANEL STATEMENT: Transformer vaults are not normally identified. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3471) 14- 62 - (501-2(a)(1)): Accept in Part SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: "(1) Containing Liquid that Will Burn. Transformers and capacitors containing liquid that will burn shall be installed only in approved (identified) vaults that comply with Sections 450-41 through 450-48, and, in addition,"

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SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. Delete the word "approved" but do not substitute "identified." PANEL STATEMENT: Transformer vaults are not normally identified. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1553) 14- 63 - (501-3(a)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (a) Class I, Division 1. In Class I, Division 1 locations, meters, instruments, and relays, including kilowatt-hour-meters, instrument transformers, resistors, rectifiers, and thermionic tubes, shall be provided with enclosures approved (identified) for Class I, Division 1 locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: Changing the word "approved" will change the context of the paragraph. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: I do not agree with the Panel Action which is inconsistent with others that involve enclosures in Class I areas, see Proposals 14-130, 131, 132, 133, 136, 137, 140, 141, 142, 143, etc. This equipment could not be "approved" (acceptable to an authority having jurisdiction) without some kind of identification. ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1554) 14- 64 - (501-3(a)): Accept in Part SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise paragraph two to read as follows: Enclosures approved (identified) for Class I, Division 1 locations include explosion-proof enclosures and purged and pressurized enclosures. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. Delete the word "approved", but do not insert the word "identified". PANEL STATEMENT: Panel 14 believes that "approved" does not amplify a statement of fact. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban

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EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3472) 14- 65 - (501-3(a)): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (a) Class I, Division 1. In Class I, Division 1 locations, meters, instruments, and relays, including kilowatt-hour meters, instrument transformers, resistors, rectifiers, and thermionic tubes, shall be provided with enclosures approved (identified) for Class I, Division 1 locations." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: Changing the word "approved" will change the context of the paragraph. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: See my Explanation of Negative Vote on Proposal 14-63. ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3473) 14- 66 - (501-3(a)): Accept in Part SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the second paragraph to read as follows: "Enclosures approved (identified) for Class I, Division 1 locations include explosionproof enclosures and purged and pressurized enclosures." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. Delete the word "approved", but do not insert the word "identified". PANEL STATEMENT: The Panel believes that the word "approved" does not amplify a statement of fact. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1555) 14- 67 - (501-3(b)(1)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (1) Contacts. Switches, circuit breakers, and make- and -break contacts of pushbuttons, relays, alarm bells, and horns shall have enclosures approved (identified) for Class I, Division 1 locations in accordance with Section 501-3(a). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based

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on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Listed enclosures are regularly available. Also, field approval is difficult. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: WECHSLER: According to my notes, when the committee reviewed this specific section, we agreed that in Section 501-3(a) the word "approved" could be deleted because it was extraneous and we edited the text accordingly. However, Section 501-3(b)(1) refers back to Section 501-3(a) and we agreed that we needed "approved." ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3474) 14- 68 - (501-3(b)(1)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (1) Contacts. Switches, circuit breakers, and make-and-break contacts of pushbuttons, relays, alarm bells, and horns shall have enclosures approved (identified) for Class I, Division 1 locations in accordance with Section 501-3(a). SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change the word "approved" to "listed". PANEL STATEMENT: Listed enclosures are regularly available. Also, field approval is difficult. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: WECHSLER: According to my notes, when the committee reviewed this specific section, we agreed that in Section 501-3(a) the word "approved" could be deleted because it was extraneous and we edited the text accordingly. However, Section 501-3(b)(1) refers back to Section 501-3(a) and we agreed that we needed "approved." ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1556) 14- 69 - (501-3(b)(4)): Accept in Principle in Part SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise third sentence to read as follows: Alternatively, approved (identified) equipment shall be permitted to be marked to indicate the temperature range for which it is suitable, using the identification numbers of the Table 500-5(d). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle in Part. Revise 501-3(b)(4) to read: "Alternatively, equipment shall be permitted to be marked to indicate the temperature class for which it is suitable, using Table 500-5(d)." PANEL STATEMENT: Editorial changes have been made to conform to the NEC Style Manual and to conform to changes made in Proposal 14-59a (CP1411). NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION:

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AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3475) 14- 70 - (501-3(b)(4)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the third sentence to read as follows: "Alternatively, approved (identified) equipment shall be permitted to be marked to indicate the temperature range for which it is suitable, using the identification numbers of Table 5005(d)." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: This proposal is identical to Proposal 1469. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1557) 14- 71 - (501-3(b)(6)(3)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (3) The power-supply cord does not exceed 3 ft (914 mm), is of a type approved (identified) for extra-hard usage or for hard usage if protected by location, and is supplied through an attachment plug and receptacle of the locking and grounding type; and.... SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed extra-hard and hard usage cord is readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: WECHSLER: The panel substantiation does not truly justify the action to change the wording. The submitter has not shown that a problem exits, and the fact that a listed product may be more readily available, does not mean that one was "approved" would not provide equal protection or service. Flexible cords should not be considered the same as fittings, and reducers. Under the proposed rewording, flexible cords should more appropriately be "identified." ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________

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(Log #3476) 14- 72 - (501-3(b)(6)(3)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: "(3) The power-supply cord does not exceed 3 ft (914 mm), is of a type approved (identified) for extra-hard usage or for hard usage if protected by location, and is supplied through an attachment plug and receptacle of the locking and grounding type: and". SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed extra-hard and hard usage cord is readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: WECHSLER: See my Explanation of Negative Vote on Proposal 14-71. ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #2125) 14- 73 - (501-4): Accept in Principle in Part Note: The Technical Correlating Committee directs that the Panel clarify the Panel Action on this Proposal. The Panel's stated action is to revise 501-4 as shown in Proposal 14-318a which is a complete rewrite of Article 505, not Article 501. This action will be considered by the Panel as a Public Comment. It was the action of the Technical Correlating Committee that this Proposal be referred to Code-Making Panel 16 for information, with respect to Code-Making Panel 16's Panel Action on Proposal 16-319. CodeMaking Panel 14 shall retain jurisdiction regarding types of wiring methods permitted in hazardous locations. SUBMITTER: Kari Barrett, Chemical Manufacturers Assn. RECOMMENDATION: Revise and add the underlined text into existing paragraph as follows: See NEC Proposal 501-4 Wiring Methods, "Proposal" for the revised rewrite of this entire section. 501-4. Wiring Methods. Wiring methods shall comply with (a) and (b). (a) Class I, Division 1. In Class I, Division 1 locations, apply the following: (1) Threaded rigid metal conduit, or threaded steel intermediate metal conduit may be used. Exception No. 1: Rigid nonmetallic conduit complying with Article 347 shall be permitted where encased in a concrete envelope a minimum of 2 in. (50.8 mm) thick and provided with not less than 24 in. (610 mm) of cover measured from the top of the conduit to grade. The concrete encasement shall be permitted to be omitted where subject to the provisions of Section 511-4, Exception 514-8, Exception No. 2; and Section 515-5(a). Where rigid nonmetallic conduit is used, threaded rigid metal conduit or threaded steel intermediate metal conduit shall be used for the last 24 in. (610 mm) of the underground run to emergence or to the point of connection to the aboveground raceway. An equipment grounding conductor shall be included to provide for electrical continuity of the raceway system and for grounding of noncurrent-carrying metal parts. (2) Type MI cable with termination fittings approved for the location may be used. Type MI cable shall be installed and supported in a manner to avoid tensile stress at the termination fittings. Exception No. 12: In industrial establishments with restricted public access, where the conditions of maintenance and supervision ensure that only qualified persons will service the installation, Type MC cable, listed for use in Class I, Division 1 locations, with a gas/vaportight continuous corrugated aluminum sheath, an overall jacket of suitable polymeric material, separate grounding conductors in accordance with Section 250-122, and provided with termination fittings listed for the application shall be permitted. FPN: See Sections 334-3 and 334-4 for restrictions on use of Type

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MC cable. Exception No. 23: In industrial establishments with restricted public access, where the conditions of maintenance and supervision ensure that only qualified persons will service the installation, Type ITC cable, listed for use in Class I, Division 1 locations, with a gas/vaportight continuous corrugated aluminum sheath, an overall jacket of suitable polymeric material and provided with termination fittings listed for the application shall be permitted. (3) All boxes, fittings, and joints shall be threaded for connection to conduit or cable terminations and shall be explosionproof. Threaded joints shall be made up with at least five threads fully engaged. (4) Flexible Connections. Where necessary to employ flexible connections, as at motor terminals, flexible fittings listed for Class I locations shall be used. Exception: Flexible cord installed in accordance with the provisions of Section 501-11 shall be permitted. (b) Class I, Division 2. In Class I, Division 2 locations, apply the following: (1) Threaded rigid metal conduit, threaded steel intermediate metal conduit, (2) Enclosed gasketed busways, enclosed gasketed wireways, (3) Type PLTC cable in accordance with the provisions of Article 725, or in cable tray systems. PLTC shall be installed in a manner to avoid tensile stress at the termination fittings, (4) Type ITC cable in cable trays, in raceways, supported by messenger wire, afforded mechanical protection and run as open wiring, or directly buried where the cable is listed for this use, (5) Types MI, MC, MV, or TC cable with approved termination fittings, or in cable tray systems and installed in a manner to avoid tensile stress at the termination fittings, (6) Types CATVP, CATVR, CATV, or CATVX in cable tray, and in opening wiring, (7) Where provision must be made for limited flexibility, as at motor terminals, flexible metal fittings, flexible metal conduit with approved fittings, liquidtight flexible metal conduit with approved fittings, liquidtight flexible nonmetallic conduit with approved fittings, or flexible cord approved for extra-hard usage and provided with approved bushed fittings shall be used. An additional conductor for grounding shall be included in the flexible cord, FPN: See Section 501-16(b) for grounding requirements where flexible conduit is used. (8) Boxes, fittings, and joints shall not be required to be explosionproof except as required by Sections 501-3(b)(1), 5016(b)(1), and 501-14(b)(1). SUBSTANTIATION: See NEC Proposal 501-4 Wiring Methods "Problem". · This proposal first reorganizes the existing text within to clarify the requirements, and to correct years of additions that simply aggravated the problem further. For example, the phrase, "Type MI, MC, MV, or TC cable with approved termination fittings shall be the wiring method employed" hardly fits into a paragraph that permits may different installation techniques to be used. · This proposal also eliminates the unnecessary and undefined term "Fixed Wiring" that appeared in 501-4(a)(1) and "Flexible Connections" that appeared in 501-4(a)(2), with a simply listing of permitted methods. · The order of the exceptions under 501-4(a)(1) has been changed to reflect the reordered listing and to agree with the paragraph that the exception applies. · Type CATVP, CATVR, CATV, or CATVX coaxial cables, as described in Article 820-51, have been added as these cables are needed in modern industrial facilities for digital and video signal transmission. Further these cables have the additional having fireresistant characteristics similar to the requirements for other types of cables such as TC and ITC, which are currently permitted for Class I, Division 2 locations. In addition they are suitable for installation in cable trays as permitted by Article 318. PANEL ACTION: Accept in Principle in Part. Revise 501-4 as shown in Proposal 14-318a, but do not accept the addition of Types CATVP, CATVR, CATV, or CATVX in cable tray. PANEL STATEMENT: The submitter has not provided adequate technical justification to support the proposal to accept CATV cable. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE:

Copyright 2000, NFPA

LAWRENCE: Panel action should have been "Accept in Part in Principle" with the removal of Type CATVX and the addition of support/protection requirements to correlate with the actions of Panel 16 on Proposal 16-318 to accept Types CATVP, CATVR, and CATV in Section 820-53(e). COMMENT ON AFFIRMATIVE: WECHSLER: Panel 16 took action to permit the use of all but CATVX in hazardous locations. [See CMP 16, Proposal 16-319] Based upon this action, CMP 14 should have accepted in part, too, the use of coaxial cable to complement the action of CMP 16: "Revise the submitter's proposal by adding a new 820-53(e) as follows: "(e) Hazardous (Classified) Locations. Where the use of Type CATVP, CATVR, and CATV cable is permitted in Section 5014(b), 502-4(b), and 504-20, the cable shall be installed in cable trays; in raceways; supported by messenger wire, or otherwise adequately supported and mechanically protected by angles, struts, channels, or by other mechanical means." ___________________ (Log #2282) 14- 74 - (501-4 Exception No. 4): Reject SUBMITTER: Jack Bartlett, Gilbarco Inc. RECOMMENDATION: Text change for 501-4 as follows: Exception No. 4: In Gas Pumps and Dispensers with restricted public access to the enclosures (i.e., locked cabinets), where the conditions of maintenance and supervision ensure that only qualified persons will install and service the installation, flexible cord of a type suitable to comply with 501-11 and 501-13 will be permitted. SUBSTANTIATION: Flexible cord has been permitted for use in this application outside the USA for many years with no detrimental effect to safety. The continuance of NFPA 70 to demand conduit has a negative effect on USA based design and manufacturing companies to compete in the world market and restricts imaginative design solutions in this market area. PANEL ACTION: Reject. PANEL STATEMENT: Flexible cord is not an acceptable wiring method for permanently installed equipment where there is no demonstarted need. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1558) 14- 75 - (501-4(a)(1)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (1) Fixed Wiring. In Class I, Division 1 locations, threaded rigid metal conduit, threaded steel intermediate metal conduit, or Type MI cable with termination fittings approved (identified) for the location shall be the wiring method employed. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________

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(Log #1811) 14- 76 - (501-4(a)(1)): Reject SUBMITTER: William G. Lawrence, Jr., S. Yarmouth, MA RECOMMENDATION: (Existing Text) ....Threaded joints shall be made up with at least five threads fully engaged..... (Revised Text) ...Threaded joints shall be made up with at least three and one half threads fully engaged.... SUBSTANTIATION: Although the nominal thread engagement of male conduit / female equipment NPT parts threaded per ANSI/ASME B1.20.1 (Pipe Threads, General Purpose Inch) is 5.5 threads, with both the male and female parts at a minimum tolerance (L1-1), the resulting thread engagement is only 3.5 threads. To allow for the five thread engagement currently specified, the female parts have historically been tapped deeper with a minimum limit of L1+0.5. This creates a nominal engagement of 7 threads with a minimum of 5. The International Standard for Type of Protection "d" (IEC 600791) is changing the minimum thread engagement for taper threaded joints from 5 to 3.5 to allow the use of standard NPT gauging practice. Based on flame propagation tests conducted by the British on this construction and the current allowance of a straightthread conduit coupling with a taper-thread conduit, the relaxation from 5 to 3.5 does not represent a compromise in safety. In addition, the introduction of various types of cable glands and other fittings with a hex "shoulder" for tightening aggravates the problem. With the male NPT thread on the fitting conforming to the standard ASME gauging and the female equipment entry tapped deeper to ensure five threads of engagement, it is highly likely that the shoulder will contact the surface of the equipment before the NPT threads are "tight" resulting in a "loose" joint likely to propagate an explosion. The Europeans recognized this potential problem several years ago and the "European ATEX Notified Bodies Group ExNB" issue Clarification Sheet ExNB/98/06/010/CS requiring that, for Eurpean Certification, female threaded entries conform to ANSI/ASME B1.20.1 and also meet the five thread engagement. This results in female entries tapped to L1+0.5 / L1+1 instead of the deeper L1+0.5 / L1+3.5. This tight tolerance with a half thread "window" in lieu of a 3 thread "window" makes manufacturing difficult with much scrap produce The change in NPT thread engagement does not compromise safety and would allow US manufacturers to produce one product for use both here in the US and in the rest of the world. PANEL ACTION: Reject. PANEL STATEMENT: The submitter has not demonstrated that relaxation of this requirement will not detract from the integrity of the installation. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: LAWRENCE: The panel statement ignores the statement by the submitter that "straight thread" couplings have been permitted to be used with "tapered thread" conduit since the 1930's. This already permitted joint results in a thread engagement relaxation far greater than that proposed for "taper-thread" to "taper-thread" joints. ___________________ (Log #3477) 14- 77 - (501-4(a)(1)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (1) Fixed Wiring. In Class I, Division 1 locations, threaded rigid metal conduit, threaded steel intermediate metal conduit, or Type MI cable with termination fittings approved (identified) for the location shall be the wiring method employed. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION:

Copyright 2000, NFPA

AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #2998) 14- 78 - (501-4(a)(1) Exception No. 2): Accept Note: The Technical Correlating Committee understands that the Proposal reference in the Panel Statement is to Proposal 14-59a. SUBMITTER: Michael P. Mennone, Rockbestos-Surprenant Cable Corp. RECOMMENDATION: Revise Section 501-4(a)(1) Exception No. 2 to read as follows: Exception No. 2: In industrial establishments with restricted public access, where the conditions of maintenance and supervision ensure that only qualified persons will service the installation, Type MC cable, listed for use in Class I, Division 1 locations, with a gas/vaportight continuous corrugated aluminum metallic sheath, an overall jacket of suitable polymeric material, separate grounding conductors in accordance with Section 250-122, and provided with termination fittings listed for the application shall be permitted. SUBSTANTIATION: Type MC with a gas/vaportight continuous corrugated sheath is manufactured and listed with various (aluminum, stainless steel, copper) sheath materials. In response to the acceptance of this exception (which was to be added to the 1996 NEC), UL Standard No. 2225 entitled "Metal-Clad Cables and Cable-Sealing Fittings for Use in Hazardous (Classified) Locations" was developed to qualify Type MC cables for this specific use. Cables meeting these additional requirements would then be listed as Type MC-HL. Copper and stainless steel sheathed Type MC cables have the same ability as aluminum to meet the intent of this section and also possess the ability to meet all of the additional requirements stated in UL Standard No. 2225. It is our contention that these additional types of sheathed cables were overlooked in the original proposal. This capability does exist and should be recognized by the code. PANEL ACTION: Accept. PANEL STATEMENT: The accepted change is reflected in Proposal 14-318a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1559) 14- 79 - (501-4(b)): Accept in Part SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (b) Class I, Division 2. In Class I, Division 2 locations, threaded rigid metal conduit, threaded steel intermediate metal conduit, enclosed gasketed busways, enclosed gasketed wireways, or Type PLTC cable in accordance with the provisions of Article 725, or Type ITC cable in cable trays, in raceways, supported by messenger wire, or directly buried where the cable is listed for this use; Type MI, MC, MV, or TC cable with approved (identified) termination fittings shall be the wiring method employed. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. Delete the word "approved". PANEL STATEMENT: Requirements for ordinary location electrical equipment need not be repeated in Chapter 5. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban

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EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #1560) 14- 80 - (501-4(b)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise fourth sentence to read as follows: Where provision must be made for limited flexibility, as at motor terminals, flexible metal fittings, flexible metal conduit with approved (identified) fittings, liquidtight flexible metal conduit with approved (identified) fittings, liquidtight flexible nonmetallic conduit with approved (identified) fittings, or flexible cord approved (identified) for extra-hard usage and provided with approved (identified) bushed fittings shall be used. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-87 is identical and addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #2127) 14- 81 - (501-4(b)): Accept in Principle in Part Note: The Technical Correlating Committee understands that the Proposal reference in the Panel Statement is to Proposal 14-59a. SUBMITTER: Kari Barrett, Chemical Manufacturers Assn. RECOMMENDATION: Delete the current exception "Exception: Nonincendive field wiring shall be permitted using any of the methods suitable for wiring in ordinary locations" and replace it with the following positive text: "Nonincendive field wiring shall be permitted using any of the wiring methods suitable for unclassified locations, including Chapter 7 and Chapter 8 methods, and special instrument cables. At termination boxes and instruments, coaxial and multiconductor cables may be run as open wiring for up to 6 ft to allow flexibility for limited movement, vibrations, or replacement." SUBSTANTIATION: In accordance with the NEC Style Manual, since nonincendive field wiring is a defined term, it is not appropriate to consider this an exception. It is a recognized practice and the revised text, provides this fact with revised wording that permits any wiring method to be used for this special type of field wiring. PANEL ACTION: Accept in Principle in Part. Add the following to 501-4(b): "(4) Nonincendive field wiring shall be permitted using any of the wiring methods permitted for nonhazardous locations, including Chapter 7 and 8 wiring methods." PANEL STATEMENT: This change is reflected in Proposal 14318a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________

Copyright 2000, NFPA

(Log #2295) 14- 82 - (501-4(b)): Reject SUBMITTER: Gregory J. Steinman, Thomas & Betts Corp. RECOMMENDATION: Revise the fourth sentence to read as follows: "Where provision must be made for limited flexibility , or where flexibility is needed for installation, as at motor terminals, flexible metal fittings, flexible metal conduit with approved fittings, liquidtight flexible nonmetallic conduit with approved fittings, or flexible cord approved for extra hard usage and provided with approved bushed fittings shall be used." SUBSTANTIATION: Mast arm type pole mounted luminaires need a flexible wiring method to pull through the mast arm. If these wiring methods are suitable to be flexible in Class I Division 2 locations, they should be suitable enclosed within a pole. This is an application where flexibility is not needed for the use of the product, only in the installation. PANEL ACTION: Reject. PANEL STATEMENT: "Needed" is a reduction in the requirements based on "must" in the referenced sentence. If required for installation, this method is allowed already. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #2530) 14- 83 - (501-4(b)): Accept in Principle in Part Note: The Technical Correlating Committee understands that the Proposal reference in the Panel Statement is to Proposal 14-59a. SUBMITTER: Nicholas Ludlam, Factory Mutual Research RECOMMENDATION: (b) Class I, Division 2. In Class I, Division 2 locations, threaded rigid metal conduit, threaded steel intermediate metal conduit, enclosed gasketed busways, enclosed gasketed wireways, or Type PLTC cable in accordance with the provisions of Article 725, or Type ITC cable in cable trays, in raceways, supported by messenger wire, or directly buried where the cable is listed for this use; Type MI, MC, MV, or TC cable with approved termination fittings shall be the wiring method employed. Type ITC, PLTC, MI, MC, MV, or TC cable shall be permitted to be installed in cable tray systems and shall be installed in a manner to avoid tensile stress at the termination fittings. Boxes, fittings, and joints shall not be required to be explosionproof except as required by Sections 501-3(b)(1), 501-6(b)(1), and 501-14(b)(1). Where provision must be made for limited flexibility, as at motor terminals, flexible metal fittings, flexible metal conduit with approved fittings, liquidtight flexible metal FPN: See Section 501-16(b) for grounding requirements where flexible conduit is used. Exception: Nonincendive field wiring shall be permitted using any of the methods suitable for wiring in unclassified locations. Nonincendive field wiring apparatus, associated nonincendive field wiring apparatus, and other equipment shall be installed in accordance with the control drawing(s). FPN: The control drawing identification is marked on the apparatus. Exception: A simple apparatus that does not interconnect nonincendive field wiring circuits. SUBSTANTIATION: 501-4 is modified to require a Control Drawing which details the permitted connections. PANEL ACTION: Accept in Principle in Part. Add the following new sentence to 501-4(b): "Nonincendive field wiring systems shall be installed in accordance with the control drawing(s)." This change is reflected in Proposal 14-318a. PANEL STATEMENT: The concept of the control drawings has been accepted and editorially revised. The Fine Print Note is not accepted because it includes a requirement and an exception. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________

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(Log #2850) 14- 84 - (501-4(b)): Reject SUBMITTER: Nicholas Ludlam, Factory Mutual Research RECOMMENDATION: Separation of Nonincendive Field Wiring Conductors (a) From Nonincendive Field Wiring Conductors. (1) Open Wiring. Conductors and cables of nonincendive field wiring circuits not in raceways or cable trays shall be separated at least 1.97 in. (50 mm) and secured from conductors and cables of any other circuits. (2) In Raceways, Cable Trays, and Cables. Conductors of nonincendive field wiring circuits shall not be placed in any raceway, cable tray, or cable with conductors of any other circuit. Exception No. 1: Where conductors of nonincendive field wiring circuits are separated from conductors of incendive field wiring circuits by a distance of at least 1.97 in. (50 mm) and secured, or by a grounded metal partition or an approved insulating partition. FPN: No. 20 gauge sheet metal partitions 0.0359 in. (912 µm) or thicker are generally considered acceptable. Exception No. 2: Where either (1) all of the nonincendive field wiring circuit conductors or (2) all of the incendive field wiring circuit conductors are in grounded metal-sheathed or metal-clad cables where the sheathing or cladding is capable of carrying fault current to ground. FPN: Cables meeting the requirements of Articles 330 and 334 are typical of those considered acceptable. (3) Within Enclosures. a. Conductors of nonincendive field wiring circuits shall be separated at least 1.97 in. (50 mm) from conductors of any incendive field wiring circuits, or as specified in Section 5014(b)(a)(2). b. All conductors shall be secured so that any conductor that might come loose from a terminal cannot come in contact with another terminal. FPN No. 1: The use of separate wiring compartments for the nonincendive field wiring and incendive field wiring terminals is the preferred method of complying with this requirement. FPN No. 2: Physical barriers such as grounded metal partitions or approved insulating partitions or approved restricted access wiring ducts separated from other such ducts by at least in. (19 mm) can be used to help ensure the required separation of the wiring. (b) From Different Nonincendive Field Wiring Circuit Conductors. Different nonincendive field wiring circuits shall be in separate cables or shall be separated from each other by one of the following means. 1. The conductors of each circuit are within a grounded metal shield. 2. The conductors of each circuit have insulation with a minimum thickness of 0.01 in. (254 µm). Exception: Unless otherwise approved. SUBSTANTIATION: Apart from the exception in 501-4(b) the current version of the Code does not give any guidance on wiring for nonincendive field wiring circuits. An examination of nonincendive field wiring takes into consideration the faults of opening, shorting, and grounding of the field wiring. When applied to multiple conductor applications such as programmable logic controllers [PLCs] this type of approach can lead to output parameters for the devices which render them unusable. The current version of the Code requires the examination to include situations which, cannot be determined by the manufacturer of the equipment or an NRTL. The installer could determine these parameters but how many would actually consider these in the case where multiple nonincendive circuits are run in a single cable. The situation is similar to that for intrinsically safe wiring, and the proposed text is based on that in Article 504-30. PANEL ACTION: Reject. PANEL STATEMENT: The Panel believes that there is no technical justification given for separatiion of conductors above what is required in nonhazardous locations. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________

Copyright 2000, NFPA

(Log #2934) 14- 85 - (501-4(b)): Reject SUBMITTER: Richard J. Buschart, PC & E Inc. RECOMMENDATION: In the first paragraph, after the words "steel intermediate conduit", add "rigid nonmetallic conduit with an equipment grounding conduction". SUBSTANTIATION: Addition of rigid nonmetallic conduit to Class I, Division 2 wiring methods. This proposal provides the option of using a conduit system that is corrosion resistant and safe for Class I, Division 2 locations. Chemical plants, refineries, off shore drilling facilities, and other similar processes are highly corrosive and also have classified areas. Nonmetallic conduit provides a critical option in these locations. The NEC requirements for rigid nonmetallic conduit are found in Article 347. Rigid nonmetallic conduit is also listed in the UL Information Directory, which describes the types of rigid nonmetallic conduit, and also in UL Standard 1684. Rigid nonmetallic conduit is permitted in Class III, Division I locations as a buried raceway in Class I locations in Commercial Garages, Article 511; in Bulk Storage Plants, Articles 515; and in Class I, Division I locations when enclosed in concrete. This proposal also requires an equipment grounding conduction in these locations. Rigid nonmetallic conduit is not permitted where subject to physical damage unless identified for such use. PANEL ACTION: Reject. PANEL STATEMENT: There is insufficient technical information presented to accept this proposal. There are concerns about mechanical strength and the proposal is not specific enough about the product that is desired to be used. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3478) 14- 86 - (501-4(b)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (b) Class I, Division 2. In Class I, Division 2 locations, threaded rigid metal conduit, threaded steel intermediate metal conduit, enclosed gasketed busways, enclosed gasketed wireways, or Type PLTC cable in accordance with the provisions of Articles 725, or Type ITC cable in cable trays, in raceways, supported by messenger wire, or directly buried where the cable is listed for this use: Type MI. MC, MV, or TC cable with approved (identified) termination fittings shall be the wiring method employed. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Delete the word "approved". PANEL STATEMENT: Requirements for ordinary location electrical equipment need not be repeated in Chapter 5. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3479) 14- 87 - (501-4(b)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the fourth sentence to read as follows: "Where provision must be made for limited flexibility, as at motor terminals, flexible metal fittings, flexible metal conduit with approved (identified) fittings, liquidtight flexible metal conduit with approved (identified) fittings, liquidtight flexible nonmetallic conduit with approved (identified) fittings, or flexible cord approved (identified) for extra-hard usage and provided with approved (identified) bushed fittings shall be used."

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SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change the word "approved" to "listed" in all cases. PANEL STATEMENT: Listed equipment is readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #4236) 14- 88 - (501-4(b), Exception): Accept in Principle Note: The Technical Correlating Committee understands that the Proposal reference in the Panel Statement is to Proposal 14-59a. SUBMITTER: Frederic P. Hartwell, Hartwell Electrical Services, Inc. RECOMMENDATION: Revise by deleting the word "ordinary" and replacing it with the word "unclassified." SUBSTANTIATION: This is the technically correct term. This was proposal 14-113 in the prior cycle, one of four proposals that the panel accepted in the ROP, forgot about, and inadvertently wiped out through unrelated editorial activity in the comment period. PANEL ACTION: Accept in Principle. See Proposal 14-318a. PANEL STATEMENT: Proposal 14-318a addresses this issue. The word "nonhazardous" has been established by definition in Proposal 14-2a and meets the submitter's intent. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: The panel action should be "Accept". See my comments on Proposal 14-2a. GOODMAN: This proposal should be "Accept" and not "Accept in Principle". The Panel Action is contrary to the submitter's intent and justification. The correct term is "unclassified". Also see detailed comment under Proposal 14-2a. Note that the reference used in the Panel Action and Panel Statement of Proposal 14-318a applies to the Article 505 rewrite and does not apply to this proposal or action. ___________________ (Log #1561) 14- 89 - (501-5): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise second sentence to read as follows: Sealing compound shall be of a type approved (identified) for the conditions and use. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Delete the second sentence in 501-5. PANEL STATEMENT: The Panel believes its action on Proposal 14-104 meets the intent of the submitter. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban

Copyright 2000, NFPA

EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3032) 14- 90 - (501-5): Accept in Principle SUBMITTER: Sukanta Sengupta, FMC Corp. RECOMMENDATION: Revise the second line to read as follows: Sealing compound shall be of a type tested and approved for the conditions and use on specific brand of fittings as integral installation. SUBSTANTIATION: Sealing compound is tested on specific brand fittings and is approved only for that brand of fittings. A mix match of seal fittings and sealing compound of various brands is a common problem of installation practice. This revision is required for avoiding faulty installations. PANEL ACTION: Accept in Principle. See Proposal 14-89. PANEL STATEMENT: Proposal 14-89 addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3480) 14- 91 - (501-5): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the second sentence to read as follows: "Sealing compound shall be of a type approved (identified) for the conditions and use." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-89 addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3481) 14- 92 - (501-5(a)(1), Exception (c)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise Exception (c) to read as follows: (c) Enclosed within a factory-sealed explosionproof chamber located within the enclosure, approved (identified) for the location, and marked "factory sealed" or equivalent. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________

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(Log #1969) 14- 93 - (501-5(a)(1), Exception (c)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise as follows: (c) Enclosed within a factory-sealed explosion-proof chamber located within the enclosure, approved (identified) for the location, and marked "factory sealed" or equivalent. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #4237) 14- 94 - (501-5(a)(1), Exception (d)): Accept SUBMITTER: Frederic P. Hartwell, Hartwell Electrical Services, Inc. RECOMMENDATION: Add a part (d) as a fourth option under the Exception, as follows: d. In nonincendive circuits. SUBSTANTIATION: The operational language of the parent language under exception specifically mentions ignition sources in "normal" operation. A nonincendive circuit is presumed to not be ignition capable under normal operating conditions. Therefore, this proposal doesn't increase the risk of ignition, and it increases the flexibility of the wiring system design. Although this substantiation is my own, the proposal was Proposal 14-121 in the prior cycle. It is one of four proposals that the panel accepted in the ROP, forgot about, and inadvertently wiped out through unrelated editorial activity in the comment period. PANEL ACTION: Accept. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1562) 14- 95 - (501-5(a)(4)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise third sentence to read as follows: Except for approved (identified) explosionproof reducers at the conduit seal; there shall be no union, coupling, box, or fitting between the conduit seal and the point at which the conduit leaves the Division 1 location. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed reducers are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban

Copyright 2000, NFPA

EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3482) 14- 96 - (501-5(a)(4)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text of sentence three to read as follows: "Except for approved (identified) explosionproof reducers at the conduit seal, there shall be no union, coupling, box or fitting between the conduit seal and the point at which the conduit leaves the Division 1 location." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed reducers are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3307) 14- 97 - (501-5(a)(4) Exception No. 2): Reject SUBMITTER: Shawn K. Williams, B.H.M.G. Consulting Engineers RECOMMENDATION: Add a new exception to read as follows: Exception No. 2: Where a submerged pump is installed in a sewage wet well that has been classified as a Class I Division 1 location and has flexible cords for connection to a supply or control circuit as allowed in 501-11, a junction box with terminals listed for Class I locations may be installed between the boundary of the classified location and the seal fitting required by 5015(a)(4) to facilitate easy removal of the pump cable. SUBSTANTIATION: The code as it is written now requires that the pump cable be installed in a seal fitting. If the pump needs to be removed for maintenance the seal fitting must be destroyed, possibly damaging the cable, in order to remove the pump cable. An explosionproof junction box will allow for easy removal of the cable and provide a safe installation in case gases build up and arcing occurs in the junction box. PANEL ACTION: Reject. PANEL STATEMENT: It is not permitted to have a box between the boundary and a seal fitting. This situation may be already covered by 501-11. The submitter's intent is not clear. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________

(Log #4238) 14- 98 - (501-5(a)(4) Exception No. 2): Accept SUBMITTER: Frederic P. Hartwell, Hartwell Electrical Services, Inc. RECOMMENDATION: Identify the existing exception as Exception No. 1 and add a second exception as follows: Exception No. 2: For underground conduit installed in accordance with Section 300-5 where the boundary is beneath the ground, the sealing fitting shall be permitted to be installed after the conduit leaves the ground, but there shall be no union, coupling, box, or fitting, other than approved explosionproof reducers at the sealing fitting, in the conduit between the sealing fitting and the point at which the conduit leaves the ground.

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SUBSTANTIATION: Section 501-5(c)(1) requires seals to be accessible. Since hazardous locations frequently involve flammable gases and vapors heavier than air, generally area classifications require graded locations below a classified location to retain the same area classification. Some Code rule expressly impose this requirement, such as Section 515-6, which mandates a Division 1 classification for below grade conduits. The only way to literally combine these two rules is to go through the burden of installing a handhole within a conduit length of the transition point. This proposal is a reasonable compromise to address this problem. Its principle is reflected in Sec. 514-8, which has allowed this procedure since the 1987 NEC through the verbal sleight of hand of artificially extending the boundary of the classified location. I am submitting a companion proposal to remove that language from Section 514-8, since it won't be necessary if this general procedure is agreed to. Although this is my own substantiation, the proposal is the final panel action in the ROP on Proposal 14-126 in the previous cycle. It is one of four proposals that the panel accepted in the ROP, forgot about, and in-advertently wiped out through unrelated editorial activity in the comment period. PANEL ACTION: Accept. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #2133) 14- 99 - (501-5(b) Exception No. 1): Reject SUBMITTER: Kari Barrett, Chemical Manufacturers Assn. RECOMMENDATION: Revise text to read as follows: "Metal conduit containing no unions, couplings, boxes or fittings that passes completely through a Class I, Division 2 location with no fittings less than 12 in. (305 mm) beyond each boundary shall not be required to be sealed if the termination points of the unbroken conduit are in unclassified locations. Couplings shall be permitted in the conduit run in the Division 2 location." SUBSTANTIATION: A metal conduit, containing only couplings, completely passing through a Division 2 location and terminating with both ends in an unclassified location should not require sealing. The risk of vapors in ignitable quantities in the atmosphere, migrating into the conduit, which is at the same atmospheric pressure both inside and outside the conduit, through a threaded metal coupling in a Division 2 location is extremely low if not nonexistent. PANEL ACTION: Reject. PANEL STATEMENT: The submitter has not provided sufficient technical justification for reducing the requirements. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: GOODMAN: The current Exception allows a conduit completely passing through a Division 2 location with both ends in an unclassified location to not require seals. The submitter's request to add only couplings into that conduit should be permitted. As indicated in the substantiation, there is, in essence, no risk of the entrance or migration of vapors from the Division 2 location to the unclassified location since there is no differential pressure to "push" into the conduit system any vapors which may be present. ___________________

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would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed reducers are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3483) 14- 101 - (501-5(b)(2)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text of fourth sentence to read as follows: "Except for approved (identified) explosionproof reducers at the conduit seal, there shall be no union, coupling box, or fitting between the conduit seal and the point at which the conduit leaves the Division 2 location." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed reducers are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1564) 14- 102 - (501-5(c)(1)): Accept in Principle in Part SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (1) Fittings. Enclosures for connections or equipment shall be provided with an approved (identified) intergral means for sealing or sealing fittings approved (identified) for Class I locations shall be used. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle in Part. Delete the first "approved" and replace the second "approved" with "listed". PANEL STATEMENT: The first "approved" is redundant. With respect to the second, listed seals are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________

(Log #1563) 14- 100 - (501-5(b)(2)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise fourth sentence to read as follows: Except for approved (identified) explosionproof reducers at the conduit seal; there shall be no union, coupling, box, or fitting between the conduit seal and the point at which the conduit leaves the Division 2 location. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction

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(Log #3484) 14- 103 - (501-5(c)(1)): Accept in Principle in Part SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (1) Fittings. Enclosures for connections or equipment shall be provided with an approved (identified) integral means for sealing, or sealing fittings approved (identified) for Class I locations shall be used. Sealing fittings shall be accessible. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle in Part. PANEL STATEMENT: Proposal 14-102 is identical and addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1565) 14- 104 - (501-5(c)(2)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (2) Compound. Sealing compound shall be approved (identified) and shall provide against passage of gas or vapors through the seal fitting, shall not be affected by the surrounding atmosphere or liquids, and shall have not have a melting point of less that 93°C (200°F). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Revise the last sentence of 501-5(c)(1) to read: "Sealing fittings shall be listed for use with one or more specific compounds and shall be accessible." Revise 501-5(c)(2) to read: "The compound shall provide a seal against passage of gas or vapor through the seal fitting, shall not be affected by the surrounding atmosphere or liquids, and shall not have a melting point of less than 93 deg C (200 deg F)." PANEL STATEMENT: The proposed changes provide additional clarification for the requirements for sealing compound. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3485) 14- 105 - (501-5(c)(2)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (2) Compound. Sealing compound shall be approved (identified) and shall provide a seal against passage of gas or vapors through the seal fitting, shall not be affected by the surrounding atmosphere or liquids, and shall not have a melting point of less than 93°C (200°F). SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based

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on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-104 is identical and addresses the same issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1566) 14- 106 - (501-5(c)(5)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (5) Assemblies. In an assembly where equipment that may produce arc, sparks, or high temperatures is located in a compartment separate from the compartment containing splices or taps, and an integral seal is provided where conductors pass from one compartment to the other, the entire assembly shall be approved (identified) for Class I locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3486) 14- 107 - (501-5(c)(5)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (5) Assemblies. In an assembly where equipment that may produce arcs, sparks, or high temperatures is located in a compartment separate from the compartment containing splices or taps, and an integral seal is provided where conductors pass from one compartment to the other, the entire assembly shall be approved (identified) for Class I locations. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________

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(Log #1567) 14- 108 - (501-5(c)(6)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (6) Conductor Fill. The cross-sectional area of the conductors permitted in a seal shall not exceed 25 percent of the crosssectional area of a rigid metal conduit of the same trade size unless it is specifically approved (identified) for a higher percentage of fill. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3487) 14- 109 - (501-5(c)(6)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (6) Conductor Fill. The cross-sectional area of the conductors permitted in a seal shall not exceed 25 percent of the crosssectional area of a rigid metal conduit of the same trade size unless it is specifically approved (identified) for a higher percentage of fill. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1968) 14- 110 - (501-5(d)(1)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise the third sentence as follows: Multiconductor Type MC cables with a gas/vaportight continuous corrugated aluminum sheath and an overall jacket of suitable polymeric material shall be sealed with an approved (identified) fitting after removing the jacket and any other covering so that the sealing compound will surround each individual insulated conductor in such a manner as to minimize the passage of gases and vapors. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction

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would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3489) 14- 111 - (501-5(d)(1)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the third sentence to read as follows: "Multiconductor Type MC cables with a gas/vaportight continuous corrugated aluminum sheath and an overall jacket of suitable polymeric material shall be sealed with an approved (identified) fitting after removing the jacket and any other covering so that the sealing compound will surround each individual insulated conductor in such a manner as to minimize the passage of gases and vapors." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1967) 14- 112 - (501-5(d)(1), Exception): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise as follows: Exception: Shielded cables and twisted pair cables shall not require the removal of the shielding material or separation of the twisted pairs provided the termination is by an approved (identified) means to minimize the entrance of gases and vapors and prevent propagation of flame into the cable core. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________

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(Log #3488) 14- 113 - (501-5(d)(1), Exception): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the Exception to read as follows: Exception. Shielded cables and twisted pair cables shall not require the removal of the shielding material or separation of the twisted pairs provided the termination is by an approved (identified) means to minimize the entrance of gases or vapors and prevent propagation of flame into the cable core. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1975) 14- 114 - (501-5(d)(2), Exception): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise as follows: Exception: Multiconductor cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall be permitted to be considered as a single conductor by sealing the cable in the conduit within 18 in. (457 mm) of the enclosure and the cable end within the enclosure by an approved (identified) means to minimize the entrance of gases and vapors and prevent propagation of flame into the cable core, or by other approved (identified) methods. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3490) 14- 115 - (501-5(d)(2), Exception): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the Exception to read as follows: Exception. Multiconductor cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall be permitted to be considered as a single conductor by sealing the cable in the conduit within 18 in. (457 mm) of the enclosure and the cable end within the enclosure by an approved (identified) means to minimize the entrance of gases or vapors and prevent the propagation of flame into the cable core, or by other approved (identified) methods. For shielded cables and twisted pair cables, it shall not be required to remove the shielding material or separate the twisted pair. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires

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that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1568) 14- 116 - (501-5(e)(1)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (1) Cables entering enclosures that are required to be approved (identified) for Class I locations shall be sealed at the point of entrance. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Replace "approved for Class I locations" with the word "explosionproof". PANEL STATEMENT: This is consistent with 501(b)(1). NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #1569) 14- 117 - (501-5(e)(1)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise paragraph one, sentence three to read as follows: Multiconductor cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall be sealed in an approved (identified) fitting in the Division 2 location after removing the jacket and any other coverings so that the sealing compound will surround each individual insulated conductor in such a manner as to minimize the passage of gases and vapors. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban

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EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3491) 14- 118 - (501-5(e)(1)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (1) Cables entering enclosures that are required to be approved (identified) for Class I locations shall be sealed at the point of entrance. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: This is identical to Proposal 14-116. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3492) 14- 119 - (501-5(e)(1)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: In paragraph one, revise the third sentence to read as follows: "Mulitconductor cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall be sealed in an approved (identified) fitting in the Division 2 location after removing the jacket and any other coverings so that the sealing compound will surround each individual insulated conductor in such a manner as to minimize the passage of gases or vapors." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1976) 14- 120 - (501-5(e)(1) Exception No. 2): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise as follows: Exception No. 2: Shielded cables and twisted pair cables shall not require the removal of the shielded material or separation of the twisted pairs provided the termination is by an approved (identified) means to minimize the entrance of gases and vapors and prevent propagation of flame into the cable core. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based

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on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3493) 14- 121 - (501-5(e)(1) Exception No. 2): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise Exception No. 2 to read as follows: Exception No. 2: Shielded cables and twisted pair cables shall not require the removal of the shielding material or separation or the twisted pairs provided the termination is by an approved (identified) means to minimize the entrance of gases or vapors and prevent propagation of flame into the cable core. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1570) 14- 122 - (501-5(f)(1)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (1) Control Equipment. Where there is a probability that liquid or other condensed vapor may be trapped within enclosures for control equipment or at any point in the raceway system, approved (identified) means shall be provided to prevent accumulation or to permit periodic draining of such liquid or condensed vapor. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________

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(Log #1985) 14- 123 - (501-5(f)(1), (2), and (3)): Reject SUBMITTER: John H. Rannells, JHR Consulting RECOMMENDATION: Revise text to read as follows: 501-5. Sealing and Drainage. (f) Drainage. (1) Control Equipment. Where there is a probability that liquid or other condensed vapor may enter and be trapped within enclosures for control equipment or at any point in the raceway system, approved means shall be provided to prevent accumulation or to permit periodic draining of such liquid or condensed vapor. FPN No. 1: Electrical Submersible Pump (ESP) produced oil well operate at high pressures and may also experience seal leakage and the attendant problems. FPN No. 2: Other codes or standards may require special handling of the above "trapped liquid or condensed vapor". FPN No. 3: In addition to "liquid or other condensed vapor" poisonous gases such as hydrogen sulfide (H2S) may also be present and "may enter, and be trapped within, enclosures" and parts of the raceway systems. (2) Motors and Generators. Where the authority having jurisdiction judges that there is a probability that liquid or condensed vapor may accumulate within motors or generators, joints and conduit systems shall be arranged to minimize entrance of the liquid. If means to prevent accumulation or to permit periodic draining are judged necessary, such means shall be provided at the time of manufacture and shall be considered an integral part of the machine. (3) Canned Pumps, Process or Service Connections, etc. For canned pumps, process or service connections for flow, pressure, or analysis measurement, etc., that depend on a single compression seal, diaphragm, or tube to prevent flammable or combustible fluids from entering the electrical conduit, raceway or cable system capable of transmitting fluids, an additional listed seal system, seal, barrier, or other means shall be provided to prevent the flammable or combustible fluid from entering the conduit, raceway or cable system capable of transmitting fluids beyond the additional systems, devices or means, if the primary seal fails. The additional approved seal system, seal or barrier and the interconnecting enclosure shall meet the temperature and pressure conditions to which they will be subjected upon failure of the primary seal, unless other approved means are provided to accomplish the purpose above. Drains, vents, or other devices shall be provided so that primary seal leakage will be obvious. FPN: See also the fine print notes to Section 501-5. SUBSTANTIATION: Problem: The problem is that materials not listed for high pressure are installed in systems where they may encounter high-pressure fluids. NEC Article 501-5(f), (1), (2), and (3) works perfectly when the process system is not under high pressure. But, because it requires material not listed for pressure [Rigid Metal Conduit (RMC), Electrical Metallic Tubing (EMT), Drains or Vents, and Poured Conduit Seals], it is possible that "flammable or combustible fluids" may enter "arcing electrical devices" in processes operating at high pressure such as Electrical Submersible Pump (ESP) "produced" oil wells ("5000 psi). - RMC may be derived from ASTM A-53, but is not listed for pressure, and is therefore not suitable for pressure service. - EMT, with a wall thickness less than RMC of the same external diameter, is not listed for pressure and is therefore not suitable for pressure service. - Poured Conduit Seals are not listed for pressures beyond those in 501-5, (e), (2) and are therefore not suitable for use in situations where they are required to prevent the passage of gases at pressures greatly in excess of 6 in. of water (1493 pascals). - Conduit Drains, Vents, and Fittings are not listed for pressure and are therefore not suitable for pressure service. Solution: The use of a listed system (Primary Seal, Drain/Vent, and Secondary Seal) for high process pressure ("5000 psi) applications will eliminate release of flammable or combustible fluids that may occur when conduit, fittings, drains or vents, and seals, not listed for high pressures, are used...and fail. High pressure capable, NRTL listed systems, are available and in use in the United States today. PANEL ACTION: Reject.

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PANEL STATEMENT: The substantiation addresses a pressure rating problem which does not exist in the code. Section 5015(f)(3) requires that seals and barriers meet the pressure requirements to which they might be subjected. There is no substantiation given for the fine print notes. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3335) 14- 124 - (501-5(f)(1)): Reject SUBMITTER: Sukanta Sengupta, FMC Corp. RECOMMENDATION: Revise the title as follows: (1) Control Equipment and Raceway System. SUBSTANTIATION: Editorial revision. Drainage of raceway is a major item in wiring system and it should be highlited. PANEL ACTION: Reject. PANEL STATEMENT: The panel does not believe there is a need to revise the title. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3494) 14- 125 - (501-5(f)(1)): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (1) Control Equipment. Where there is a probability that liquid or other condensed vapor may be trapped within enclosures for control equipment or at any point in the raceway system, approved (identified) means shall be provided to prevent accumulation or to permit periodic draining of such liquid or condensed vapor. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1571) 14- 126 - (501-5(f)(3)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (3) Canned Pumps, Process or Service Connections, etc. For canned pumps, process or service connections for flow, pressure, or analysis measurement, etc., that depend on a single compression seal, diaphragm, or tube to prevent flammable or combustible fluids from entering the electrical raceway or cable system capable or transmitting fluids, an additional approved (identified) seal, barrier, or other means shall be provided to prevent the flammable or combustible fluid from entering the raceway or cable system capable of transmitting fluids beyond the additional devices or means, if the primary falls.

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SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1572) 14- 127 - (501-5(f)(3)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise paragraph two to read as follows: The additional approved (identified) seal or barrier and the interconnecting enclosure shall meet the temperature and pressure conditions to which they will be subjected upon failure of the primary seal, unless other approved (identified) means are provided to accomplish the purpose above. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3495) 14- 128 - (501-5(f)(3)): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (3) Canned Pumps, Process or Service Connections, etc. for canned pumps, process or service connections for flow, pressure, or analysis measurement, etc., that depend on a single compression seal, diaphragm, or tube to prevent flammable or combustible fluids from entering the electrical raceway or cable system capable of transmitting fluids, an additional approved (identified) seal, barrier, or other means shall be provided to prevent the flammable or combustible fluid from entering the raceway or cable system capable of transmitting fluids beyond the additional devices or means, if the primary seal fails. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________

Copyright 2000, NFPA

(Log #3496) 14- 129 - (501-5(f)(3)): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: "The additional approved (identified) seal or barrier and the interconnecting enclosure shall meet the temperature and pressure conditions to which they will be subjected upon failure of the primary seal, unless other approved (identified) means are provided to accomplish the purpose above." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1573) 14- 130 - (501-6(a)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (a) Class I, Division 1. In Class I, Division 1 locations, switches, circuit breakers, motor controllers, and fuses, including pushbuttons, relays, and similar devices, shall be provided with enclosures, and the enclosure in each case, together with the enclosed apparatus, shall be approved (identified) as a complete assembly for use in Class I locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3497) 14- 131 - (501-6(a)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (a) Class I, Division 1. In Class I, Division 1 locations, switches, circuit breakers, motor controllers, and fuses, including pushbuttons, relays, and similar devices, shall be provided with enclosures, and the enclosure in each case, together with the enclosed apparatus, shall be (1) Type Required. Circuit breakers, motor controllers, and switches intended to interrupt current in the normal performance of the function for which they are installed shall be provide with enclosures approved (identified) for Class I, Division 1 locations in accordance with Section 501-3(a), unless general-purpose enclosures are provided and as a complete assembly for use in Class I locations.

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SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1574) 14- 132 - (501-6(b)(1)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: "(1) Type Required. Circuit breakers, motor controllers, and switches intended to interrupt current in the normal performance of the function for which they are installed shall be provided with enclosures approved (identified) for Class 1, Division 1 locations in accordance with Section 501-3(a), unless general-purpose enclosures are provided and...". SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3498) 14- 133 - (501-6(b)(1)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (1) Type Required. Circuit breakers, motor controllers, and switches intended to interrupt current in the normal performance of the function for which they are installed shall be provide with enclosures (1) Type Required. Circuit breakers, motor controllers, and switches intended to interrupt current in the normal performance of the function for which they are installed shall be provide with enclosures approved (identified) for Class I, Division 1 locations in accordance with Section 501-3(a), unless general-purpose enclosures are provided and for Class I, Division 1 locations in accordance with Section 501-3(a), unless generalpurpose enclosures are provided and SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept.

Copyright 2000, NFPA

PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1575) 14- 134 - (501-6(b)(1)c): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (c) The interruption of current occurs within a factory-sealed explosionproof chamber approved (identified) for the location, or.... SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Delete "approved for the location". PANEL STATEMENT: Explosionproof equipment is suitable for the location by nature of its definition. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3499) 14- 135 - (501-6(b)(1)(c)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (c) The interruption of current occurs within a factory-sealed explosionproof chamber approved (identified) for the location, or. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-134 is identical and addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1576) 14- 136 - (501-6(b)(3)): Accept in Part SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (3) Fuses. For the protection of motors, appliances, and lamps, other than as provided in (b)(4), standard plug or cartridge fuses shall be permitted, provided they are placed within enclosures approved (identified) for the location, or fuses shall be permitted

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if they are within general-purpose enclosures, and if they are of a type in which the operating element is immersed in oil or other approved (identified)liquid, or the operating element is enclosed within a chamber hermetically sealed against the entrance of gases, vapors, or the fuse is a nonindicating, filled, current-limiting type. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. Change only first "approved" with "identified". PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. Also, a "liquid" cannot be listed or identified. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: COOK: I will agree that the liquid used to immerse the element of a fuse will not be listed, however I would assume that the fuse manufacturer would identify some specific liquid to be used for that purpose. I would also assume that all liquids would not be acceptable and that an authority having jurisdiction should not be the person determining which liquid is acceptable. I would like to have input from the fuse manufacturers on this issue before determining if "approved" is the correct term. WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3500) 14- 137 - (501-6(b)(3)): Accept in Part SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read: (3) Fuses. For the protection of motors, appliances, and lamps, other than as provided in (b)(4), standard plug or cartridge fuses shall be permitted, provided they are placed within enclosures approved (identified) for the location; or fuses shall be permitted if they are within general-purpose enclosures, and if they are of a type in which the operating element is immersed in oil or other approved (identified) liquid, or the operating element is enclosed within a chamber hermitically sealed against the entrance of gases and vapors, or the fuse is a nonindicating, filled, current-limiting type. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. See Proposal 14-136 PANEL STATEMENT: Proposal 14-136 is identical and addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: COOK: See my Comment on Affirmative on Proposal 14-136. ___________________ (Log #1577) 14- 138 - (501-6(b)(4)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (4) Fuses Internal to Lighting Fixtures. Approved (identified)

Copyright 2000, NFPA

cartridge fuses shall be permitted as supplementary protection within lighting fixtures. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the appropriate word to use here. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 9 NEGATIVE: 3 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: I disagree with the Panel Action and Statement. Fuses that are used for supplementary protection are not an item that an authority having jurisdiction could "approve" (acceptable to the authority having jurisdiction) without some listing or identification. I realize that the listing or identification would not be for hazardous locations, the proposal does not propose fuses identified for hazardous locations, however test lab directories include many listings for ordinary location fuses that are acceptable. I can not imagine any authority having jurisdiction or owner at a hazardous location facility that would want a fuse that did not meet the ordinary location requirements. Listed fuses are readily available. JAGUNICH: The deletion of the word "approved" should be accepted but no word should be substituted for it. CMP14 has repeatedly stated that means or methods must be approved, but has removed the word "approved" for all other purposes within the articles for which the panel is responsible. Code enforcement officials rarely have at their disposal the tools for approving supplementary protection within lighting fixtures. ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3501) 14- 139 - (501-6(b)(4)): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (4) Fuses Internal to Lighting Fixtures. Approved (Identified) cartridge fuses shall be permitted as supplementary protection within lighting fixtures. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the appropriate word to use here. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 9 NEGATIVE: 3 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: See my Explanation of Negative on Proposal 14-138. JAGUNICH: See my Explanation of Negative on Proposal 14-138 (Log #1577). ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1578) 14- 140 - (501-7(a)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (a) Class I, Division 1. In Class I, Division 1 locations, transformers, impedance coils, and resistors, together with any switching mechanism associated with them, shall be provided with enclosures approved (identified) for Class I, Division 1 locations in accordance with Section 501-3(a). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires

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that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3502) 14- 141 - (501-7(a)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (a) Class I, Division 1. In Class I, Division 1 locations, transformers, impedance coils, and resistors, together with any switching mechanism associated with them, shall be provided with enclosures approved (identified) for Class I, Division 1 locations in accordance with Section 501-3(a). SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1579) 14- 142 - (501-7(b)(3)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (3) Resistors. Resistors shall be provided with enclosures; and the assembly shall be approved (identified)for Class I locations, unless resistance is nonvariable and maximum operating temperature, in degrees Celsius, will not exceed 80 percent of the ignition temperature of the gas or vapor involved, or has been tested and found incapable of igniting the gas or vapor. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________

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(Log #3503) 14- 143 - (501-7(b)(3)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (3) Resistors. Resistors shall be provided with enclosures; and the assembly shall be approved (identified) for Class I locations, unless resistance is nonvariable and maximum operating temperature, in degrees Celsius, will not exceed 80 percent of the ignition temperature of the gas or vapor involved, or has been tested and found incapable of igniting the gas or vapor. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1963) 14- 144 - (501-8(a)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise the second paragraph, third sentence as follows: Auxilliary equipment shall be of a type approved (identified) for the location in which it is installed. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3505) 14- 145 - (501-8(a)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: In the second paragraph, revise the third sentence to read as follows: "Auxiliary equipment shall be of a type approved (identified) for the location in which it is installed." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept.

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PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1580) 14- 146 - (501-8(a)(1)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (1) Approved (identified) for Class I, Division 1 locations; or.... SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3504) 14- 147 - (501-8(a)(1)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (1) Approved (Identified) for Class I, Division 1 locations; or. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3306) 14- 148 - (501-8(a)(4)): Reject SUBMITTER: Shawn K. Williams, B.H.M.G. Consulting Engineers RECOMMENDATION: Revise as follows: Of a type designed to be submerged in a liquid that is flammable only when vaporized and mixed with air, or in a gas or vapor at a pressure greater than atmospheric. SUBSTANTIATION: This portion of the code is not logical. Why allow a pump to be nonexplosion proof if submerged in a flammable liquid but require a pump that is submerged in a nonflammable liquid such as water to be explosionproof. The

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same deenergizing requirements listed later in the paragraph will work for both applications. PANEL ACTION: Reject. PANEL STATEMENT: The substantiation does not support the proposal. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1581) 14- 149 - (501-8(b)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (b) Class I, Division 2. In Class I, Division 2 locations, motors, generators, and other rotating electric machinery in which are employed sliding contacts, centrifugal or other types of switching mechanism (including motor overcurrent, overloading and overtemperature devices), or integral resistance devices, either while starting or while running, shall be approved (identified) for Class I, Division 1 locations, unless such sliding contacts, switching mechanisms, and resistance devices are provided with enclosures approved (identified) for Class I, Division 2 locations in accordance with Section 501-3(b). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #1582) 14- 150 - (501-8(b)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise first paragraph, third sentence to read as follows: Otherwise, space heaters shall be approved (identified) for Class I, Division 2 locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________

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(Log #3506) 14- 151 - (501-8(b)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (b) Class I, Division 2. In Class I, Division 2 locations, motors, generators, and other rotating electric machinery in which are employed sliding contacts, centrifugal or other types of switching mechanism (including motor overcurrent, overloading, and overtemperature devices), or integral resistance devices, either while starting or while running, shall be approved (identified) for Class I, Division 1 locations, unless such sliding contacts, switching mechanisms, and resistance devices are provided with enclosures approved (identified) for Class I, Division 2 locations in accordance with Section 501-3(b). SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3507) 14- 152 - (501-8(b)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: In the first paragraph, revise the third sentence to read as follows: "Otherwise, space heaters shall be approved (identified) for Class I, Division 2 locations." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1583) 14- 153 - (501-9(a)(1)): Accept Note: It was the action of the Technical Correlating Committee that the Panel give consideration to also revising the title of 5019(a)(1) to correlate with the Panel's actions on Proposals 14-237 and 14-238. This action will be considered by the Panel as a Public Comment. SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (1) Approved Fixtures. Each fixture shall be approved (identified) as a complete assembly for the Class I, Division 1 location and shall be clearly marked to indicate the maximum wattage of lamps for which it is approved (identified). Fixtures intended for portable use shall be specifically approved (identified ) as a complete assembly for that use. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based

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on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3508) 14- 154 - (501-9(a)(1)): Accept Note: It was the action of the Technical Correlating Committee that the Panel give consideration to also revising the title of 5019(a)(1) to correlate with the Panel's actions on Proposals 14-237 and 14-238. This action will be considered by the Panel as a Public Comment. SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (1) Approved Fixtures. Each fixture shall be approved (identified) as a complete assembly for the Class I, Division 1 location and shall be clearly marked to indicate the maximum wattage of lamps for which it is approved (identified). Fixtures intended for portable use shall be specifically approved (identified) as a complete assembly for that use. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1584) 14- 155 - (501-9(a)(3)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise second sentence to read as follows: For stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of a fitting or flexible connector approved (identified) for the Class I, Division 1 location shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14

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VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3509) 14- 156 - (501-9(a)(3)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the second sentence to read as follows: "For stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of a fitting or flexible connector approved (identified) for the Class I, Division 1 location shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1585) 14- 157 - (501-9(a)(4)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (4) Supports. Boxes, box assemblies, or fittings used for the support of lighting fixtures shall be approved (identified) for Class I locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________

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(Log #3510) 14- 158 - (501-9(a)(4)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (4) Supports. Boxes, box assemblies, or fittings used for the support of lighting fixtures shall be approved (identified) for Class I locations. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3804) 14- 159 - (501-9(b)(2)): Reject SUBMITTER: Hector R. de Vega, Fluor Daniel, Inc. RECOMMENDATION: Revise text to read as follows: (2) Fixed Lighting. Lighting fixtures for fixed lighting shall be protected from physical damage by suitable guards or by location. Where there is danger that falling sparks or hot metal from lamps or fixtures might ignite localized concentrations of flammable vapors or gases, suitable enclosures or other effective means shall be provided. Where lamps are of a size or type that may, under normal operating conditions, reach surface temperatures exceeding 80 percent of the ignition temperature in degrees Celsius of the gas or vapor involved, fixtures shall comply with (a)(1) above or shall be of a type that has been tested in order to determine the marked operating temperature or temperature range not to exceed 100 percent of the ignition temperature in degrees Celsius of the gas or vapor involved. SUBSTANTIATION: The original text allowed a fixture to be used in a Class I, Division 2 area without regard to the maximum surface temperature of the fixture, provided it was "tested and marked". This proposal would limit the use of "tested and marked" fixtures to those that do not exceed 100 percent of the ignition temperature of the surrounding atmosphere. PANEL ACTION: Reject. PANEL STATEMENT: The concern of the submitter is already covered by 500-5(e) of the existing code. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #4414) 14- 160 - (501-9(b)(2)): Reject SUBMITTER: Stephen V. Norako, Cooper Crouse-Hinds Div. RECOMMENDATION: Revise text to read as follows: "Where lamps are of a size or type that may, under normal operating conditions, reach surface temperatures exceeding 80 percent of the ignition temperatures in degrees Celsius of the gas or vapor involved, fixtures shall with (a)(1) or shall be of a type that has been tested in order to determine the marked operating temperature or temperature range." SUBSTANTIATION: Lamp temperatures today are seldom if ever published by the lamp manufacturers. When temperatures are available, they are established in open air at favorable ambient (25°C). These temperature values in no way compare to the temperatures reached inside enclosed thick walled glass light fixtures at the high ambiance, 40°C or higher, typical of industrial establishments. Therefore this 80 percent rule has no basis and should be deleted. PANEL ACTION: Reject.

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PANEL STATEMENT: The substantiation does not demonstrate the possibility that lamp temperatures will reach or exceed autoignition temperatures. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: I disagree with the Panel Action and agree with the submitter's proposal and substantiation. It is also an unenforceable requirement. ___________________ (Log #1586) 14- 161 - (501-9(b)(3)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (3) Pendant Fixtures. Pendant fixtures shall be suspended by threaded rigid metal conduit stems, threaded steel intermediate metal conduit stems, or by other approved (identified) means. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1587) 14- 162 - (501-9(b)(3)): Accept Note: The Technical Correlating Committee understands that the Proposal revises the second sentence of the section. SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: For rigid stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of an approved (identified) fitting or flexible connector shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________

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(Log #3511) 14- 163 - (501-9(b)(3)): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (3) Pendant Fixtures. Pendant Fixtures shall be suspended by threaded rigid metal conduit stems, threaded steel intermediate metal conduit stems, or by other approved (identified) means. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3512) 14- 164 - (501-9(b)(3)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the second sentence to read as follows: "For rigid stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of an approved (identified) fitting or flexible connector shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1962) 14- 165 - (501-9(b)(5), Exception): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise as follows: Exception: A thermal protector potted into a thermally protected fluorescent lamp ballast if the lighting fixture is approved (identified) for locations of this class and division. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION:

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AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ Log #3513) 14- 166 - (501-9(b)(5), Exception): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the Exception to read as follows: Exception: A thermal protector potted into a thermally protected fluorescent lamp ballast if the lighting fixture is approved (identified) for locations of this class and division. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1588) 14- 167 - (501-10(a)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (a) Class I, Division 2. In Class I, Division 2 locations, all utilization equipment shall be approved (identified) for Class I, Division 1 locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: The wording of the recommended text was incorrectly copied from 501-10(a). The intent is covered by Proposal 14-168. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3514) 14- 168 - (501-10(a)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (a) Class I, Division 1. In Class I, Division 1 locations, all utilization equipment shall be approved (identified) for Class I, Division 1 locations. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept.

Copyright 2000, NFPA

PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1589) 14- 169 - (501-10(b)(1)b): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (b) The heater shall be approved (identified) for Class I, Division 1 locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3515) 14- 170 - (501-10(b)(1)b): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (b) The heater shall be approved (identified) for Class I, Division 1 locations. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1961) 14- 171 - (501-10(b)(1)b, Exception): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise as follows: Exception: Electrical resistance heat tracing approved (identified) for Class I, Division 2 locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based

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on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3516) 14- 172 - (501-10(b)(1)b, Exception): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the Exception to read as follows: Exception: Electrical resistance heat tracing approved (identified) for Class I, Division 2 locations. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3987) 14- 173 - (501-11): Accept in Principle Note: It was the action of the Technical Correlating Committee that this Proposal be reconsidered and correlated with the action on Proposal 14-318a. The Technical Correlating Committee understands that there is no change to 501-11. This action will be considered by the Panel as a Public Comment. SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL RECOMMENDATION: Revise text to read as follows: 501-11. 505-17. Flexible Cords, Class I, Divisions Zones 1 and 2. A flexible cord shall be permitted for connection between portable lighting equipment or other portable utilization equipment and the fixed portion of their supply circuit. Flexible cord shall also be permitted for that portion of the circuit where the fixed wiring methods of Section 501-4(a) 505-15(b) cannot provide the necessary degree of movement for fixed and mobile electrical utilization equipment, in an industrial establishment where conditions of maintenance and engineering supervision ensure that only qualified persons will install and service the installation, and the flexible cord is protected by location or by a suitable guard from damage. The length of the flexible cord shall be continuous. Where flexible cords are used, the cords shall be as follows: 1. Of a type approved for extra-hard usage; 2. Contain, in addition to the conductors of the circuit, a grounding conductor complying with Section 400-23; 3. Connected to terminals or to supply conductors in an approved manner; 4. Be supported by clamps or by other suitable means in such a manner that there will be no tension no the terminal connections; and 5. Be provided with suitable seals where the flexible cord enters boxes, fittings, or enclosures that are required to be explosionproof or flameproof. Exception: As provided in Sections 501-3(b)(6) and 501-4(b).

Copyright 2000, NFPA

505-15(c). Electric submersible pumps with means for removal without entering the wet-pit shall be considered portable utilization equipment. The extension of the flexible cord within a suitable raceway between the wet-pit and the power source shall be permitted. Electric mixers intended for travel into and out of open-type mixing tanks or vats shall be considered portable utilization equipment. FPN: See Section 501-13 505-18 for flexible cords exposed to liquids having a deleterious effect on the conductor insulation. SUBSTANTIATION: This proposal is the work of a Task Group including Ed Briesch, Bill Lawrence, Dave Wechsler, Lon Ballard, Larry Fuhrman, and Will McBride. This Task Group was not balloted. The purpose of the proposal is to provide clear guidelines for wiring, sealing, and installation in Article 505, without having to refer to Article 501. PANEL ACTION: Accept in Principle. Add the following as new 505-17: "505-17. Flexible Cords, Class I, Zones 1 and 2. A flexible cord shall be permitted for connection between portable lighting equipment or other portable utilization equipment and the fixed portion of their supply circuit. Flexible cord shall also be permitted for that portion of the circuit where the fixed wiring methods of Section 505-15(b) cannot provide the necessary degree of movement for fixed and mobile electrical utilization equipment, in an industrial establishment where conditions of maintenance and engineering supervision ensure that only qualified persons will install and service the installation, and the flexible cord is protected by location or by a suitable guard from damage. The length of the flexible cord shall be continuous. Where flexible cords are used, the cords shall be as follows: 1. Of a type listed for extra-hard usage; 2. Contain, in addition to the conductors of the circuit, a grounding conductor complying with Section 400-23; 3. Connected to terminals or to supply conductors in an approved manner; 4. Be supported by clamps or by other suitable means in such a manner that there will be no tension no the terminal connections; and 5. Be provided with listed seals where the flexible cord enters boxes, fittings, or enclosures that are required to be explosionproof or flameproof . Exception: As provided in Sections 505-15(c)(2). Electric submersible pumps with means for removal without entering the wet-pit shall be considered portable utilization equipment. The extension of the flexible cord within a suitable raceway between the wet-pit and the power source shall be permitted. Electric mixers intended for travel into and out of open-type mixing tanks or vats shall be considered portable utilization equipment. FPN: See Section 505-18 for flexible cords exposed to liquids having a deleterious effect on the conductor insulation." PANEL STATEMENT: The panel has changed the words "approved" and "suitable" to "listed" in accordance with present requirements in Article 505. Cross-references have also been corrected where necessary. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #1590) 14- 174 - (501-11(1)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (1) Of a type approved (identified) for extra-hard usage. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle.

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Change "approved" to "listed". PANEL STATEMENT: Listed extra-hard and hard usage cord is readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: WECHSLER: See my Explanation of Negative Vote on Proposal 14-71. ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #4483) 14- 175 - (501-11(1)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: "(1) Of a type approved (identified) for extra-hard usage;" SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed extra-hard and hard usage cord is readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: WECHSLER: See my Explanation of Negative Vote on Proposal 14-71. ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1591) 14- 176 - (501-11(3)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (3) Connected to terminals or to supply conductors in approved (identified) manner. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #4484) 14- 177 - (501-11(3)): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (3) Connected to terminals or to supply conductors in an approved (identified) manner: SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose.

Copyright 2000, NFPA

PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1592) 14- 178 - (501-12): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: 501-12. Receptacles and Attachment Plugs, Class I, Divisions 1 and 2. Receptacles and attachment plugs shall be of the type providing for connection to the grounding conductor of a flexible cord and shall be approved (identified) for the location. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #4485) 14- 179 - (501-12): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: 501-12. Receptacles and Attachment Plugs, Class I, Divisions 1 and 2. Receptacles and attachment plugs shall be of the type providing for connection to the grounding conductor of a flexible cord and shall be approved (identified) for the location. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1593) 14- 180 - (501-13): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: 501-13. Conductor Insulation, Class I, Divisions 1 and 2. Where condensed vapors or liquids may collect on, or come in contact

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with, the insulation on conductors, such insulation shall be of a type approved (identified) for use under such conditions; or the insulation shall be protected by a sheath of lead or by other approved (identified) means. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: To accept this proposal would cause a conflict with the action taken on Proposal 14-181. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: I disagree with the Panel Action. I have no idea how an authority having jurisdiction could "approve" conductor insulation for use in chemical atmospheres. We do not expect the authority having jurisdiction to determine suitability of insulation, for use in wet locations without the insulation being identified with a "W", but expect the same authority having jurisdiction to determine if the insulation is suitable to be used in chemical atmospheres. After reviewing the test criteria for gasoline and oil resistance ratings, I am certain that I am not qualified to make those approvals in the field without some way to identify that the insulation is suitable. ___________________ (Log #3989) 14- 181 - (501-13): Accept in Principle Note: It was the action of the Technical Correlating Committee that this Proposal be reconsidered and correlated with the action on Proposal 14-318a. The Technical Correlating Committee understands that there is no change to 501-13. This action will be considered by the Panel as a Public Comment. SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL RECOMMENDATION: Revise text to read as follows: 501-13. 505-18. Conductor Insulation, Class I, Divisions Zones 1 and 2. Where condensed vapors or liquids may collect on, or come in contact with, the insulation on conductors, such insulation shall be of a type approved for use under such conditions; or the insulation shall be protected by a sheath of lead or by other approved means. SUBSTANTIATION: This proposal is the work of a Task Group including Ed Briesch, Bill Lawrence, Dave Wechsler, Lon Ballard, Larry Fuhrman, and Will McBride. This Task Group was not balloted. The purpose of the proposal is to provide clear guidelines for wiring, sealing, and installation in Article 505, without having to refer to Article 501. PANEL ACTION: Accept in Principle. Add a new 505-18 to read: "Conductors and Conductor Insulation. (1) For Type of Protection 'e', field wiring conductors shall be copper. (2) Where condensed vapors or liquids may collect on, or come in contact with, the insulation on conductors, such insulation shall be of a type approved for use under such conditions; or the insulation shall be protected by a sheath of lead or by other approved means." PANEL STATEMENT: This text is placed in the correct location as originally intended and redundant references have been deleted. The similar requirement in 501-13 will remain. The requirement in (1) is taken from Section 4.1 of ISA S12.16.011998 (IEC 79-7 Mod) titled Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations Type of Protection ­ Increased Safety "e". See Proposal 14-365 for additional information. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban COMMENT ON AFFIRMATIVE: COOK: I agree with the Panel Action with a comment to see Proposal 14-180 for use of the term "approved". WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________

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(Log #4486) 14- 182 - (501-13): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: 501-13. Conductor Insulation, Class I, Divisions 1 and 2. Where condensed vapors or liquids may collect on, or come in contact with, the insulation on conductors, such insulation shall be of a type approved (identified) for use under such conditions; or the insulation shall be protected by a sheath of lead or by other approved (identified) means. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: To accept this proposal would cause a conflict with the action taken on Proposal 14-181. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: See my Explanation of Negative on Proposal 14-180. ___________________ (Log #920) 14- 183 - (501-13(a)): Reject SUBMITTER: Dan Leaf, Palmdale, CA RECOMMENDATION: Revise to read as follows: (a) Power Supply. Power supply to contact conductors shall be ungrounded and electrically isolated from all other systems and... (remainder unchanged). SUBSTANTIATION: Editorial. Article 100 definition of isolated does not seem appropriate. Proposal clearly states what appears to be the intent. There is no specific requirement for an ungrounded power supply in this section; one has to refer to Section 250-22 for specificity as to what is intended. PANEL ACTION: Reject. PANEL STATEMENT: There is no 501-13(a) to revise. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1594) 14- 184 - (501-14(a)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (a) Class I, Division 1. In Class I, Division 1 locations, all apparatus and equipment of signaling, alarm, remote-control, and communications systems, regardless of voltage, shall be approved (identified) for Class I, Division Ilocations, and all wiring shall comply with Sections 501-4(a) and 501-5(a) and (c). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban

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EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3517) 14- 185 - (501-14(a)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (a) Class I, Division 1. In Class I, Division 1 locations, all apparatus and equipment of signaling, alarm, remote-control, and communications systems, regardless of voltage, shall be approved (identified) for Class I, Division 1 locations, and all wiring shall comply with Sections 501-4(a) and 501-5(a) and (c). SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1595) 14- 186 - (501-14(b)(1)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (1) Contacts. Switches, circuit breakers, and make-and-break contacts of pushbuttons, relays, alarm bells, and horns shall have enclosures approved (identified)for Class I, Division 1 locations in accordance with Section 501-3(a). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3518) 14- 187 - (501-14(b)(1)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (1) Contacts. Switches, circuit breakers, and make-and-break contacts of pushbuttons, relays, alarm bells, and horns shall have enclosures approved (identified) for Class I, Division 1 locations in accordance with Section 501-3(a). SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based

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on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3985) 14- 188 - (501-15): Accept in Principle Note: It was the action of the Technical Correlating Committee that this Proposal be reconsidered and correlated with the action on Proposal 14-318a. The Technical Correlating Committee understands that there is no change to 501-15. This action will be considered by the Panel as a Public Comment. SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL RECOMMENDATION: Revise text to read as follows: 501-15. 505-19. Live Parts, Class I, Divisions Zones 1 and 2. There shall be no exposed live parts. SUBSTANTIATION: This proposal is the work of a Task Group including Ed Briesch, Bill Lawrence, Dave Wechsler, Lon Ballard, Larry Fuhrman, and Will McBride. This Task Group was not balloted. The purpose of the proposal is to provide clear guidelines for wiring, sealing, and installation in Article 505, without having to refer to Article 501. PANEL ACTION: Accept in Principle. Revise to read as follows: "505-19 Live Parts. There shall be no exposed live parts." PANEL STATEMENT: This makes Article 505 consistent with Article 501. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #589) 14- 189 - (501-16, 502-16): Reject SUBMITTER: Ted Abner, Pinckney, MI RECOMMENDATION: I propose the below listed sections make reference back to other like sections where possible due to the fact the only difference between them is their classifications. Section 501-16 Grounding, Class I, Division 1 and 2. Wiring and equipment in Class I and II Division 1 and 2 locations shall be grounded as specified in Article 250 and with the following additional requirements: (a) Bonding. The locknut-bushing and double-locknut types of contacts shall not be depended upon for bonding purposes, but bonding jumpers with proper fittings or other approved means of bonding shall be used. Such means of bonding shall apply to all intervening raceways, fittings, boxes, enclosures, etc., between Class I or II locations and the point of grounding for service equipment or point of grounding of a separately derived system. Section 502-16. Grounding, Class II, Division 1 and 2. Shall comply with Section 501-16. Wiring and equipment in Class II Division 1 and 2 locations shall be grounded as specified in Article 250 and with the following additional requirements: (a) Bonding. The locknut-bushing and double locknut types of contacts shall not be depended upon for bonding purposes, but bonding jumpers with proper fittings or other approved means of bonding shall be used. Such mans of bonding shall apply to all intervening raceways, fittings, boxes, enclosures, etc., between Class II locations and the point of grounding for service equipment or point of grounding of a separately derived system. The above listed article is only one of many changes that could be made throughout the code.

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SUBSTANTIATION: This proposal would eliminate duplication of paragraphs. PANEL ACTION: Reject. PANEL STATEMENT: The Panel's intent is to keep Class I and Class II requirements separate. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1596) 14- 190 - (501-16(a)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (a) Bonding. The locknut-bushing and double-locknut types of contacts shall not be depended on for bonding purposes, but bonding jumpers with proper fittings or other approved (identified)means of bonding shall be used. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #2385) 14- 191 - (501-16(a)): Reject Note: It was the action of the Technical Correlating Committee that this Proposal be referred to Code-Making Panel 5 for information. SUBMITTER: William E. Bickner, Stillwater, MN RECOMMENDATION: Revise as shown below: (a) Bonding. Standard locknuts or bushings The locknutbushing, and double-locknut types of contacts shall not be depended on for bonding purposes, but bonding jumpers with proper fittings or other approved means of bonding shall be used; bonding shall comply with Sections 250-100 and 250-94. (Balance of paragraph and exception unchanged) FPN: See Section 250-100 for additional bonding requirements in hazardous (classified) locations. SUBSTANTIATION: Present wording conflicts with Section 25094, which is referenced by Section 250-100. Taken literally, it does not require bonding for standard locknuts that are employed to secure threadless connectors to enclosures, nor around concentric or eccentric knockouts that may not be suitable for bonding, as required under Section 250-94. May also be interpreted to prohibit the use of bonding locknuts and bushings, which are acceptable under Section 250-94. (The balance of this paragraph and the exception are also unnecessary if submitter's proposal for Section 250-100 is accepted). PANEL ACTION: Reject. PANEL STATEMENT: These requirements are more stringent than those in Article 250. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: I disagree with the Panel Action and Statement. I agree with the submitter's proposal and most of the substantiation. I am not certain about the last sentence, in parentheses, since I have not seen the submitter's proposal for Section 250-100. ___________________

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(Log #2386) 14- 192 - (501-16(a)): Reject SUBMITTER: William E. Bickner, Stillwater, MN RECOMMENDATION: Revise as shown below: (a) Bonding. Standard locknuts or bushings The locknutbushing, and double-locknut types of contacts shall not be depended on for bonding purposes, but bonding jumpers with proper fittings or other approved means of bonding shall be used; bonding shall comply with Sections 250-100 and 250-94. (Balance of paragraph and exception unchanged) FPN: See Section 250-100 for additional bonding requirements in hazardous (classified) locations. SUBSTANTIATION: Present wording conflicts with Section 25094, which is referenced by Section 250-100. Taken literally, it does not require bonding for standard locknuts that are employed to secure threadless connectors to enclosures, nor around concentric or eccentric knockouts that may not be suitable for bonding, as required under Section 250-94. May also be interpreted to prohibit the use of bonding locknuts and bushings, which are acceptable under Section 250-94. PANEL ACTION: Reject. PANEL STATEMENT: These requirements are more stringent than those in Article 250. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: See my Explanation of Negative Vote on Proposal 14-191. ___________________ (Log #3519) 14- 193 - (501-16(a)): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (a) Bonding. The locknut-bushing and double-locknut types of contacts shall not be depended on for bonding purposes, but bonding jumpers with proper fittings or other approved (identified) means of bonding shall be used. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1597) 14- 194 - (501-17(a)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (a) Class I, Division 1. Surge arresters, including their installation and connection, shall comply with Article 280. The surge arresters and capacitors shall be installed in enclosures approved (identified)for Class I, Division 1 locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION:

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AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3520) 14- 195 - (501-17(a)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (a) Class I, Division 1. Surge arresters, including their installation and connection, shall comply with Article 280. The surge arresters and capacitors shall be installed in enclosures approved (identified) for Class I, Division 1 locations. Surgeprotective capacitors shall be of a type designed for specific duty. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1598) 14- 196 - (501-17(b)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise second paragraph to read as follows: Enclosures shall be permitted to be of the general-purpose type. Surge protection of types other than described above shall be installed in enclosures approved (identified) for Class I, Division 1 locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3521) 14- 197 - (501-17(b)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the second paragraph to read as follows: "Enclosures shall be permitted to be of the general-purpose type.

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Surge protection of types other than described above shall be installed in enclosures approved (identified) for Class I, Division 1 locations." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3988) 14- 198 - (501-18): Accept in Principle Note: It was the action of the Technical Correlating Committee that this Proposal be reconsidered and correlated with the action on Proposal 14-318a. The Technical Correlating Committee understands that there is no change to 501-18. This action will be considered by the Panel as a Public Comment. SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL RECOMMENDATION: Revise text to read as follows: 501-18. 505-21. Multiwire Branch Circuits. In a Class I, Division Zone 1 location, a multiwire branch circuit shall not be permitted. Exception: Where the disconnect device(s) for the circuit opens all ungrounded conductors of the multiwire circuit simultaneously. SUBSTANTIATION: This proposal is the work of a Task Group including Ed Briesch, Bill Lawrence, Dave Wechsler, Lon Ballard, Larry Fuhrman, and Will McBride. This Task Group was not balloted. The purpose of the proposal is to provide clear guidelines for wiring, sealing, and installation in Article 505, without having to refer to Article 501. PANEL ACTION: Accept in Principle. Add the proposed text to 505-22. PANEL STATEMENT: The Panel agrees with the text, but the correct location is 505-22. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #1541) 14- 199 - (501-18, Exception): Reject SUBMITTER: Thomas J. Conlan, Conlan's "The Electrician Inc." RECOMMENDATION: Revise to read as follows: 501-18. Multiwire Branch Circuits. In H11 location a multiwire branch circuit shall not be permitted. Exception: Where the disconnect device(s) for the circuit opens all ungrounded conductors of the multiwire circuit simultaneously. SUBSTANTIATION: Remove the exception. The disconnect does not address automatic or manual operation. Fusible disconnects can blow one fuse and not the other also a bad neutral can cause a higher voltage than 120 nominal on 120/240 volt multiwire branch circuit which can lead to a fire. PANEL ACTION: Reject. PANEL STATEMENT: The substantiation does not support the proposal. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________

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ARTICLE 502 -- CLASS II LOCATIONS

(Log #1260) 14- 200 - (502): Reject Note: It was the action of the Technical Correlating Committee that this Proposal be reconsidered by the Panel. The issues of raceway trade size, extracts, and use of soft versus hard metrication were all studied in detail and resolutions were communicated to the Panel prior to the Panel Meeting. It should be noted that all of the other Code-Making Panels accepted the metrication directive. This action will be considered by the Panel as a Public Comment. SUBMITTER: Technical Correlating Committee National Electrical Code RECOMMENDATION: In 502-2(b)(2)(c), change "6 in. (152 mm)" to "150 mm (6 in.)". In 502-5(2), change "10 ft (3.05 m)" to "3.0 m (10 ft)". In 502-5(3), change "5 ft (1.52 m)" to "1.5 m (5 ft)." In 502-11(a)(3), change "12 in. (305 mm) to "300 mm (12 in.)" in three places. In 502-11(b)(4), change "12 in. (305 mm)" to "300 mm (12 in.)" in three places. In 502-16(b), Exception (a), change "6 ft (1.83 m)" to "1.8 m (6 ft)." SUBSTANTIATION: The proposed revision complies with the NFPA 1M Manual of Style Section 4-1 with respect to the placement of units, i.e., to show the SI units as the preferred unit and the inch-pound units immediately following in parenthesis. PANEL ACTION: Reject. PANEL STATEMENT: Panel 14 believes the following issues need further evaluation before changes are made to the code: trade sizes of conduit; extract policies; consistency from article to article within the code. For example, trade size of conduit is not a true dimension and cannot be converted to a true metric number. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 9 NEGATIVE: 3 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: KUCZKA: See my Explanation of Negative Vote on Proposal 1410. OMEARA: This proposal should be accepted, to be in conformance with Chapter 4 of the NFPA MOS-1 Manual of Style. ZIPSE: See my Explanation of Negative Vote on Proposal 14-10.

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Dust-ignitionproof, as used in this article, shall mean enclosed in a manner that will exclude dusts and, where installed and protected in accordance with this Code, will not permit arcs, sparks, or heat otherwise generated or liberated inside of the enclosure to cause ignition of exterior accumulations or atmospheric suspensions of a specified dust on or in the vicinity of the enclosure. FPN: For further information on dust-ignitionproof enclosures, see Type 9 enclosure in Enclosures for Electrical Equipment, ANSI/NEMA 250-1991, and Explosionproof and Dust-Ignitionproof Electrical Equipment for Hazardous (Classified) Locations, ANSI/UL 1203-1994. Equipment installed in Class II locations shall be able to function at full rating without developing surface temperatures high enough to cause excessive dehydration or gradual carbonization of any organic dust deposits that may occur. FPN: Dust that is carbonized or excessively dry is highly susceptible to spontaneous ignition. Equipment and wiring of the type defined in Article 100 as explosionproof shall not be required and shall not be acceptable in Class II locations unless approved for such locations. Where Class II, Group E dusts are present in hazardous quantities, there are only Division 1 locations. 502-2. Transformers and Capacitors (a) Class II, Division 1. In Class II, Division 1 locations, transformers and capacitors shall comply with the following. (1) Containing Liquid that Will Burn. Transformers and capacitors containing a liquid that will burn shall be installed only in approved vaults complying with Sections 450-41 through 450-48, and, in addition, the following shall apply. a. Doors or other openings communicating with the Division 1 location shall have self-closing fire doors on both sides of the wall, and the doors shall be carefully fitted and provided with suitable seals (such as weather stripping) to minimize the entrance of dust into the vault. b. Vent openings and ducts shall communicate only with the outside air. c. Suitable pressure-relief openings communicating with the outside air shall be provided. (2) Not Containing Liquid that Will Burn. Transformers and capacitors that do not contain a liquid that will burn shall be installed in vaults complying with Sections 450-41 through 450-48 or be approved as a complete assembly, including terminal connections for Class II locations. (3) Metal Dusts. No transformer or capacitor shall be installed in a location where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present. (b) Class II, Division 2. In Class II, Division 2 locations, transformers and capacitors shall comply with the following. (1) Containing Liquid that Will Burn. Transformers and capacitors containing a liquid that will burn shall be installed in vaults that comply with Sections 450-41 through 450-48. (2) Containing Askarel. Transformers containing askarel and rated in excess of 25 kVA shall be as follows: a. Provided with pressure-relief vents b. Provided with a means for absorbing any gases generated by arcing inside the case, or the pressure-relief vents shall be connected to a chimney or flue that will carry such gases outside the building c. Have an airspace of not less than 6 in. (152 mm) between the transformer cases and any adjacent combustible material (3) Dry-Type Transformers. Dry-type transformers shall be installed in vaults or shall have their windings and terminal connections enclosed in tight metal housings without ventilating or other openings and shall operate at not over 600 volts, nominal. 502-4. Wiring Methods Wiring methods shall comply with (a) and (b). (a) Class II, Division 1 . In Class II, Division 1 locations, threaded rigid metal conduit, threaded steel intermediate metal conduit, or Type MI cable with termination fittings approved for the location shall be the wiring method employed. Type MI cable shall be installed and supported in a manner to avoid tensile stress at the termination fittings. Exception: In industrial establishments with limited public access, where the conditions of maintenance and supervision ensure that only qualified persons will service the installation, Type MC cable, listed for use in Class II, Division 1 locations, with a gas/vaportight

___________________ (Log #CP1412) 14- 200a - (502): Accept Note: The Technical Correlating Committee advises that Article Scope statements are the responsibility of the Technical Correlating Committee and the Technical Correlating Committee accepts the Panel Action. Further, it was the action of the Technical Correlating Committee that this Proposal be reconsidered by the Panel, with further consideration given to the comments expressed in the voting, specifically with respect to comments that the accepted Proposal does not accurately reflect what was agreed upon by the Panel. It is the understanding of the Technical Correlating Committee that this proposal is modified by Proposals 14-201, 14-202, 14-204, 14-205, 14-206, 14-207, 14-207a, 14208, 14-209, 14-210, 14-210a, 14-211, 14-212, 14-213, 14-216, 14-219, 14-223,14-224, 14-227, 14-228, 14-231, 14-232, 14-233, 14-234, 14-235, 14-236, 14-239, 14-240, 14-243, 14-244, 14-245, 14-246, 14-249, 14-250, 14-251, 14-252, 14-255, 14-256, 14-257, 14-258, 14-259, 14-262, 14-263, 14-264, 14-265, 14-266, 14-267, 14-268, 14-269, 14-270, and 14-271. This action will be considered by the Panel as a Public Comment. SUBMITTER: CMP 14 RECOMMENDATION: Revise Article 502 to read as follows: 502 ARTICLE 502 -- Class II Locations 502-1. General The general rules of this Code shall apply to the electric wiring and equipment in locations classified as Class II locations in Section 500-8. Exception: As modified by this article.

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continuous corrugated aluminum sheath, an overall jacket of suitable polymeric material, separate grounding conductors in accordance with Section 250-122, and provided with termination fittings listed for the application shall be permitted. (1) Fittings and Boxes. Fittings and boxes shall be provided with threaded bosses for connection to conduit or cable terminations, shall have close-fitting covers, and shall have no openings (such as holes for attachment screws) through which dust might enter or through which sparks or burning material might escape. Fittings and boxes in which taps, joints, or terminal connections are made, or that are used in locations where dusts are of a combustible, electrically conductive nature, shall be approved for Class II locations. (2) Flexible Connections. Where necessary to employ flexible connections, dusttight flexible connectors, liquidtight flexible metal conduit with approved fittings, liquidtight flexible nonmetallic conduit with approved fittings, or flexible cord approved for extra-hard usage and provided with bushed fittings shall be used. Where flexible cords are used, they shall comply with Section 502-12. Where flexible connections are subject to oil or other corrosive conditions, the insulation of the conductors shall be of a type approved for the condition or shall be protected by means of a suitable sheath. FPN: See Section 502-16(b) for grounding requirements where flexible conduit is used. (b) Class II, Division 2. In Class II, Division 2 locations, rigid metal conduit, intermediate metal conduit, electrical metallic tubing, dusttight wireways, Type MC or MI cable with approved termination fittings, Type PLTC in cable trays, Type ITC in cable trays, or Type MC, MI, or TC cable installed in ladder, ventilated trough, or ventilated channel cable trays in a single layer, with a space not less than the larger cable diameter between the two adjacent cables, shall be the wiring method employed. Exception No. 1: Nonincendive field wiring shall be permitted using any of the methods suitable for wiring in nonhazardous ordinary locations including Chapter 7 and 8 wiring methods.(14220) Exception No. 2: Type MC cable listed for use in Class II, Division 1 locations shall be permitted to be installed without the above required spacings. (1) Boxes and Fittings. All boxes and fittings shall be dusttight. (14-222) (1) Wireways, Fittings, and Boxes. Wireways, fittings, and boxes in which taps, joints, or terminal connections are made shall be designed to minimize the entrance of dust and (1) shall be provided with telescoping or close-fitting covers or other effective means to prevent the escape of sparks or burning material and (2) shall have no openings (such as holes for attachment screws) through which, after installation, sparks or burning material might escape or through which adjacent combustible material might be ignited. (2) Flexible Connections. Where flexible connections are necessary, (a)(2) shall apply. 502-5. Sealing, Class II, Divisions 1 and 2 Where a raceway provides communication between an enclosure that is required to be dust-ignitionproof and one that is not, suitable means shall be provided to prevent the entrance of dust into the dust-ignitionproof enclosure through the raceway. One of the following means shall be permitted: 1. A permanent and effective seal, 2. A horizontal raceway not less than 10 ft (3.05 m) long, or 3. A vertical raceway not less than 5 ft (1.52 m) long and extending downward from the dust-ignitionproof enclosure Where a raceway provides communication between an enclosure that is required to be dust-ignitionproof and an enclosure in an unclassified location, seals shall not be required. Sealing fittings shall be accessible. Seals shall not be required to be explosionproof. FPN: Electrical sealing putty is a method of sealing. 502-6. Switches, Circuit Breakers, Motor Controllers, and Fuses (a) Class II, Division 1. In Class II, Division 1 locations, switches, circuit breakers, motor controllers, and fuses shall comply with the following:

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(1) Type Required. Switches, circuit breakers, motor controllers, and fuses, including pushbuttons, relays, and similar devices that are intended to interrupt current during normal operation or that are installed where combustible dusts of an electrically conductive nature may be present, shall be provided with approved dustignitionproof enclosures. (2) Isolating Switches. Disconnecting and isolating switches containing no fuses and not intended to interrupt current and not installed where dusts may be of an electrically conductive nature shall be provided with tight metal enclosures that shall be designed to minimize the entrance of dust and that shall (1) be equipped with telescoping or close-fitting covers or with other effective means to prevent the escape of sparks or burning material and (2) have no openings (such as holes for attachment screws) through which, after installation, sparks or burning material might escape or through which exterior accumulations of dust or adjacent combustible material might be ignited. (3) Metal Dusts. In locations where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present, fuses, switches, motor controllers, and circuit breakers shall have enclosures identified specifically approved(14-225,226) for such locations. (b) Class II, Division 2 . In Class II, Division 2 locations, enclosures for fuses, switches, circuit breakers, and motor controllers, including pushbuttons, relays, and similar devices, shall be dusttight. 502-7. Control Transformers and Resistors (a) Class II, Division 1. In Class II, Division 1 locations, control transformers, solenoids, impedance coils, resistors, and any overcurrent devices or switching mechanisms associated with them shall have dust-ignitionproof enclosures approved for Class II locations. No control transformer, impedance coil, or resistor shall be installed in a location where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present unless provided with an enclosure approved for the specific location. (b) Class II, Division 2. In Class II, Division 2 locations, transformers and resistors shall comply with the following. (1) Switching Mechanisms. Switching mechanisms (including overcurrent devices) associated with control transformers, solenoids, impedance coils, and resistors shall be provided with dusttight enclosures. (2) Coils and Windings. Where not located in the same enclosure with switching mechanisms, control transformers, solenoids, and impedance coils shall be provided with tight metal housings without ventilating openings. (3) Resistors. Resistors and resistance devices shall have dustignitionproof enclosures identified approved for Class II locations.(14-229) Exception: Where the maximum normal operating temperature of the resistor will not exceed 120ºC (248ºF), nonadjustable resistors or resistors that are part of an automatically timed starting sequence shall be permitted to have enclosures complying with (b)(2). 502-8. Motors and Generators (a) Class II, Division 1. In Class II, Division 1 locations, motors, generators, and other rotating electrical machinery shall be 1. Approved for Class II, Division 1 locations, or 2. Totally enclosed pipe-ventilated, meeting temperature limitations in Section 502-1. (b) Class II, Division 2. In Class II, Division 2 locations, motors, generators, and other rotating electrical equipment shall be totally enclosed nonventilated, totally enclosed pipe-ventilated, totally enclosed water­air cooled, totally enclosed fan-cooled or dustignitionproof for which maximum full-load external temperature shall be in accordance with Section 500-5(f) for normal operation when operating in free air (not dust blanketed) and shall have no external openings. Exception: If the authority having jurisdiction believes accumulations of nonconductive, nonabrasive dust will be moderate and if machines can be easily reached for routine cleaning and maintenance, the following shall be permitted to be installed: a. Standard open-type machines without sliding contacts, centrifugal or other types of switching mechanism (including motor overcurrent, overloading, and overtemperature devices), or integral resistance devices

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b. Standard open-type machines with such contacts, switching mechanisms, or resistance devices enclosed within dusttight housings without ventilating or other openings c. Self-cleaning textile motors of the squirrel-cage type 502-9. Ventilating Piping Ventilating pipes for motors, generators, or other rotating electric machinery, or for enclosures for electric equipment, shall be of metal not less than 0.021 in. (533 µm) in thickness, or of equally substantial noncombustible material, and shall comply with the following: 1. Lead directly to a source of clean air outside of buildings, 2. Be screened at the outer ends to prevent the entrance of small animals or birds, and 3. Be protected against physical damage and against rusting or other corrosive influences Ventilating pipes shall also comply with (a) and (b). (a) Class II, Division 1. In Class II, Division 1 locations, ventilating pipes, including their connections to motors or to the dustignitionproof enclosures for other equipment, shall be dusttight throughout their length. For metal pipes, seams and joints shall comply with one of the following: 1. Be riveted and soldered, 2. Be bolted and soldered, 3. Be welded, or 4. Be rendered dusttight by some other equally effective means (b) Class II, Division 2. In Class II, Division 2 locations, ventilating pipes and their connections shall be sufficiently tight to prevent the entrance of appreciable quantities of dust into the ventilated equipment or enclosure and to prevent the escape of sparks, flame, or burning material that might ignite dust accumulations or combustible material in the vicinity. For metal pipes, lock seams and riveted or welded joints shall be permitted; and tight-fitting slip joints shall be permitted where some flexibility is necessary, as at connections to motors. 502-10. Utilization Equipment (a) Class II, Division 1. In Class II, Division 1 locations, all utilization equipment shall be approved for Class II locations. Where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present, such equipment shall be approved for the specific location. (b) Class II, Division 2. In Class II, Division 2 locations, all utilization equipment shall comply with the following. (1) Heaters. Electrically heated utilization equipment shall be approved for Class II locations. Exception: Metal-enclosed radiant heating panel equipment shall be dusttight and marked in accordance with Section 500-5(d). (2) Motors. Motors of motor-driven utilization equipment shall comply with Section 502-8(b). (3) Switches, Circuit Breakers, and Fuses. Enclosures for switches, circuit breakers, and fuses shall be dusttight. (4) Transformers, Solenoids, Impedance Coils, and Resistors. Transformers, solenoids, impedance coils, and resistors shall comply with Section 502-7(b). 502-11. Lighting Fixtures Lighting fixtures shall comply with (a) and (b). (a) Class II, Division 1. In Class II, Division 1 locations, lighting fixtures for fixed and portable lighting shall comply with the following. (1) Approved Fixtures. Each fixture shall be identified approved for Class II locations and shall be clearly marked to indicate the maximum wattage of the lamp for which it is designed approved . In locations where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present, fixtures for fixed or portable lighting and all auxiliary equipment shall be identified approved for the specific location. (14-237) (2) Physical Damage. Each fixture shall be protected against physical damage by a suitable guard or by location. (3) Pendant Fixtures. Pendant fixtures shall be suspended by threaded rigid metal conduit stems, threaded steel intermediate metal conduit stems, by chains with approved fittings, or by other approved means. For rigid stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of a fitting or a flexible connector approved for the location shall be provided not more than 12 in. (305 mm) from the point of attachment to the

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supporting box or fitting. Threaded joints shall be provided with set-screws or other effective means to prevent loosening. Where wiring between an outlet box or fitting and a pendant fixture is not enclosed in conduit, flexible cord approved for hard usage shall be used, and suitable seals shall be provided where the cord enters the fixture and the outlet box or fitting. Flexible cord shall not serve as the supporting means for a fixture. (4) Supports. Boxes, box assemblies, or fittings used for the support of lighting fixtures shall be approved for Class II locations. (b) Class II, Division 2. In Class II, Division 2 locations, lighting fixtures shall comply with the following. (1) Portable Lighting Equipment. Portable lighting equipment shall be identified approved for Class II locations. They shall be clearly marked to indicate the maximum wattage of lamps for which they are designed approved (14-247) . (2) Fixed Lighting. Lighting fixtures for fixed lighting, where not of a type approved for Class II locations, shall provide enclosures for lamps and lampholders that shall be designed to minimize the deposit of dust on lamps and to prevent the escape of sparks, burning material, or hot metal. Each fixture shall be clearly marked to indicate the maximum wattage of the lamp that shall be permitted without exceeding an exposed surface temperature in accordance with Section 500-5(f) under normal conditions of use. (3) Physical Damage. Lighting fixtures for fixed lighting shall be protected from physical damage by suitable guards or by location. (4) Pendant Fixtures. Pendant fixtures shall be suspended by threaded rigid metal conduit stems, threaded steel intermediate metal conduit stems, by chains with approved fittings, or by other approved means. For rigid stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of an approved fitting or a flexible connector shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting. Where wiring between an outlet box or fitting and a pendant fixture is not enclosed in conduit, flexible cord approved for hard usage shall be used. Flexible cord shall not serve as the supporting means for a fixture. (5) Electric-Discharge Lamps. Starting and control equipment for electric-discharge lamps shall comply with the requirements of Section 502-7(b). 502-12. Flexible Cords -- Class II, Divisions 1 and 2 Flexible cords used in Class II locations shall comply with the following: 1. Be of a type approved for extra-hard usage, FPN: Flexible cord listed for hard usage as permitted by Sections 502-11 (a) (3) and (b) (4). (14-257) 2. Contain, in addition to the conductors of the circuit, a grounding conductor complying with Section 400-23, 3. Be connected to terminals or to supply conductors in an approved manner, 4. Be supported by clamps or by other suitable means in such a manner that there will be no tension on the terminal connections, and 5. Be provided with suitable seals to prevent the entrance of dust where the flexible cord enters boxes or fittings that are required to be dust-ignitionproof 502-13. Receptacles and Attachment Plugs (a) Class II, Division 1. In Class II, Division 1 locations, receptacles and attachment plugs shall be of the type providing for connection to the grounding conductor of the flexible cord and shall be approved for Class II locations. (b) Class II, Division 2. In Class II, Division 2 locations, receptacles and attachment plugs shall be of the type that provide for connection to the grounding conductor of the flexible cord and shall be designed so that connection to the supply circuit cannot be made or broken while live parts are exposed. 502-14. Signaling, Alarm, Remote-Control, and Communications Systems; and Meters, Instruments, and Relays FPN: See Article 800 for rules governing the installation of communications circuits. (a) Class II, Division 1. In Class II, Division 1 locations, signaling, alarm, remote-control, and communications systems; and meters, instruments, and relays shall comply with the following: (1) Wiring Methods. The wiring method shall comply with Section 502-4(a).

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(2) Contacts. Switches, circuit breakers, relays, contactors, fuses and current-breaking contacts for bells, horns, howlers, sirens, and other devices in which sparks or arcs may be produced shall be provided with enclosures approved for a Class II location. Exception: Where current-breaking contacts are immersed in oil or where the interruption of current occurs within a chamber sealed against the entrance of dust, enclosures shall be permitted to be of the general-purpose type. (3) Resistors and Similar Equipment. Resistors, transformers, choke coils, rectifiers, thermionic tubes, and other heat-generating equipment shall be provided with enclosures approved for Class II locations. Exception: Where resistors or similar equipment are immersed in oil or enclosed in a chamber sealed against the entrance of dust, enclosures shall be permitted to be of the general-purpose type. (4) Rotating Machinery. Motors, generators, and other rotating electric machinery shall comply with Section 502-8(a). (5) Combustible, Electrically Conductive Dusts. Where dusts are of a combustible, electrically conductive nature, all wiring and equipment shall be approved for Class II locations. (6) Metal Dusts. Where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present, all apparatus and equipment shall be approved for the specific conditions. (b) Class II, Division 2. In Class II, Division 2 locations, signaling, alarm, remote-control, and communications systems; and meters, instruments, and relays shall comply with the following. (1) Contacts. Enclosures shall comply with (a)(2), or contacts shall have tight metal enclosures designed to minimize the entrance of dust and shall have telescoping or tight-fitting covers and no openings through which, after installation, sparks or burning material might escape. Exception: In nonincendive circuits, enclosures shall be permitted to be of the general-purpose type. (2) Transformers and Similar Equipment. The windings and terminal connections of transformers, choke coils, and similar equipment shall be provided with tight metal enclosures without ventilating openings. (3) Resistors and Similar Equipment. Resistors, resistance devices, thermionic tubes, rectifiers, and similar equipment shall comply with (a)(3). Exception: Enclosures for thermionic tubes, nonadjustable resistors, or rectifiers for which maximum operating temperature will not exceed 120ºC (248ºF) shall be permitted to be of the general-purpose type. (4) Rotating Machinery. Motors, generators, and other rotating electric machinery shall comply with Section 502-8(b). (5) Wiring Methods. The wiring method shall comply with Section 502-4(b). 502-15. Live Parts, Class II, Divisions 1 and 2 Live parts shall not be exposed. 502-16. Grounding, Class II, Divisions 1 and 2 Wiring and equipment in Class II, Divisions 1 and 2 locations shall be grounded as specified in Article 250 and with the following additional requirements. (a) Bonding. The locknut-bushing and double-locknut types of contact shall not be depended on for bonding purposes, but bonding jumpers with proper fittings or other approved means of bonding shall be used. Such means of bonding shall apply to all intervening raceways, fittings, boxes, enclosures, etc., between Class II locations and the point of grounding for service equipment or point of grounding of a separately derived system. Exception: The specific bonding means shall only be required to the nearest point where the grounded circuit conductor and the grounding electrode conductor are connected together on the line side of the building or structure disconnecting means as specified in Sections 250-32(a), (b), and (c), if the branch-circuit overcurrent protection is located on the load side of the disconnecting means. FPN: See Section 250-100 for additional bonding requirements in hazardous (classified) locations. (b) Types of Equipment Grounding Conductors. Where flexible conduit is used as permitted in Section 502-4, it shall be installed with internal or external bonding jumpers in parallel with each conduit and complying with Section 250-102. Exception: In Class II, Division 2 locations, the bonding jumper shall be permitted to be deleted where all the following conditions are met. a. Listed liquidtight flexible metal conduit 6 ft (1.83 m) or less in length, with fittings listed for grounding, is used.

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b. Overcurrent protection in the circuit is limited to 10 amperes or less. c. The load is not a power utilization load. 502-17. Surge Protection -- Class II, Divisions 1 and 2 Surge arresters, including their installation and connection, shall comply with Article 280. In addition, surge arresters, if installed in a Class II, Division 1 location, shall be in suitable enclosures. Surge-protective capacitors shall be of a type designed for specific duty. 502-18. Multiwire Branch Circuits In a Class II, Division 1 location, a multiwire branch circuit shall not be permitted. Exception: Where the disconnect device(s) for the circuit opens all ungrounded conductors of the multiwire circuit simultaneously. SUBSTANTIATION: This complete revision of Article 502 editorially revises the text to make it more easily understood and also incorporates numerous technical and editorial improvements made via other proposals. PANEL ACTION: Accept. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban COMMENT ON AFFIRMATIVE: BRIESCH: While the Panel Action to accept the rewrite of Article 502 is supported, the NFPA-circulated Panel Proposal does not include all of the changes agreed to at the meeting. The e-mail sent by Dave Wechsler subsequent to the meeting is more complete in reflecting the Panel Actions from the meeting. COOK: I agree with Proposal 14-200a and the substantiation, however, it does not incorporate all of the changes made via other proposals. An updated version that was emailed from Dave Wechsler on 1-26-2000 seems to be more complete with respect to including Panel Actions from the meeting in Hilton Head. ENGLER: Not all of the changes made it into the draft circulated with this ballot, vote is to affirm the text with all of the necessary changes made to it. JAGUNICH: The panel proposal sent with the ballot material does not appear to be consistent with CMP14's intent, as expressed during the panel meeting. This rewrite should reexamined and modified as necessary. LAWRENCE: Due to the large number of public proposals received and acted upon and also due to time constraints, the panel was not able to compile and correlate all aspects of the rewrites of the affected article. Please see David Wechsler's ballot. OMEARA: Please see the comments on the ballot for David Wechsler. WECHSLER: While attempts were made to provide NFPA Staff with corrected revisions of this text before the end of the CMP 14 panel meeting, a detailed review of this balloted draft version has indicated that this does not reflect the accurate committee actions and is not correct. We attribute the problems with this draft to the following: a) the use of several earlier drafts that were consistently being revised to keep pace with changes made due to committee actions on public proposals, b) the limited time available to proof and develop this work, c) the extremely large number of public proposals, d) the complex nature of the interaction of affected texts within Articles 500, 501, 502 and 505, and the desire of the committee to maintain consistency, and e) human errors in transcribing this information. The following text provides a correct revision of this complete work effort for Article 502. This text should be the panel document of record and not that provided with the panel ballot. ARTICLE 502 -- Class II Locations 502-1. General The general rules of this Code shall apply to the electric wiring and equipment in locations classified as Class II locations in Section 500-5(c)500-8. Exception: As modified by this article. Dust-ignitionproof, as used in this article, shall mean enclosed in a manner that will exclude dusts and, where installed and protected in accordance with this Code, will not permit arcs, sparks, or heat otherwise generated or liberated inside of the enclosure to cause ignition of exterior accumulations or atmospheric suspensions of a specified dust on or in the vicinity of the enclosure.

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FPN: For further information on dust-ignitionproof enclosures, see Type 9 enclosure in Enclosures for Electrical Equipment, ANSI/NEMA 250-1991, and Explosionproof and Dust-Ignitionproof Electrical Equipment for Hazardous (Classified) Locations, ANSI/UL 1203-1994. Equipment installed in Class II locations shall be able to function at full rating without developing surface temperatures high enough to cause excessive dehydration or gradual carbonization of any organic dust deposits that may occur. FPN: Dust that is carbonized or excessively dry is highly susceptible to spontaneous ignition. Equipment and wiring of the type defined in Article 100 as explosionproof shall not be required and shall not be acceptable in Class II locations unless identified approved [14-201, 14-202] for such locations. Where Class II, Group E dusts are present in hazardous quantities, there are only Division 1 locations. 502-2. Transformers and Capacitors (a) Class II, Division 1. In Class II, Division 1 locations, transformers and capacitors shall comply with the following. (1) Containing Liquid that Will Burn. Transformers and capacitors containing a liquid that will burn shall be installed only in approved [14-204,14-205] vaults complying with Sections 450-41 through 450-48, and, in addition, the following shall apply. a. Doors or other openings communicating with the Division 1 location shall have self-closing fire doors on both sides of the wall, and the doors shall be carefully fitted and provided with suitable seals (such as weather stripping) to minimize the entrance of dust into the vault. b. Vent openings and ducts shall communicate only with the outside air. c. Suitable pressure-relief openings communicating with the outside air shall be provided. (2) Not Containing Liquid that Will Burn. Transformers and capacitors that do not contain a liquid that will burn shall be installed in vaults complying with Sections 450-41 through 450-48 or be identified approved [14-206,14-207] as a complete assembly, including terminal connections for Class II locations. (3) Metal Dusts. No transformer or capacitor shall be installed in a location where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present. (b) Class II, Division 2. In Class II, Division 2 locations, transformers and capacitors shall comply with the following. (1) Containing Liquid that Will Burn. Transformers and capacitors containing a liquid that will burn shall be installed in vaults that comply with Sections 450-41 through 450-48. (2) Containing Askarel. Transformers containing askarel and rated in excess of 25 kVA shall be as follows: a. Provided with pressure-relief vents b. Provided with a means for absorbing any gases generated by arcing inside the case, or the pressure-relief vents shall be connected to a chimney or flue that will carry such gases outside the building c. Have an airspace of not less than 6 in. (152 mm) between the transformer cases and any adjacent combustible material (3) Dry-Type Transformers. Dry-type transformers shall be installed in vaults or shall have their windings and terminal connections enclosed in tight metal housings without ventilating or other openings and shall operate at not over 600 volts, nominal. 502-4. Wiring Methods Wiring methods shall comply with (a) or and (b). (CP-1409 to correlate with 501-4) (a) Class II, Division 1 . In Class II, Division 1 locations, threaded rigid metal conduit, threaded steel intermediate metal conduit, or Type MI cable with termination fittings listed approved [14-208,14209] for the location shall be the wiring method employed. Type MI cable shall be installed and supported in a manner to avoid tensile stress at the termination fittings. Exception: In industrial establishments with limited public access, where the conditions of maintenance and supervision ensure that only qualified persons will service the installation, Type MC cable, listed for use in Class II, Division 1 locations, with a gas/vaportight continuous corrugated metallic aluminum [14-210] sheath, an overall jacket of suitable polymeric material, separate grounding

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conductors in accordance with Section 250-122, and provided with termination fittings listed for the application shall be permitted. (1) Fittings and Boxes. Fittings and boxes shall be provided with threaded bosses for connection to conduit or cable terminations and shall be dust-tight. Fittings and boxes in which taps, joints, or terminal connections are made, or that are used in Group E, shall be identified for Class II locations. , shall have close-fitting covers, and shall have no openings (such as holes for attachment screws) through which dust might enter or through which sparks or burning material might escape. Fittings and boxes in which taps, joints, or terminal connections are made, or that are used in locations where dusts are of a combustible, electrically conductive nature, shall be approved for Class II locations. ( 14-211,14-212, CP1408) (2) Flexible Connections. Where necessary to employ flexible connections, dusttight flexible connectors, liquidtight flexible metal conduit with approved fittings, liquidtight flexible nonmetallic conduit with listed approved fittings, or flexible cord listed approved for extra-hard usage and provided with bushed fittings shall be used. Where flexible cords are used, they shall comply with Section 502-12. Where flexible connections are subject to oil or other corrosive conditions, the insulation of the conductors shall be of a type listed approved for the condition or shall be protected by means of a suitable sheath. [14-213] FPN: See Section 502-16(b) for grounding requirements where flexible conduit is used. (b) Class II, Division 2. In Class II, Division 2 locations, rigid metal conduit, intermediate metal conduit, electrical metallic tubing, dusttight wireways, Type MC or MI cable with listed approved [14-216 ,14-219] termination fittings, Type PLTC in cable trays, Type ITC in cable trays, or Type MC, MI, or TC cable installed in ladder, ventilated trough, or ventilated channel cable trays in a single layer, with a space not less than the larger cable diameter between the two adjacent cables, shall be the wiring method employed. Exception No. 1: Nonincendive field wiring shall be permitted using any of the methods suitable for wiring in nonhazardous ordinary locations including Chapter 7 and 8 wiring methods.(14220) Exception No. 2: Type MC cable listed for use in Class II, Division 1 locations shall be permitted to be installed without the above required spacings. (1) Boxes and Fittings. All boxes and fittings shall be dusttight. ( 14-221,14-222) (1) Wireways, Fittings, and Boxes. Wireways, fittings, and boxes in which taps, joints, or terminal connections are made shall be designed to minimize the entrance of dust and (1) shall be provided with telescoping or close-fitting covers or other effective means to prevent the escape of sparks or burning material and (2) shall have no openings (such as holes for attachment screws) through which, after installation, sparks or burning material might escape or through which adjacent combustible material might be ignited. (2) Flexible Connections. Where flexible connections are necessary, (a)(2) shall apply. Rewrite of above section 502-4 to correlate with 501-4 and as modified by Proposals 502-4. Wiring Methods Wiring methods shall comply with (a) or (b). (CP-1409 to correlate with 501-4) (a) Class II, Division 1 . (1) In Class II, Division 1 locations, the following wiring methods shall be permitted: (a) Threaded rigid metal conduit, or threaded steel intermediate metal conduit may be used. (b) Type MI cable with termination fittings listed [14-208,14-209] for the location. Type MI cable shall be installed and supported in a manner to avoid tensile stress at the termination fittings.

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(c) In industrial establishments with limit ed public access, where the conditions of maintenance and supervision ensure that only qualified persons will service the installation, Type MC cable, listed for use in Class II, Division 1 locations, with a gas/vaportight continuous corrugated metallic [14-210] sheath, an overall jacket of suitable polymeric material, separate grounding conductors in accordance with Section 250-122, and provided with termination fittings listed for the application shall be permitted. (d) Fittings and boxes shall be prov ided with threaded bosses for connection to conduit or cable terminations and shall be dust-tight. Fittings and boxes in which taps, joints, or terminal connections are made, or that are used in Group E, shall be identified for Class II locations. (14-211,14-212,CP-1408) (e) Where necessary to employ flexible connections, dusttight flexible connectors, liquidtight flexible metal conduit with listed fittings, liquidtight flexible nonmetallic conduit with listed fittings, or flexible cord listed for extra- hard usage and provided with bushed fittings shall be used. Where flexible cords are used, they shall comply with Section 502-12. Where flexible connections are subject to oil or other corrosive conditions, the insulation of the conductors shall be of a type listed for the condition or shall be protected by means of a suitable sheath. [14-213] FPN: See Section 502-16(b) for grounding requirements where flexible conduit is used. (b) Class II, Division 2. (1) In Class II, Division 2 locations, the following wiring methods shall be permitted: a. Rigid metal conduit, intermediate metal conduit, electrical metallic tubing, b. Dusttight wireways, c. Type MC or MI cable with listed [14-216,14219]termination fittings, d. Type PLTC in cable trays, e. Type ITC in cable trays, f. Type M C, MI, or TC cable installed in ladder, ventilated trough, or ventilated channel cable trays in a single layer, with a space not less than the larger cable diameter between the two adjacent cables, shall be the wiring method employed. Exception: Type MC ble listed for use in Class II, Division 1 ca locations shall be permitted to be installed without the above required spacings. (2) Where provision must be made for flexibility apply 502-4 (a)(1) (e.) (3) Nonincendive field wiring shall be permitted using any of the wiring methods permitted for nonhazardous [14-81,14-88,1401, 14220] locations, including Chapter 7 and 8 wiring methods. Nonincendive field wiring systems shall be installed in accordance with the control drawing(s). (14-83) (4) All boxes and fittings shall be dusttight. (14-221,14-222) 502-5. Sealing, Class II, Divisions 1 and 2 Where a raceway provides communication between an enclosure that is required to be dust-ignitionproof and one that is not, suitable means shall be provided to prevent the entrance of dust into the dust-ignitionproof enclosure through the raceway. One of the following means shall be permitted: 1. A permanent and effective seal, 2. A horizontal raceway not less than 10 ft (3.05 m) long, or

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3. A vertical raceway not less than 5 ft (1.52 m) long and extending downward from the dust-ignitionproof enclosure Where a raceway provides communication between an enclosure that is required to be dust-ignitionproof and an enclosure in an unclassified location, seals shall not be required. Sealing fittings shall be accessible. Seals shall not be required to be explosionproof. FPN: Electrical sealing putty is a method of sealing. 502-6. Switches, Circuit Breakers, Motor Controllers, and Fuses (a) Class II, Division 1. In Class II, Division 1 locations, switches, circuit breakers, motor controllers, and fuses shall comply with the following: (1) Type Required. Switches, circuit breakers, motor controllers, and fuses, including pushbuttons, relays, and similar devices that are intended to interrupt current during normal operation or that are installed where combustible dusts of an electrically conductive nature may be present, shall be provided with identified approved [14-223,14-224] dust-ignitionproof enclosures. (2) Isolating Switches. Disconnecting and isolating switches containing no fuses and not intended to interrupt current and not installed where dusts may be of an electrically conductive nature shall be provided with tight metal enclosures that shall be designed to minimize the entrance of dust and that shall (1) be equipped with telescoping or close-fitting covers or with other effective means to prevent the escape of sparks or burning material and (2) have no openings (such as holes for attachment screws) through which, after installation, sparks or burning material might escape or through which exterior accumulations of dust or adjacent combustible material might be ignited. (3) Metal Dusts. In locations where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present, fuses, switches, motor controllers, and circuit breakers shall have enclosures identified specifically approved(14-225, 14-226) for such locations. (b) Class II, Division 2 . In Class II, Division 2 locations, enclosures for fuses, switches, circuit breakers, and motor controllers, including pushbuttons, relays, and similar devices, shall be dusttight. 502-7. Control Transformers and Resistors (a) Class II, Division 1. In Class II, Division 1 locations, control transformers, solenoids, impedance coils, resistors, and any overcurrent devices or switching mechanisms associated with them shall have dust-ignitionproof enclosures approved for Class II locations. No control transformer, impedance coil, or resistor shall be installed in a location where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present unless provided with an enclosure identified approved [14-227, 14-228] for the specific location. (b) Class II, Division 2. In Class II, Division 2 locations, transformers and resistors shall comply with the following. (1) Switching Mechanisms. Switching mechanisms (including overcurrent devices) associated with control transformers, solenoids, impedance coils, and resistors shall be provided with dusttight enclosures. (2) Coils and Windings. Where not located in the same enclosure with switching mechanisms, control transformers, solenoids, and impedance coils shall be provided with tight metal housings without ventilating openings. (3) Resistors. Resistors and resistance devices shall have dustignitionproof enclosures identified approved for Class II locations.(14-229,14-230) Exception: Where the maximum normal operating temperature of the resistor will not exceed 120ºC (248ºF), nonadjustable resistors or resistors that are part of an automatically timed starting sequence shall be permitted to have enclosures complying with (b)(2). 502-8. Motors and Generators (a) Class II, Division 1. In Class II, Division 1 locations, motors, generators, and other rotating electrical machinery shall be 1. Identified Approved [14-231, 14-232] for Class II, Division 1 locations, or 2. Totally enclosed pipe-ventilated, meeting temperature limitations in Section 502-1. (b) Class II, Division 2. In Class II, Division 2 locations, motors, generators, and other rotating electrical equipment shall be totally

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enclosed nonventilated, totally enclosed pipe-ventilated, totally enclosed water­air cooled, totally enclosed fan-cooled or dustignitionproof for which maximum full-load external temperature shall be in accordance with Section 500-8(c)(2) 500-5(f) for normal operation when operating in free air (not dust blanketed) and shall have no external openings. Exception: If the authority having jurisdiction believes accumulations of nonconductive, nonabrasive dust will be moderate and if machines can be easily reached for routine cleaning and maintenance, the following shall be permitted to be installed: a. Standard open-type machines without sliding contacts, centrifugal or other types of switching mechanism (including motor overcurrent, overloading, and overtemperature devices), or integral resistance devices b. Standard open-type machines with such contacts, switching mechanisms, or resistance devices enclosed within dusttight housings without ventilating or other openings c. Self-cleaning textile motors of the squirrel-cage type 502-9. Ventilating Piping Ventilating pipes for motors, generators, or other rotating electric machinery, or for enclosures for electric equipment, shall be of metal not less than 0.021 in. (533 µm) in thickness, or of equally substantial noncombustible material, and shall comply with the following: 1. Lead directly to a source of clean air outside of buildings, 2. Be screened at the outer ends to prevent the entrance of small animals or birds, and 3. Be protected against physical damage and against rusting or other corrosive influences Ventilating pipes shall also comply with (a) and (b). (a) Class II, Division 1. In Class II, Division 1 locations, ventilating pipes, including their connections to motors or to the dustignitionproof enclosures for other equipment, shall be dusttight throughout their length. For metal pipes, seams and joints shall comply with one of the following: 1. Be riveted and soldered, 2. Be bolted and soldered, 3. Be welded, or 4. Be rendered dusttight by some other equally effective means (b) Class II, Division 2. In Class II, Division 2 locations, ventilating pipes and their connections shall be sufficiently tight to prevent the entrance of appreciable quantities of dust into the ventilated equipment or enclosure and to prevent the escape of sparks, flame, or burning material that might ignite dust accumulations or combustible material in the vicinity. For metal pipes, lock seams and riveted or welded joints shall be permitted; and tight-fitting slip joints shall be permitted where some flexibility is necessary, as at connections to motors. 502-10. Utilization Equipment (a) Class II, Division 1. In Class II, Division 1 locations, all utilization equipment shall be identified approved [14-233,14-234] for Class II locations. Where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present, such equipment shall be approved for the specific location. (b) Class II, Division 2. In Class II, Division 2 locations, all utilization equipment shall comply with the following. (1) Heaters. Electrically heated utilization equipment shall be identified approved [14-235,14-236] for Class II locations. Exception: Metal-enclosed radiant heating panel equipment shall be dusttight and marked in accordance with Section 500-8 (b) 5005(d) . (2) Motors. Motors of motor-driven utilization equipment shall comply with Section 502-8(b). (3) Switches, Circuit Breakers, and Fuses. Enclosures for switches, circuit breakers, and fuses shall be dusttight. (4) Transformers, Solenoids, Impedance Coils, and Resistors. Transformers, solenoids, impedance coils, and resistors shall comply with Section 502-7(b). 502-11. Lighting Fixtures Lighting fixtures shall comply with (a) and (b). (a) Class II, Division 1. In Class II, Division 1 locations, lighting fixtures for fixed and portable lighting shall comply with the following. (1) Approved Fixtures. Each fixture shall be identified approved for Class II locations and shall be clearly marked to indicate the

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maximum wattage of the lamp for which it is designed approved . In locations where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present, fixtures for fixed or portable lighting and all auxiliary equipment shall be identified approved for the specific location. (14-237 ,14-238) (2) Physical Damage. Each fixture shall be protected against physical damage by a suitable guard or by location. (3) Pendant Fixtures. Pendant fixtures shall be suspended by threaded rigid metal conduit stems, threaded steel intermediate metal conduit stems, by chains with approved fittings, or by other approved means. For rigid stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of a fitting or a flexible connector listed approved [14-240,14-243] for the location shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting. Threaded joints shall be provided with set-screws or other effective means to prevent loosening. Where wiring between an outlet box or fitting and a pendant fixture is not enclosed in conduit, flexible cord listed approved [14-239 ,14-244] for hard usage shall be used, and suitable seals shall be provided where the cord enters the fixture and the outlet box or fitting. Flexible cord shall not serve as the supporting means for a fixture. (4) Supports. Boxes, box assemblies, or fittings used for the support of lighting fixtures shall be identified approved [14-245,14246] for Class II locations. (b) Class II, Division 2. In Class II, Division 2 locations, lighting fixtures shall comply with the following. (1) Portable Lighting Equipment. Portable lighting equipment shall be identified approved for Class II locations. They shall be clearly marked to indicate the maximum wattage of lamps for which they are designed approved [14-247 ,14-248] . (2) Fixed Lighting. Lighting fixtures for fixed lighting, where not of a type identified approved [14-249,14-250] for Class II locations, shall provide enclosures for lamps and lampholders that shall be designed to minimize the deposit of dust on lamps and to prevent the escape of sparks, burning material, or hot metal. Each fixture shall be clearly marked to indicate the maximum wattage of the lamp that shall be permitted without exceeding an exposed surface temperature in accordance with Section 500-8 (c)(2) 500-5(f) under normal conditions of use. (3) Physical Damage. Lighting fixtures for fixed lighting shall be protected from physical damage by suitable guards or by location. (4) Pendant Fixtures. Pendant fixtures shall be suspended by threaded rigid metal conduit stems, threaded steel intermediate metal conduit stems, by chains with approved fittings, or by other approved means. For rigid stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of an approved fitting or a flexible connector shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting. Where wiring between an outlet box or fitting and a pendant fixture is not enclosed in conduit, flexible cord listed approved [14-251,14-256] for hard usage shall be used. Flexible cord shall not serve as the supporting means for a fixture. (5) Electric-Discharge Lamps. Starting and control equipment for electric-discharge lamps shall comply with the requirements of Section 502-7(b). 502-12. Flexible Cords -- Class II, Divisions 1 and 2 Flexible cords used in Class II locations shall comply with the following: 1. Be of a type listed approved [14-258,14-259] for extra-hard usage, FPN: Flexible cord listed for hard usage as permitted by Sections 502-11 (a) (3) and (b) (4). (14-257) 2. Contain, in addition to the conductors of the circuit, a grounding conductor complying with Section 400-23, 3. Be connected to terminals or to supply conductors in an approved manner, 4. Be supported by clamps or by other suitable means in such a manner that there will be no tension on the terminal connections, and 5. Be provided with suitable seals to prevent the entrance of dust where the flexible cord enters boxes or fittings that are required to be dust-ignitionproof

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502-13. Receptacles and Attachment Plugs (a) Class II, Division 1. In Class II, Division 1 locations, receptacles and attachment plugs shall be of the type providing for connection to the grounding conductor of the flexible cord and shall be identified approved [14-262,14-263] for Class II locations. (b) Class II, Division 2. In Class II, Division 2 locations, receptacles and attachment plugs shall be of the type that provide for connection to the grounding conductor of the flexible cord and shall be designed so that connection to the supply circuit cannot be made or broken while live parts are exposed. 502-14. Signaling, Alarm, Remote-Control, and Communications Systems; and Meters, Instruments, and Relays FPN: See Article 800 for rules governing the installation of communications circuits. (a) Class II, Division 1. In Class II, Division 1 locations, signaling, alarm, remote-control, and communications systems; and meters, instruments, and relays shall comply with the following: (1) Wiring Methods. The wiring method shall comply with Section 502-4(a). (2) Contacts. Switches, circuit breakers, relays, contactors, fuses and current-breaking contacts for bells, horns, howlers, sirens, and other devices in which sparks or arcs may be produced shall be provided with enclosures identified approved [14-264,14-265] for a Class II location. Exception: Where current-breaking contacts are immersed in oil or where the interruption of current occurs within a chamber sealed against the entrance of dust, enclosures shall be permitted to be of the general-purpose type. (3) Resistors and Similar Equipment. Resistors, transformers, choke coils, rectifiers, thermionic tubes, and other heat-generating equipment shall be provided with enclosures identified approved [14-266,14-267] for Class II locations. Exception: Where resistors or similar equipment are immersed in oil or enclosed in a chamber sealed against the entrance of dust, enclosures shall be permitted to be of the general-purpose type. (4) Rotating Machinery. Motors, generators, and other rotating electric machinery shall comply with Section 502-8(a). (5) Combustible, Electrically Conductive Dusts. Where dusts are of a combustible, electrically conductive nature, all wiring and equipment shall be identified approved [14-268,14-269] for Class II locations. (6) Metal Dusts. Where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present, all apparatus and equipment shall be identified approved [14-270,14-271] for the specific conditions. (b) Class II, Division 2. In Class II, Division 2 locations, signaling, alarm, remote-control, and communications systems; and meters, instruments, and relays shall comply with the following. (1) Contacts. Enclosures shall comply with (a)(2), or contacts shall have tight metal enclosures designed to minimize the entrance of dust and shall have telescoping or tight-fitting covers and no openings through which, after installation, sparks or burning material might escape. Exception: In nonincendive circuits, enclosures shall be permitted to be of the general-purpose type. (2) Transformers and Similar Equipment. The windings and terminal connections of transformers, choke coils, and similar equipment shall be provided with tight metal enclosures without ventilating openings. (3) Resistors and Similar Equipment. Resistors, resistance devices, thermionic tubes, rectifiers, and similar equipment shall comply with (a)(3). Exception: Enclosures for thermionic tubes, nonadjustable resistors, or rectifiers for which maximum operating temperature will not exceed 120ºC (248ºF) shall be permitted to be of the general-purpose type. (4) Rotating Machinery. Motors, generators, and other rotating electric machinery shall comply with Section 502-8(b). (5) Wiring Methods. The wiring method shall comply with Section 502-4(b). 502-15. Live Parts, Class II, Divisions 1 and 2 Live parts shall not be exposed. 502-16. Grounding, Class II, Divisions 1 and 2 Wiring and equipment in Class II, Divisions 1 and 2 locations shall be grounded as specified in Article 250 and with the following additional requirements.

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(a) Bonding. The locknut-bushing and double-locknut types of contact shall not be depended on for bonding purposes, but bonding jumpers with proper fittings or other approved means of bonding shall be used. Such means of bonding shall apply to all intervening raceways, fittings, boxes, enclosures, etc., between Class II locations and the point of grounding for service equipment or point of grounding of a separately derived system. Exception: The specific bonding means shall only be required to the nearest point where the grounded circuit conductor and the grounding electrode conductor are connected together on the line side of the building or structure disconnecting means as specified in Sections 250-32(a), (b), and (c), if the branch-circuit overcurrent protection is located on the load side of the disconnecting means. FPN: See Section 250-100 for additional bonding requirements in hazardous (classified) locations. (b) Types of Equipment Grounding Conductors. Where flexible conduit is used as permitted in Section 502-4, it shall be installed with internal or external bonding jumpers in parallel with each conduit and complying with Section 250-102. Exception: In Class II, Division 2 locations, the bonding jumper shall be permitted to be deleted where all the following conditions are met. a. Listed liquidtight flexible metal conduit 6 ft (1.83 m) or less in length, with fittings listed for grounding, is used. b. Overcurrent protection in the circuit is limited to 10 amperes or less. c. The load is not a power utilization load. 502-17. Surge Protection -- Class II, Divisions 1 and 2 Surge arresters, including their installation and connection, shall comply with Article 280. In addition, surge arresters, if installed in a Class II, Division 1 location, shall be in suitable enclosures. Surge-protective capacitors shall be of a type designed for specific duty. 502-18. Multiwire Branch Circuits In a Class II, Division 1 location, a multiwire branch circuit shall not be permitted. Exception: Where the disconnect device(s) for the circuit opens all ungrounded conductors of the multiwire circuit simultaneously. ___________________ (Log #1960) 14- 201 - (502-1): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise the fourth paragraph to read as follows: Equipment and wiring of the type defined in Article 100 as explosionproof shall not be required and shall not be acceptable in Class II locations unless approved (identified) for such locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________

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(Log #3522) 14- 202 - (502-1): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the fourth paragraph to read as follows: "Equipment and wiring of the type defined in Article 100 as explosionproof shall not be required and shall not be acceptable in Class II locations unless approved (identified) for such locations." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1793) 14- 203 - (502-1-Dust-ignitionproof): Accept in Principle Note: The Technical Correlating Committee directs that the Panel clarify the Panel Action and Statement on this Proposal. Companion Proposal 1-127 was rejected by Code-Making Panel 1. Code-Making Panel 14 has included a definition for Dustignitionproof in both Articles 500 (Proposal 14-2a) and 502 (Proposal 14-200a) and has not deleted the text as recommended by the submitter. This action will be considered by the Panel as a Public Comment. SUBMITTER: Noel Williams, Noel Williams Consulting RECOMMENDATION: Relocate the definition of Dustignitionproof and the related FPN to Article 100, and delete the text that applies the definition only to Article 502. SUBSTANTIATION: The term "Dust-ignitionproof" is used in both Articles 500 and 502. For the purposes of Article 500 the term is undefined because the definition in Article 502 applies only to Article 502. In addition, according to Section 500-4(b) FPN, "Dust-ignitionproof equipment is defined in Article 100." A similar proposal was made for the 1999 NEC and it was rejected by Panel 14. It is difficult to understand why the panel insisted on allowing and the TC allowed this plain error to continue. As presently located this definition contradicts the scope statement of Article 100, violates the manual of style, allows an undefined terms to be used in Article 500, and makes the statement of the fine print note in Section 500-4(b) false and misleading. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-2a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1793a) 1- 313 - (502-1-Dust-ignitionproof): Reject SUBMITTER: Noel Williams, Noel Williams Consulting RECOMMENDATION: Relocate the definition of Dustignitionproof and the related FPN to Article 100, and delete the text that applies the definition only to Article 502. SUBSTANTIATION: The term "Dust-ignitionproof" is used in both Articles 500 and 502. For the purposes of Article 500 the term is undefined because the definition in Article 502 applies only to Article 502. In addition, according to Section 500-4(b) FPN, "Dust-ignitionproof equipment is defined in Article 100." A similar proposal was made for the 1999 NEC and it was rejected by Panel 14. It is difficult to understand why the panel insisted on allowing and the TC allowed this plain error to continue. As presently located this definition contradicts the scope statement of Article 100, violates the manual of style, allows an undefined terms to be used in Article 500, and makes the statement of the fine print

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note in Section 500-4(b) false and misleading. PANEL ACTION: Reject. PANEL STATEMENT: The panel believes the definition is more appropriate in Article 502. Refer to CMP-14 for comment. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 13 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 1 Macias ___________________ (Log #2652) 14- 204 - (502-2(a)(1)): Accept in Part SUBMITTER: Donald R. Cook, Southern Section, IAEI RECOMMENDATION: Revise text to read as follows: (1) Containing Liquid that Will Burn. Transformers and capacitors containing liquid that will burn shall be installed only in approved (identified) vaults that comply with Sections 450-41 through 450-48, and, in addition, the following shall apply. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. Delete the word "approved". PANEL STATEMENT: Transformer vaults are not normally identified. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3523) 14- 205 - (502-2(a)(1)): Accept in Part SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (1) Containing Liquid that Will Burn. Transformers and capacitors containing liquid that will burn shall be installed only in approved (identified) vaults complying with Sections 450-41 through 450-48, and, in addition, the following shall apply. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. PANEL STATEMENT: Proposal 14-204 is identical and addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1599) 14- 206 - (502-2(a)(2)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (2) Not Containing Liquid that Will Burn. Transformers and capacitors that do not contain a liquid that will burn shall be installed in vaults complying with Sections 450-41 through 450-48 or be approved (identified) as a complete assembly, including terminal connections for Class II locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires

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that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3524) 14- 207 - (502-2(a)(2)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (2) Not Containing Liquid that Will Burn. Transformers and capacitors that do not contain a liquid that will burn shall be installed in vaults complying with Sections 450-41 through 450-48 or be approved (identified) as a complete assembly, including terminal connections for Class II locations. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #CP1409) 14- 207a - (502-4): Accept SUBMITTER: CMP 14 RECOMMENDATION: Amend first sentence by replacing "and" with "or". Make this same change in first sentence of 503-3. SUBSTANTIATION: "And" makes Division 1 wiring requirements mandatory for Division 2. PANEL ACTION: Accept. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban COMMENT ON AFFIRMATIVE: ENGLER: Not all of the changes made it into the draft circulated with this ballot, vote is to affirm the text with all of the necessary changes made to it. JAGUNICH: See ballot for David Wechsler. WECHSLER: See my Comment on Affirmative Vote on Proposal 14-200a. ___________________ (Log #1600) 14- 208 - (502-4(a)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (a) Class II, Division 1. In Class II, Division 1 locations, threaded rigid metal conduit, or Type MI cable with termination

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fittings approved (identified) for the location shall be the wiring method employed. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3525) 14- 209 - (502-4(a)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (a) Class II, Division 1. In Class II, Division 1 locations, threaded rigid metal conduit, threaded steel intermediate metal conduit, or Type MI cable with termination fittings approved (identified) for the location shall be the wiring method employed. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #2997) 14- 210 - (502-4(a), Exception): Accept SUBMITTER: Michael P. Mennone, Rockbestos-Surprenant Cable Corp. RECOMMENDATION: Revise 502-4(a) exception to read as follows: Exception: In industrial establishments with restricted public access, where the conditions of maintenance and supervision ensure that only qualified persons will service the installation, Type MC cable, listed for use in Class II, Division 1 locations, with a gas/vaportight continuous corrugated aluminum metallic sheath, an overall jacket of suitable polymeric material, separate grounding conductors in accordance with Section 250-122, and provided with termination fittings listed for the application shall be permitted. SUBSTANTIATION: Type MC with a gas/vaportight continuous corrugated sheath is manufactured and listed with various (aluminum, stainless steel, copper) sheath materials. In response to the acceptance of this exception (which was to be added to the 1996 NEC), UL Standard No. 2225 entitled "Metal-Clad Cables and Cable-Sealing Fittings for Use in Hazardous (Classified) Locations" was developed to qualify Type MC cables for this specific use. Cables meeting these additional requirements would then be listed as Type MC-HL. Copper and stainless steel sheathed Type MC cables have the same ability as aluminum to meet the intent of this section and also possess the ability to meet all of the additional requirements stated in UL Standard No. 2225. It is our contention that these additional types of sheathed cables were overlooked in

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the original proposal. This capability does exist and should be recognized by the code. PANEL ACTION: Accept. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #CP1408) 14- 210a - (502-4(a)(1)): Accept SUBMITTER: CMP 14 RECOMMENDATION: Revise 502-4(a)(1) to read: "(1) Fittings and Boxes. Fittings and boxes shall be provided with threaded bosses for connection to conduit or cable terminations and shall be dust-tight. Fittings and boxes in which taps, joints, or terminal connections are made, or that are used in Group E locations, shall be identified for Class II locations." SUBSTANTIATION: To correlate with 502-4(b)(1). PANEL ACTION: Accept. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban COMMENT ON AFFIRMATIVE: JAGUNICH: See ballot for David Wechsler. ___________________ (Log #1601) 14- 211 - (502-4(a)(1)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise second sentence to read as follows: Fittings and boxes in which taps, joints, or terminal connections are made, or that are used in locations where dusts are of a combustible, electrically conductive nature, shall be approved (identified) for Class II locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3526) 14- 212 - (502-4(a)(1)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the second sentence to read as follows: "Fittings and boxes in which taps, joists, or terminal connections are made, or that are used in locations where dusts are of a combustible, electrically conductive nature, shall be approved (identified) for Class II locations." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept.

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PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1602) 14- 213 - (502-4(a)(2)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (2) Flexible Connections. Where necessary to employ flexible connections, dusttight flexible connectors, liquidtight flexible metal conduit with approved (identified) fittings, liquidtight flexible nonmetallic conduit with approved (identified) fittings, or flexible cord approved (identified)for extra-hard usage and provided with bushed fittings shall be used. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed" in all three places. PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #1603) 14- 214 - (502-4(a)(2)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise third sentence to read as follows: Where flexible connections are subject to oil or other corrosive conditions, the insulation of the conductors shall be of a type approved (identified) for the conditions or shall be protected by means of a suitable sheath. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the most appropriate word. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: See my Explanation of Negative Vote on Proposal 14-180. ___________________ (Log #3527) 14- 215 - (502-4(a)(2)): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the third sentence to read as follows: "Where flexible connections are subject to oil or other corrosive conditions, the insulation of the conductors shall be of a type

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approved (identified) for the condition or shall be protected by means of a suitable sheath." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the most appropriate word. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: See my Explanation of Negative Vote on Proposal 14-180. ___________________ (Log #1604) 14- 216 - (502-4(b)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (b) Class II, Division 2. In Class II, Division 2 locations, rigid metal conduit, intermediate metal conduit, electrical metallic tubing, dusttight wireways, Type MC or MI cable with approved (identified) termination fittings, Type PLTC in cable trays, Type ITC in cable trays, or Type MC, MI, or TC cable installed in ladder, ventilated trough, or ventilated channel cable trays in a single layer, with a space not less than the larger cable diameter between the two adjacent cables, shall be the wiring method employed. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #2134) 14- 217 - (502-4(b)): Reject Note: It was the action of the Technical Correlating Committee that this Proposal be referred to Code-Making Panel 16 for information, with respect to Code-Making Panel 16's Panel Action on Proposal 16-319. Code-Making Panel 14 shall retain jurisdiction regarding types of wiring methods permitted in hazardous locations. SUBMITTER: Kari Barrett, Chemical Manufacturers Assn. RECOMMENDATION: Add the underlined text into the existing paragraph as follows: (b) Class II, Division 2. In Class II, Division 2 locations, rigid metal conduit, intermediate metal conduit, electrical metallic tubing, dusttight wireways, Type MC or MI cable with approved termination fittings, Type PLTC in cable trays, Type ITC in cable trays, Types CATVP, CATVR, CATV, or CATVX in cable tray, or Type MC, MI, or TC cable installed in ladder, ventilated trough, or ventilated channel cable trays in a single layer, with a space not less than the larger cable diameter between the two adjacent cables, shall be the wiring method employed. SUBSTANTIATION: Type CATVP, CATVR, CATV, or CATVX coaxial cables, as described in Section 820-51, have the additional having fire-resistant characteristics similar to the requirements for other types of cables such as TC and ITC, which are currently permitted for Class II Division 2 locations. In addition they are suitable for installation in cable trays as permitted by Article 318.

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Coaxial cables are needed in modern industrial facilities for digital and video signal transmission. PANEL ACTION: Reject. PANEL STATEMENT: See Proposal 14-73. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: LAWRENCE: Panel action should have been "Accept in Part in Principle" with the removal of Type CATVX and the addition of support/protection requirements to correlate with the actions of Panel 16 on Proposal 16-318 to accept Types CATVP, CATVR, and CATV in Section 820-53(e). COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-73. ___________________ (Log #2851) 14- 218 - (502-4(b)): Reject SUBMITTER: Nicholas Ludlam, Factory Mutual Research RECOMMENDATION: Separation of Nonincendive Field Wiring Conductors (a) From Nonincendive Field Wiring Conductors. (1) Open Wiring. Conductors and cables of nonincendive field wiring circuits not in raceways or cable trays shall be separated at least 1.97 in. (50 mm) and secured from conductors and cables of any other circuits. (2) In Raceways, Cable Trays, and Cables. Conductors of nonincendive field wiring circuits shall not be placed in any raceway, cable tray, or cable with conductors of any other circuit. Exception No. 1: Where conductors of nonincendive field wiring circuits are separated from conductors of incendive field wiring circuits by a distance of at least 1.97 in. (50 mm) and secured, or by a grounded metal partition or an approved insulating partition. FPN: No. 20 gauge sheet metal partitions 0.0359 in. (912 µm) or thicker are generally considered acceptable. Exception No. 2: Where either (1) all of the nonincendive field wiring circuit conductors or (2) all of the incendive field wiring circuit conductors are in grounded metal-sheathed or metal-clad cables where the sheathing or cladding is capable of carrying fault current to ground. FPN: Cables meeting the requirements of Articles 330 and 334 are typical of those considered acceptable. (3) Within Enclosures. a. Conductors of nonincendive field wiring circuits shall be separated at least 1.97 in. (50 mm) from conductors of any incendive field wiring circuits, or as specified in Section 5014(b)(a)(2). b. All conductors shall be secured so that any conductor that might come loose from a terminal cannot come in contact with another terminal. FPN No. 1: The use of separate wiring compartments for the nonincendive field wiring and incendive field wiring terminals is the preferred method of complying with this requirement. FPN No. 2: Physical barriers such as grounded metal partitions or approved insulating partitions or approved restricted access wiring ducts separated from other such ducts by at least in. (19 mm) can be used to help ensure the required separation of the wiring. (b) From Different Nonincendive Field Wiring Circuit Conductors. Different nonincendive field wiring circuits shall be in separate cables or shall be separated from each other by one of the following means. 1. The conductors of each circuit are within a grounded metal shield. 2. The conductors of each circuit have insulation with a minimum thickness of 0.01 in. (254 µm). Exception: Unless otherwise approved. SUBSTANTIATION: Apart from the exception in 501-4(b) the current version of the Code does not give any guidance on wiring for nonincendive field wiring circuits. An examination of nonincendive field wiring takes into consideration the faults of opening, shorting, and grounding of the field wiring. When applied to multiple conductor applications such as programmable logic controllers [PLCs] this type of approach can lead to output parameters for the devices which render them unusable. The current version of the Code requires the examination to include situations which, cannot be determined by the manufacturer of the

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equipment or an NRTL. The installer could determine these parameters but how many would actually consider these in the case where multiple nonincendive circuits are run in a single cable. The situation is similar to that for intrinsically safe wiring, and the proposed text is based on that in Article 504-30. PANEL ACTION: Reject. PANEL STATEMENT: See Proposal 14-84. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3528) 14- 219 - (502-4(b)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (b) Class II, Division 2. In Class II, Division 2 locations, rigid metal conduit, intermediate metal conduit, electrical metallic tubing, dusttight wireways, Type MC or MI cable with approved (identified) termination fittings, Type PLTC in cable trays, Type ITC in cable trays, or Type MC, MI, or TC cable installed in ladder, ventilated trough, or ventilated channel cable trays in a single layer, with a space not less than the larger cable diameter between the two adjacent cables, shall be the wiring method employed. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #4239) 14- 220 - (502-4(b), Exception): Accept in Principle SUBMITTER: Frederic P. Hartwell, Hartwell Electrical Services, Inc. RECOMMENDATION: Revise by deleting the word "ordinary" and replacing it with the word "unclassified." SUBSTANTIATION: This is the technically correct term. This was proposal 14-208 in the prior cycle, one of four proposals that the panel accepted in the ROP, forgot about, and inadvertently wiped out through unrelated editorial activity in the comment period. PANEL ACTION: Accept in Principle. The definition of "ordinary" has been modified to "nonhazardous". See Proposal 14-2a. In Exception No. 1 to 502-4(b), after the word "locations", add the words "including Chapter 7 and 8 wiring methods." PANEL STATEMENT: Proposal 14-2a addresses this issue. The added words correlate with Article 501 requirements. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: The panel action should be "Accept". See my comments on Proposal 14-2a. GOODMAN: The proposal should be "Accept" and not "Accept in Principle". The Panel Action is contrary to the submitter's intent and justification with respect to the term "Unclassified" as a replacement for "Nonhazardous". The correct term is "unclassified". Also see detailed comment under Proposal 14-2a. ___________________

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(Log #2389) 14- 221 - (502-4(b)(1)): Accept Note: It was the action of the Technical Correlating Committee that this Proposal be reconsidered and correlated with the action on Proposal 14-222. This action will be considered by the Panel as a Public Comment. SUBMITTER: William E. Bickner, Stillwater, MN RECOMMENDATION: Revise the heading and first sentence as shown below: (1) Wireways, Fittings, and Boxes. Wireways, fF ittings, and boxes in which taps. (balance unchanged) SUBSTANTIATION: 502-4(b) requires dusttight wireways in Class II, Division 2. Present wording of (1) conflicts with that requirement by permitting wireways "designed to minimize the entrance of dust," which are not necessarily dusttight under the Article 100 definition of that term. PANEL ACTION: Accept. PANEL STATEMENT: See Proposal 14-222. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #2390) 14- 222 - (502-4(b)(1)): Accept in Principle SUBMITTER: William E. Bickner, Stillwater, MN RECOMMENDATION: Revise as shown below: (1) Wireways, Fittings, and Boxes. Wireways, fittings, and boxes in which taps, joints, or terminal connections are made shall be designed to minimize the entrance of dust. (balance unchanged) SUBSTANTIATION: A Class II location can be extremely dusty without being Division 1, resulting in dust buildup within enclosures that do not adequately minimize the entrance of dust. The present language does not address fittings and boxes without taps, joints, or terminal connections, and therefor permits standard stamped metal boxes and covers with multiple KO punchings and numerous small holes. This is inconsistent with Section 502-4(b), which requires dusttight wireways in Class II, Division 2, and Section 503-3(a) and (b), which require dusttight boxes and fittings in Class III locations, without regard to taps, joints, or terminal fittings. PANEL ACTION: Accept in Principle. Revise 502-4(b)(1) to read: "(1) Boxes and Fittings. All boxes and fittings shall be dust-tight." PANEL STATEMENT: This more effectively meets the intent of the submitter. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1605) 14- 223 - (502-6(a)(1)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (1) Type Required. Switches, circuit breakers, motor controllers, and fuses, including pushbuttons, relays, and similar devices that are intended to interrupt current during normal operation or that are installed where combustible dusts of an electrically conductive nature may be present, shall be provided with approved (identified) dust-ignitionproof enclosures. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION:

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AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3529) 14- 224 - (502-6(a)(1)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (1) Type Required. Switches, circuit breakers, motor controllers, and fuses, including pushbuttons, relays, and similar devices that are intended to interrupt current during normal operation or that are installed where combustible dusts of an electrically conductive nature may be present, shall be provided with approved (identified) dust-ignitionproof enclosures. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1606) 14- 225 - (502-6(a)(3)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (3) Metal Dusts. In locations where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present, fuses, switches, motor controllers, and circuit breakers shall have enclosures specifically approved (identified) for such locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Replace "approved" with "identified" and delete the word "specifically". PANEL STATEMENT: This word implies a higher level of identification which is not intended by Panel 14. Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________

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(Log #3530) 14- 226 - (502-6(a)(3)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (3) Metal Dusts. In locations where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present, fuses, switches, motor controllers, and circuit breakers shall have enclosures specifically approved (identified) for such locations. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Replace "approved" with "identified" and delete the word "specifically". PANEL STATEMENT: This word implies a higher level of identification which is not intended by Panel 14. Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1607) 14- 227 - (502-7(a)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise second sentence to read as follows: No control transformer, impedance coil, or resistor shall be installed in a location where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present unless provided with an enclosure approved (identified) for the specific location. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3531) 14- 228 - (502-7(a)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the second sentence to read as follows: "No control transformer, impedance coil, or resistor shall be installed in a location where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present unless provided with an enclosure approved (identified) for the specific location." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific

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purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1608) 14- 229 - (502-7(b)(3)): Accept Note: The Technical Correlating Committee understands that the Exception is to remain as currently written. SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (3) Resistors. Resistors and resistance devices shall have dustignitonproof enclosures approved (identified) for Class II locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3532) 14- 230 - (502-7(b)(3)): Accept Note: The Technical Correlating Committee understands that the Exception is to remain as currently written. SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (b) Resistors. Resistors and resistance devices shall have dustignitionproof enclosures approved (identified) for Class II locations. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Proposal 14-229 is identical and addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________

Copyright 2000, NFPA

(Log #1609) 14- 231 - (502-8(a)(1)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: Approved (identified) for Class II, Division 1 locations, or. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "Identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3533) 14- 232 - (502-8(a)(1)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (1) Approved (Identified) for Class II, Division 1 locations, or. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1610) 14- 233 - (502-10(a)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (a) Class II, Division 1. In Class II, Division 1 locations, all utilization equipment shall be approved (identified) for Class II locations. Where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present, such equipment shall be approved (identified) for the specific location. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban

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EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3534) 14- 234 - (502-10(a)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (a) Class II, Division 1. In Class II, Division 1 locations, all utilization equipment shall be approved (identified) for Class II locations. Where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present, such equipment shall be approved (identified) for the specific location. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1959) 14- 235 - (502-10(b)(1)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise as follows: (1) Heaters. Electrically heated utilization equipment shall be approved (identified) for Class II locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3535) 14- 236 - (502-10(b)(1)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (1) Heaters. Electrically heated utilization equipment shall be approved (identified) for Class II locations. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based

Copyright 2000, NFPA

on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1958) 14- 237 - (502-11(a)(1)): Accept in Principle in Part SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise as follows: (1) Approved (Identified) Fixtures. Each fixture shall be approved (identified) for Class II locations and shall be clearly marked to indicate the maximum wattage of the lamp for which it is approved (identified). In locations where dusts from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present, fixtures for fixed or portable lighting and all auxiliary equipment shall be approved (identified) for the specific location. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle in Part. Delete the first "approved" in title. Replace second and fourth "approved" with "identified". Replace third "approved" with "designed". PANEL STATEMENT: "Approved" is not necessary in the title. In the third case, the word "designed" is more appropriate. Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3536) 14- 238 - (502-11(a)(1)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (1) Approved (Identified) Fixtures. Each fixture shall be approved (identified) for Class II locations and shall be clearly marked to indicate the maximum wattage of the lamp for which it is approved (identified). In locations where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present, fixtures for fixed or portable lighting and all auxiliary equipment shall be approved (identified) for the specific location. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-237 is identical and addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION:

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AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1955) 14- 239 - (502-11(a)(3)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise the fourth sentence as follows: Where wiring between an outlet box or fitting and a pendant fixture is not enclosed in conduit, flexible cord approved (identified) for hard usage shall be used, and suitable seals shall be provided where the cord enters the fixture and the outlet box or fitting. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed extra-hard and hard usage cord is readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: WECHSLER: See my Explanation of Negative Vote on Proposal 14-71. ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1956) 14- 240 - (502-11(a)(3)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise the second sentence to read as follows: For rigid stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of a fitting or a flexible connector approved (identified) for the location shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: WECHSLER: See my Explanation of Negative Vote on Proposal 14-71. ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1957) 14- 241 - (502-11(a)(3)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI

Copyright 2000, NFPA

RECOMMENDATION: Revise the first sentence to read as follows: (3) Pendant Fixtures. Pendant fixtures shall be suspended by threaded rigid metal conduit stems, threaded steel intermediate metal conduit stems, by chains with approved (identified) fittings, or by other approved (identified) means. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the appropriate word. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3537) 14- 242 - (502-11(a)(3)): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the first sentence to read as follows: (3) Pendant Fixtures. Pendant fixtures shall be suspended by threaded rigid metal conduit stems, threaded steel intermediate metal conduit stems, by chains with approved (identified) fittings, or by other approved (identified) means. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the appropriate word. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3538) 14- 243 - (502-11(a)(3)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the second sentence to read as follows: "For rigid stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of a fitting or a flexible connector approved (identified) for the location shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3539) 14- 244 - (502-11(a)(3)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors

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RECOMMENDATION: Revise the fourth sentence to read as follows: "Where wiring between an outlet box or fitting and a pendant fixture is not enclosed in conduit, flexible cord approved (identified) for hard usage shall be used, and suitable seals shall be provided where the cord enters the fixture and the outlet box or fitting. Flexible cord shall not serve as the supporting means for a fixture." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed extra-hard and hard usage cord is readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1954) 14- 245 - (502-11(a)(4)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise as follows: (4) Supports. Boxes, box assemblies, or fittings used for the support of lighting fixtures shall be approved (identified) for Class II locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3540) 14- 246 - (502-11(a)(4)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (4) Supports. Boxes, box assemblies, or fittings used for the support of lighting fixtures shall be approved (identified) for Class II locations. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION:

Copyright 2000, NFPA

AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1953) 14- 247 - (502-11(b)(1)): Accept in Principle in Part SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise as follows: (1) Portable Lighting Equipment. Portable lighting equipment shall be approved (identified) for Class II locations. They shall be clearly marked to indicate the maximum wattage of lamps for which they are approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle in Part. Replace the first "approved" with "identified"; replace the second "approved" with "designed". PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3541) 14- 248 - (502-11(b)(1)): Accept in Principle in Part SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (1) Portable Lighting Equipment. Portable lighting equipment shall be approved (identified) for Class II locations. They shall be clearly marked to indicate the maximum wattage of lamps for which they are approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle in Part. Replace the first "approved" with "identified"; replace the second "approved" with "designed". PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1952) 14- 249 - (502-11(b)(2)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise the first sentence to read as follows: (2) Fixed Lighting. Lighting fixtures for fixed lighting, where not of a type approved (identified) for Class II locations, shall provide enclosures for lamps and lampholders that shall be designed to minimize the deposit of dust on lamps and to prevent the escape of sparks, burning material, or hot metal.

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SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3542) 14- 250 - (502-11(b)(2)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the first sentence to read as follows: (2) Fixed Lighting. Lighting fixtures for fixed lighting, where not of a type approved (identified) for Class II locations, shall provide enclosures for lamps and lampholders that shall be designed to minimize the deposit of dust on lamps and to prevent the escape of sparks, burning material, or hot metal. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1949) 14- 251 - (502-11(b)(4)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise the third sentence as follows: Where wiring between an outlet box or fitting and a pendent fixture is not enclosed in conduit, flexible cord approved (identified) for hard usage shall be used. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed extra-hard and hard usage cord is readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE:

Copyright 2000, NFPA

WECHSLER: See my Explanation of Negative Vote on Proposal 14-71. ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1950) 14- 252 - (502-11(b)(4)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise the second sentence as follows: For rigid stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of an approved (identified) fitting or a flexible connector shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #1951) 14- 253 - (502-11(b)(4)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise the first sentence as follows: (4) Pendant Fixtures. Pendant fixtures shall be suspended by thread rigid metal conduit stems, threaded steel intermediate metal conduit stems, by chains with approved (identified) fittings, or by other approved (identified) means. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the appropriate word. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3543) 14- 254 - (502-11(b)(4)): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the first sentence to read as follows: (4) Pendant Fixtures. Pendant fixtures shall be suspended by thread rigid metal conduit stems, threaded steel intermediate metal conduit stems, by chains with approved (identified) fittings, or by other approved (identified) means. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction

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would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the appropriate word. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3544) 14- 255 - (502-11(b)(4)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the second sentence to read as follows: For rigid stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of an approved (identified) fitting or a flexible connector shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3545) 14- 256 - (502-11(b)(4)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the third sentence to read as follows: "Where wiring between an outlet box or fitting and a pendant fixture is not enclosed in conduit, flexible cord approved (identified) for hard usage shall be used. Flexible cord shall not serve as the supporting means for a fixture." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved' to "listed". PANEL STATEMENT: Listed extra-hard and hard usage cord is readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: WECHSLER: See my Explanation of Negative Vote on Proposal 14-71. ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #2387) 14- 257 - (502-12, Exception (New) ): Accept in Principle SUBMITTER: William E. Bickner, Stillwater, MN RECOMMENDATION: Add the following Exception: Exception: Flexible cord approved for hard usage shall be

Copyright 2000, NFPA

permitted between an outlet box or fitting and a pendant fixture, as provided by Sections 502-11(a)(3) and 502-11(b)(4). SUBSTANTIATION: The present requirement of this section for the use of extra-hard usage cord in Class II locations conflicts with those that permit hard-usage flexible cord for fixture pendants under Sections 502-11(a)(3) and 502-11(b)(4). PANEL ACTION: Accept in Principle. Add an exception to 502-12(1) to read: "Flexible cord listed for hard usage as permitted by Sections 502-11(a)(3) and (b)(4)." PANEL STATEMENT: The panel's version simplifies the langauge and inserts the exception in the correct location in code. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: WECHSLER: See my Explanation of Negative Vote on Proposal 14-71. ___________________ (Log #1948) 14- 258 - (502-12(1)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise as follows: (1) Be of a type approved (identified) for extra-hard usage,... SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed extra-hard and hard usage cord is readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: WECHSLER: See my Explanation of Negative Vote on Proposal 14-71. ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3546) 14- 259 - (502-12(1)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: "(1) Be of a type approved (identified) for extra-hard usage,". SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed extra-hard and hard usage cord is readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: WECHSLER: See my Explanation of Negative Vote on Proposal 14-71. ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1947) 14- 260 - (502-12(3)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI

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RECOMMENDATION: Revise as follows: (3) Be connected to terminals or to supply conductors in an approved (identified) manner,... SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3547) 14- 261 - (502-12(3)): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: "(3) Be connected to terminals or to supply conductors in an approved (identified) manner,". SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1611) 14- 262 - (502-13(a)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: In Class II, Division 1 locations, receptacles and attachment plugs shall be of the type providing for connection to the grounding conductor of the flexible cord and shall be approved (identified) for Class II locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________

Copyright 2000, NFPA

(Log #3548) 14- 263 - (502-13(a)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (a) Class II, Division 1. In Class II, Division 1 locations, receptacles and attachment plugs shall be of the type providing for connection to the grounding conductor of the flexible cord and shall be approved (identified) for Class II locations. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1612) 14- 264 - (502-14(a)(2)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: Switches, circuit breakers, relays, contactors, fuses and currentbreaking contacts for bells, horns, howlers, sirens, and other devices in which sparks or arcs may be produced shall be provided with enclosures approved (identified) for a Class II location. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3549) 14- 265 - (502-14(a)(2)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: "Switches, circuit breakers, relays, contactors, fuses and currentbreaking contacts for bells, horns, howlers, sirens, and other devices in which sparks or arcs may be produced shall be provided with enclosures approved (identified) for Class II location." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a.

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NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1613) 14- 266 - (502-14(a)(3)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise first paragraph to read as follows: Resisters, transformers, choke coils, rectifiers, thermionic tubes, and other heat-generating equipment shall be provided with enclosures approved (identified) for Class II locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3550) 14- 267 - (502-14(a)(3)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the first paragraph to read as follows: "Resistors, transformers, choke coils, rectifiers, thermionic tubes, and other heat-generating equipment shall be provided with enclosures approved (identified) for Class II locations." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1614) 14- 268 - (502-14(a)(5)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: Where dusts are of a combustible, electrically conductive nature, all wiring and equipment shall be approved (identified) for Class II locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires

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that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3551) 14- 269 - (502-14(a)(5)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: "Where dusts are of a combustible, electrically conductive nature, all wiring and equipment shall be approved (identified) for Class II locations." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1615) 14- 270 - (502-14(a)(6)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (6) Metal Dusts. Where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present, all apparatus and equipment shall be approved (identified) for the specific conditions. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________

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(Log #3552) 14- 271 - (502-14(a)(6)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (6) Metal Dusts. Where dust from magnesium, aluminum, aluminum bronze powders, or other metals of similarly hazardous characteristics may be present, all apparatus and equipment shall be approved (identified) for the specific location. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1616) 14- 272 - (502-16(a)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: The locknut-bushing and double-locknut types of contact shall not be depended on for bonding purposes, but bonding jumpers with proper fittings or other approved (identified) means of bonding shall be used. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #2388) 14- 273 - (502-16(a)): Reject Note: It was the action of the Technical Correlating Committee that this Proposal be referred to Code-Making Panel 5 for information. SUBMITTER: William E. Bickner, Stillwater, MN RECOMMENDATION: Revise as shown below: (a) Bonding. Standard locknuts or bushings The locknutbushing, and double-locknut types of contacts shall not be depended on for bonding purposes, but bonding jumpers with proper fittings or other approved means of bonding shall be used; bonding shall comply with Sections 250-100 and 250-94. (Balance of paragraph and exception unchanged) FPN: See Section 250-100 for additional bonding requirements in hazardous (classified) locations. SUBSTANTIATION: Present wording conflicts with Section 25094, which is referenced by Section 250-100. Taken literally, it does not require bonding for standard locknuts that are employed to secure threadless connectors to enclosures, nor around concentric or eccentric knockouts that may not be suitable for bonding, as required under Section 250-94. May also be interpreted to prohibit the use of bonding locknuts and bushings, which are acceptable under Section 250-94. (The balance of this paragraph and the exception are also unnecessary if submitter's proposal for Section 250-100 is accepted).

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PANEL ACTION: Reject. PANEL STATEMENT: These requirements are more stringent than those in Article 250. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: See my Explanation of Negative Vote on Proposal 14-191. ___________________ (Log #3553) 14- 274 - (502-16(a)): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the first sentence to read as follows: "The locknut bushing and double-locknut types of contact shall not be depended on for bonding purposes, but bonding jumpers with proper fittings or other approved (identified) means of bonding shall be used." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________

ARTICLE 503 -- CLASS III LOCATIONS

(Log #1261) 14- 275 - (503): Reject Note: It was the action of the Technical Correlating Committee that this Proposal be reconsidered by the Panel. The issues of raceway trade size, extracts, and use of soft versus hard metrication were all studied in detail and resolutions were communicated to the Panel prior to the Panel Meeting. It should be noted that all of the other Code-Making Panels accepted the metrication directive. This action will be considered by the Panel as a Public Comment. SUBMITTER: Technical Correlating Committee National Electrical Code RECOMMENDATION: In 503-7, change "0.021 in. (533 µm)" to "0.53 mm (0.021 in.)". In 503-9(c), change "12 in. (305 mm)" to "300 mm (12 in.)" in three places. In 503-16(b), Exception (a), change "6 ft (1.83 m)" to "1.8 m (6 ft)". SUBSTANTIATION: The proposed revision complies with the NFPA 1M Manual of Style Section 4-1 with respect to the placement of units, i.e., to show the SI units as the preferred unit and the inch-pound units immediately following in parenthesis. PANEL ACTION: Reject. PANEL STATEMENT: Panel 14 believes the following issues need further evaluation before changes are made to the code: trade sizes of conduit; extract policies; consistency from article to article within the code. For example, trade size of conduit is not a true dimension and cannot be converted to a true metric number. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 9 NEGATIVE: 3 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: KUCZKA: See my Explanation of Negative Vote on Proposal 1410. OMEARA: The proposal should be accepted, to be in conformance with Chapter 4 of the NFPA MOS-1 Manual of Style. ZIPSE: See my Explanation of Negative Vote on Proposal 14-10. ___________________

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(Log #1617) 14- 276 - (503-3(a)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (a) Class III, Division 1. In Class III, Division 1 locations, the wiring method shall be rigid metal conduit, rigid nonmetallic conduit, intermediate metal conduit, electrical metallic tubing, dusttight wireways, or Type MC or MI cable with approved (identified) termination fittings. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3554) 14- 277 - (503-3(a)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (a) Class III, Division 1. In Class III, Division 1 locations, the wiring method shall be rigid metal conduit, rigid nonmetallic conduit, intermediate metal conduit, electrical metallic tubing, dusttight wireways, or Type MC or MI cable with approved (identified) termination fittings. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1618) 14- 278 - (503-3(a)(2)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: Where necessary to employ flexible connections, dusttight flexible connectors, liquidtight flexible metal conduit with approved (identified) fittings, liquidtight flexible nonmetallic conduit with approved (identified) fittings, or flexible cord in conformance with Section 503-10 shall be used. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed".

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PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3555) 14- 279 - (503-3(a)(2)): Accept in Principle NOTE: The Technical Correlating Committee understands that the word "liquidtight" was inadventently omitted from the second line in the Recommendation. SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: "Where necessary to employ flexible connections, dusttight flexible connectors, liquidtight flexible metal conduit with approved (identified) fittings, or flexible nonmetallic conduit with approved (identified) fittings, or flexible cord in conformance with Section 503-10 shall be used." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed fittings are readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #2852) 14- 280 - (503-3(b)): Reject SUBMITTER: Nicholas Ludlam, Factory Mutual Research RECOMMENDATION: Revise as follows: Exception No 2: Nonincendive field wiring shall be permitted using any of the methods suitable for wiring in ordinary locations. Separation of Nonincendive Field Wiring Conductors (a) From Nonincendive Field Wiring Conductors. (3) Open Wiring. Conductors and cables of nonincendive field wiring circuits not in raceways or cable trays shall be separated at least 1.97 in. (50 mm) and secured from conductors and cables of any other wiring. Exception: Where either (1) all of the nonincendive field wiring circuit conductors are in Type MI or MC cables or (2) all of the other circuit conductors are in raceways or Type MI or MC cables where the sheathing or cladding is capable of carrying fault current to ground. (4) In Raceways, Cable Trays, and Cables. Conductors of nonincendive field wiring circuits shall not be placed in any raceway, cable tray, or cable with conductors of any other wiring. Exception No. 1: Where conductors of nonincendive field wiring circuits are separated from conductors of incendive field wiring circuits by a distance of at least 1.97 in. (50 mm) and secured, or by a grounded metal partition or an approved insulating partition. FPN: No. 20 gauge sheet metal partitions 0.0359 in. (912 µm) or thicker are generally considered acceptable. Exception No. 2: Where either (1) all of the nonincendive field wiring circuit conductors or (2) all of the other wiring conductors are in grounded metal-sheathed or metal-clad cables where the sheathing or cladding is capable of carrying fault current to ground. FPN: Cables meeting the requirements of Articles 330 and 334 are typical of those considered acceptable. (3) Within Enclosures. a.) Conductors of nonincendive field wiring circuits shall be

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separated at least 1.97 in. (50 mm) from conductors of any other field wiring, or as specified in Section 503-(?)(a)(2). b.) All conductors shall be secured so that any conductor that might come loose from a terminal cannot come in contact with another terminal. FPN No. 1: The use of separate wiring compartments for the nonincendive field wiring and other field wiring terminals is the preferred method of complying with this requirement. FPN No. 2: Physical barriers such as grounded metal partitions or approved insulating partitions or approved restricted access wiring ducts separated from other such ducts by at least in. (19 mm) can be used to help ensure the required separation of the wiring. (b) From Different Nonincendive Field Wiring Circuit Conductors. Different nonincendive field wiring circuits shall be in separate cables or shall be separated from each other by one of the following means. 1. The conductors of each circuit are within a grounded metal shield. 2. The conductors of each circuit have insulation with a minimum thickness of 0.01 in. (254 µm). Exception: Unless otherwise approved. SUBSTANTIATION: Apart from the exception in 501-4(b) the current version of the Code does not give any guidance on wiring for nonincendive field wiring circuits. An examination of nonincendive field wiring takes into consideration the faults of opening, shorting, and grounding of the field wiring. When applied to multiple conductor applications such as programmable logic controllers [PLCs] this type of approach can lead to output parameters for the devices which render them unusable. The current version of the Code requires the examination to include situations which, cannot be determined by the manufacturer of the equipment or an NRTL. The installer could determine these parameters but how many would actually consider these in the case where multiple nonincendive circuits are run in a single cable. The situation is similar to that for intrinsically safe wiring, and the proposed text is based on that in Article 504-30. ANSI/ISA S12.12:1994 has requirements which make no distinction between Class. PANEL ACTION: Reject. PANEL STATEMENT: The panel believes that there is no technical justification given for separatiion of conductors above what is required in nonhazardous locations. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1619) 14- 281 - (503-8(a)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (a) Heaters. Electrically heated utilization equipment shall be approved (identified) for Class III locations. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________

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(Log #3556) 14- 282 - (503-8(a)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (a) Heaters. Electrically heated utilization equipment shall be approved (identified) for Class III locations. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1620) 14- 283 - (503-9(c)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise second sentence to read as follows: For stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of an approved (identified) fitting or a flexible connector shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3557) 14- 284 - (503-9(c)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the second sentence to read as follows: "For stems longer than 12 in. (305 mm), permanent and effective bracing against lateral displacement shall be provided at a level not more than 12 in. (305 mm) above the lower end of the stem, or flexibility in the form of an approved (identified) fitting or a flexible connector shall be provided not more than 12 in. (305 mm) from the point of attachment to the supporting box or fitting." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction

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would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1621) 14- 285 - (503-10(1)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: Be of a type approved (identified) for extra-hard usage;. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed extra-hard and hard usage cord is readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: WECHSLER: See my Explanation of Negative Vote on Proposal 14-71. ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #3558) 14- 286 - (503-10(1)): Accept in Principle SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (1) Be of a type approved (identified) for extra-hard usage; SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Principle. Change "approved" to "listed". PANEL STATEMENT: Listed extra-hard and hard usage cord is readily available. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: WECHSLER: See my Explanation of Negative Vote on Proposal 14-71. ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1622) 14- 287 - (503-10(3)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: (3) Be connected to terminals or to supply conductors in an approved (identified) manner;. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires

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that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3559) 14- 288 - (503-10(3)): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: (3) Be connected to terminals or to supply conductors in an approved (identified) manner; SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #921) 14- 289 - (503-13(a)): Reject SUBMITTER: Dan Leaf, Palmdale, CA RECOMMENDATION: Revise to read as follows: (a) Power Supply. Power supply to contact conductors shall be electrically isolated from all other systems and ungrounded, and shall be equipped with an acceptable ground detector that will give an alarm... (remainder unchanged). SUBSTANTIATION: Editorial. "Isolated" while perhaps understood does not specifically mean ungrounded. Separately derived systems from isolating or isolated secondaries of transformers are required to be grounded by certain Code sections, and ungrounded by some sections. Sections 668-20(b) and 66821(a) for example clearly specify an ungrounded secondary, which is apparently the intent. PANEL ACTION: Reject. PANEL STATEMENT: The panel believes the present text is clear. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1794) 14- 290 - (503-14): Accept SUBMITTER: Noel Williams, Noel Williams Consulting RECOMMENDATION: Revise the second sentence to read as follows: "The rooms shall be constructed to prevent the entrance of ignitable amounts of flyings or lint and shall be well ventilated." SUBSTANTIATION: The present language is unclear as to what is to be prevented. Either the entrance or accumulation of ignitable amounts is probably intended but neither requirement is stated. PANEL ACTION: Accept. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________

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(Log #1623) 14- 291 - (503-16(a)): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise first sentence to read as follows: The locknut-bushing and double-locknut types of contacts shall not be depended on for bonding purposes, but bonding jumpers with proper fittings or other approved (identified) means of bonding shall be used. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #2391) 14- 292 - (503-16(a)): Reject Note: It was the action of the Technical Correlating Committee that this Proposal be referred to Code-Making Panel 5 for information. SUBMITTER: William E. Bickner, Stillwater, MN RECOMMENDATION: Revise as shown below: (a) Bonding. Standard locknuts or bushings The locknutbushing, and double-locknut types of contacts shall not be depended on for bonding purposes, but bonding jumpers with proper fittings or other approved means of bonding shall be used; bonding shall comply with Sections 250-100 and 250-94 . (Balance of paragraph and exception unchanged) FPN: See Section 250-100 for additional bonding requirements in hazardous (classified) locations. SUBSTANTIATION: Present wording conflicts with Section 25094, which is referenced by Section 250-100. Taken literally, it does not require bonding for standard locknuts that are employed to secure threadless connectors to enclosures, nor around concentric or eccentric knockouts that may not be suitable for bonding, as required under Section 250-94. May also be interpreted to prohibit the use of bonding locknuts and bushings, which are acceptable under Section 250-94. (The balance of this paragraph and the exception are also unnecessary if submitter's proposal for Section 250-100 is accepted). PANEL ACTION: Reject. PANEL STATEMENT: These requirements are more stringent than those in Article 250. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: See my Explanation of Negative Vote on Proposal 14-191. ___________________ (Log #3560) 14- 293 - (503-16(a)): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the first sentence to read as follows: "The locknut-bushing and double-locknut types of contacts shall not be depended on for bonding purposes, but bonding jumpers with proper fittings or other approved (identified) means of bonding shall be used." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject.

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PANEL STATEMENT: "Approved" is the correct word to describe the "means", "manner", or "methods" employed to accomplish something. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________

ARTICLE 504 -- INTRINSICALLY SAFE SYSTEMS

(Log #1262) 14- 294 - (504): Reject Note: It was the action of the Technical Correlating Committee that this Proposal be reconsidered by the Panel. The issues of raceway trade size, extracts, and use of soft versus hard metrication were all studied in detail and resolutions were communicated to the Panel prior to the Panel Meeting. It should be noted that all of the other Code-Making Panels accepted the metrication directive. This action will be considered by the Panel as a Public Comment. SUBMITTER: Technical Correlating Committee National Electrical Code RECOMMENDATION: In 504-30(a)(1), change "1.97 in. (50 mm)" to "50 mm (2 in.)". In 504-30(a)(2), Exception, change "1.97 in. (50 mm)" to 50 mm (2 in.)". In 504-30(a)(2), Exception, FPN, change "0.0359 in. (912 µm)" to "0.91 mm (0.0359 in.)". In 504-30(a)(3)(a), change "1.97 in. (50 mm)" to "50 mm (2 in.)". In 504-30(a)(3)(b), FPN No. 2, change "3/4 in. (19 mm)" to "19 mm (3/4 in.)". In 504-30(b)(2), change "0.01 in. (254 µm)" to "0.25 mm (0.01 in.)." In 504-80(b), change "25 ft (7.62 m)" to "7.5 m (25 ft)". SUBSTANTIATION: The proposed revision complies with the NFPA 1M Manual of Style Section 4-1 with respect to the placement of units, i.e., to show the SI units as the preferred unit and the inch-pound units immediately following in parenthesis. PANEL ACTION: Reject. PANEL STATEMENT: Panel 14 believes the following issues need further evaluation before changes are made to the code: trade sizes of conduit; extract policies; consistency from article to article within the code. For example, trade size of conduit is not a true dimension and cannot be converted to a true metric number. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 9 NEGATIVE: 3 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: KUCZKA: See my Explanation of Negative Vote on Proposal 1410. OMEARA: The proposal should be accepted, to be in conformance with Chapter 4 of the NFPA MOS-1 Manual of Style. ZIPSE: See my Explanation of Negative Vote on Proposal 14-10. ___________________ (Log #CP1406) 14- 294a - (504-2): Accept Note: It was the action of the Technical Correlating Committee that further consideration be given to the comments expressed in the voting. The Technical Correlating Committee further directs that the action on this Proposal be rewritten to comply with the NEC Style Manual, with respect to the use of mandatory language in Fine Print Notes. This action will be considered by the Panel as a Public Comment. SUBMITTER: CMP 14 RECOMMENDATION: Replace existing definition of "simple apparatus" with the following: "An electrical component or combination of components of simple construction with well-defined electrical parameters which does not generate more than 1.5 volt, 100 milliamps and 25 milliwatts, or a passive component which does not dissipate more than 1.3 watts and which is compatible with the intrinsic safety of the circuit in which it is used. FPN 1: The following apparatus are examples of simple apparatus: a) passive components, for example switches, junction boxes,

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resistance temperature devices and simple semiconductor devices such as LED's; b) sources of generated energy, for example thermocouples and photocells, which do not generate more than 1.5 V, 100 mA and 25 mW. FPN 2: Simple apparatus should conform to all relevant requirements of ANSI/UL913 but need not be listed. In particular, the following aspects should always be considered. a) simple apparatus should not achieve safety by the inclusion of voltage and/or current limiting and/or suppression devices; b) simple apparatus should not contain any means of increasing the available voltage or current, for example circuits for the generation of ancillary power supplies; c) when simple apparatus is located in the hazardous location, it should be temperature classified. When used in an intrinsically safe circuit within their normal rating and at a maximum ambient temperature of 40°C switches, plugs and sockets and terminals are allocated a T4 temperature classification for Class I Division 1 Group A, B, C, and D or Class I Zone 1 Group IIC applications. Where simple apparatus forms part of an apparatus containing other electrical circuits, the whole should be listed. FPN 3 - Sensors which utilise catalytic reaction or other electrochemical mechanisms are not normally simple apparatus. Specialist advice on their application should be sought." SUBSTANTIATION: The 1999 Edition of IEC 60079-11 defines simple apparatus as 3.11 simple apparatus An electrical component or combination of components of simple construction with well-defined electrical parameters which is compatible with the intrinsic safety of the circuit in which it is used. This is then amplified by the following clause. 5.4 Simple apparatus The following apparatus shall be considered to be simple apparatus: a) passive components, for example switches, junction boxes, resistors and simple semiconductor devices; b) sources of stored energy with well defined parameters, for example capacitors or inductors, whose values shall be considered when determining the overall safety of the system; c) sources of generated energy, for example thermocouples and photocells, which do not generate more than 1,5 V, 100 mA and 25 mW. Any inductance or capacitance present in these sources of energy shall be considered as in b). Simple apparatus shall conform to all relevant requirements of this standard but need not be certified and need not comply with clause 12. In particular, the following aspects shall always be considered. a) simple apparatus shall not achieve safety by the inclusion of voltage and/or current limiting and/or suppression devices; b) simple apparatus shall not contain any means of increasing the available voltage or current, for example circuits for the generation of ancillary power supplies; c) where it is necessary that the simple apparatus maintains the integrity of the isolation from 'earth' of the intrinsically-safe circuit, it shall be capable of withstanding the test voltage to earth in accordance with 6.4.12. Its terminals shall conform to 6.3.1; d) non metallic enclosures and enclosures containing light metals when located in the hazardous area shall conform to 7.3 and 8.1 of IEC 60079-0, 1998; e) when simple apparatus is located in the hazardous area, it shall be temperature classified. When used in an intrinsically safe circuit within their normal rating and at a maximum ambient temperature of 40°C switches, plugs and sockets and terminals are allocated a T6 temperature classification for Group II applications and considered as having a maximum surface temperature of 85°C for Group I applications. Other types of simple apparatus shall be temperature classified in accordance with clauses 4 and 6 of this standard. Where simple apparatus forms part of an apparatus containing other electrical circuits, the whole shall be certified. NOTE - Sensors which utilize catalytic reaction or other electrochemical mechanisms are not normally simple apparatus. Specialist advice on their application should be sought. In the past, no technical justification has been available from the IEC for the change from the previous definition of 1.3 volts, 0.1 ampere, 25 milliwatts, or 20 microjoules. [I don't know why there is the difference between the US (1.2V) and IEC (1.3V) voltages] The original choice of 1.2 V was, I believe, made in the UK in the 1960's. It was possibly chosen because it was 10% of the 12 volt threshold voltage of hydrogen and unlikely to cause a serious degradation of the safety of an intrinsically safe circuit. The 1.3 V was introduced by CENELEC in 1977 with the publication of the 1st

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edition of EN50020. A proposal was accepted for the 1994 2nd edition of EN 50020 to change the parameters for simple apparatus. The arguments in favor of changing the definition are that the 1.2 volt limit excludes the use of some silicon solar cells and the possibility of using two silicon diodes in series to suppress the output from a circuit. This combination is frequently used to create apparatus, which although certified has input parameters equivalent to simple apparatus. The relaxation permits some single cell batteries theoretically but the 25mW/100mA restriction confines the available choice to a very restricted few. The original 20 mJ requirement is difficult to defend. Adding 20 mJ to a Group A, B circuit, which may be already near its limits, could remove the safety factor of 1.5; yet it is arguably restrictive in Class I Group C, D. It seems reasonable to take into account the known capacitance and inductance since this adequately ensures safety and is accepted practice for cables. If it is retained, the 20 mJ should have an associated time. A thermocouple producing 10 mV and 1 mA generates 20 microjoules in 2 seconds and hence is excluded by this requirement. 25 mW requires 800 mS and 100 mA and 1.2 V 167 mS. PANEL ACTION: Accept. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban COMMENT ON AFFIRMATIVE: COOK: I agree with the definition, but have concerns about FPN 2 and FPN 3. FPN 2 contains information that borders on being requirements which are prohibited from being located in a FPN. The second sentence in FPN 3 causes me great concern. As an authority having jurisdiction, I am not sure who would qualify as a specialist, and I am not sure about equipment that I need to seek a specialist for its application. JAGUNICH: See ballot for David Wechsler. ___________________ (Log #3564) 14- 295 - (504-2): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the third paragraph to read as follows: "Different intrinsically safe circuits are intrinsically safe circuits in which the possible interconnections have not been evaluated and approved (identified) as intrinsically safe." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #2528) 14- 296 - (504-2-Control Drawing): Reject Note: It was the action of the Technical Correlating Committee that this Proposal be referred to Code-Making Panel 1 for information. Companion Proposal 1-121 was rejected by CodeMaking Panel 1. SUBMITTER: Nicholas Ludlam, Factory Mutual Research RECOMMENDATION: Control Drawing. A drawing or other document provided by the manufacturer of the intrinsically safe or associated apparatus that details the allowed interconnections between the intrinsically safe and associated apparatus.

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SUBSTANTIATION: Move to Article 100, and modify this definition to allow the term Control Drawing to be used with both intrinsic safety and nonincendive field wiring. PANEL ACTION: Reject. PANEL STATEMENT: There is no proposed action. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1624) 14- 297 - (504-2-Different Intrinsically Safe Circuits): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise third paragraph to read as follows: Different intrinsically safe circuits are intrinsically safe circuits in which the possible interconnections have not been evaluated and approved (identified) as intrinsically safe. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3235) 14- 298 - (504-2-Intrinsically Safe Circuit): Reject SUBMITTER: Sukanta Sengupta, FMC Corp. RECOMMENDATION: Add a new paragraph after the first paragraph. "For Class I and II, Division 2 locations nonincendive circuits are same as intrinsically safe circuits." SUBSTANTIATION: Insrinsically safe circuits and nonincendive circuits are tested in the same manner in normal conditions(Division 2 conditions). PANEL ACTION: Reject. PANEL STATEMENT: The submitter's proposal and substantiation is incorrect. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1540) 14- 299 - (504-2-Simple Apparatus): Reject SUBMITTER: Thomas J. Conlan, Conlan's "The Electrician Inc." RECOMMENDATION: Revise to read as follows: Simple Apparatus. A device that will neither generator nor store more than 1.2 volts, 0.1 ampere, 25 milliwatts or 20 micro joules. SUBSTANTIATION: Volts times amps = watts Change to = A device that will neither generate nor store more than 1.2 volts AC/DC, 0.1 ampere, 12 milliwatts or 20 micro joules. PANEL ACTION: Reject. PANEL STATEMENT: The submitter's proposal and substantiation is incorrect. The energy values are not the product of the voltage and the current limits. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION:

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AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1625) 14- 300 - (504-4): Accept Note: The Technical Correlating Committee understands that the Exception will remain as currently written. SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: 504-4. Equipment Approval. All intrinsically safe apparatus and associated apparatus shall be approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3565) 14- 301 - (504-4): Accept Note: The Technical Correlating Committee understands that the Exception will remain as currently written. SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise text to read as follows: 504-4. Equipment Approval. All intrinsically safe apparatus and associated apparatus shall be approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1946) 14- 302 - (504-4, Exception): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL RECOMMENDATION: Revise to read as follows: Exception: Simple apparatus, as described on the control drawing, shall not be required to be approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose.

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PANEL ACTION: Accept in Principle. Use the word "listed" instead of identified. PANEL STATEMENT: "Approved" is not the correct word to be used in this context. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: This proposal was made in a hurry along with the 150 + -- proposals dealing with the term "approved". I believe that the proposal should be rejected and that Proposal 14-303 should be accepted. I do not believe that a Code suitable for adoption will usurp that jurisdiction's authority to establish criteria for acceptability of equipment. ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3991) 14- 303 - (504-4, Exception): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL RECOMMENDATION: Delete Section 504-4 Exception: Exception: Simple apparatus, as described on control drawing, shall not be required to be approved. SUBSTANTIATION: Based on Section 110-2 of the NEC, which requires all equipment required or permitted by the NEC to be approved, and the fact that this document is intended for adoption in laws that would be enforced by authorities having jurisdiction, it does not seem acceptable to have a rule that denies the authority having jurisdiction the ability to determine the acceptability of equipment. PANEL ACTION: Reject. PANEL STATEMENT: See Panel action on Proposal 14-302. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: I disagree with the Panel Action . See substantiation and my negative comment on Proposal 14-302. ___________________ (Log #401) 14- 304 - (504-10(b)): Reject SUBMITTER: John Strelow, Oseco, Inc. RECOMMENDATION: Add the following paragraph to 504-10(b): Simple apparatus shall be permitted to be installed in hazardous (classified) locations only if installed in intrinsically safe circuits. SUBSTANTIATION: We make a simple apparatus (burst disk alarm sensor) and this issue has come up several times. (Can a simple apparatus be installed in a hazardous location?). PANEL ACTION: Reject. PANEL STATEMENT: Article 504 covers intrinsically safe circuits and does not need to be repeated here. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #1626) 14- 305 - (504-10(b)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise first sentence to read as follows: Intrinsically safe apparatus shall be permitted to be installed in any hazardous (classified) locations for which it has been approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction

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would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #1627) 14- 306 - (504-10(b)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise second paragraph to read as follows: Associated apparatus shall be permitted to be installed in any hazardous (classified) location for which it has been approved (identified), or if protected by other means permitted by Articles 501 through 503 and 505. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3566) 14- 307 - (504-10(b)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the first sentence to read as follows: "Intrinsically safe apparatus shall be permitted to be installed in any hazardous (classified) locations for which it has been approved (identified)." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________

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(Log #3567) 14- 308 - (504-10(b)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the second paragraph to read as follows: "Associated apparatus shall be permitted to be installed in any hazardous (classified) location for which it has been approved (identified), or if protected by other means permitted by Articles 501 through 503 and 505." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1945) 14- 309 - (504-30(2) Exception No. 1): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise as follows: Exception No. 1: Where conductors of intrinsically safe circuits are separated from conductors of nonintrinsically safe circuits by a distance of at least 1.97 in. (50 mm) and secured, or by a grounded metal partition or an approved (identified) insulating partition. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the appropriate word to use in this context. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: I disagree with both the proposal and the Panel Action. I agree that an insulating partition would not be identified, however the term "approved" should be deleted. Partitions are not means, methods or manners that need some special attention. I do not believe any additional approval, other than required by 1102, is needed. ___________________ (Log #3561) 14- 310 - (504-30(a)(2) Exception No. 1): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the Exception to read as follows: Exception No. 1: Where conductors of intrinsically safe circuits are separated from conductors of nonintrinsically safe circuits by a distance of at least 1.97 in. (50 mm) and secured, or by a grounded metal partition or an approved (identified) insulating partition. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject.

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PANEL STATEMENT: "Approved" is the appropriate word to use in this context. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: See my Explanation of Negative Vote on Proposal 14-309. ___________________ (Log #1944) 14- 311 - (504-30(a)(3)(b), FPN No. 2): Reject SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise to read as follows: FPN No. 2: Physical barriers such as grounded metal partions or approved (identified) insulating partitions or approved (identified) restricted access wiring ducts separated from other such ducts by at least 3/4 in. (19 mm) can be used to help ensure the required separation of the wiring. SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the appropriate word to use in this context. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: See negative comment on Proposal 14-310 for partitions. Restricted access wiring ducts are certainly identified and available with listings from many manufacturers under category (ZOYX) in the UL Green Book. ___________________ (Log #3562) 14- 312 - (504-30(a)(3)(b), FPN No. 2): Reject SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the fine print note to read as follows: FPN No. 2: Physical barriers such as grounded metal partitions or approved (identified) insulating partitions or approved (identified) restricted access wiring ducts separated from other such ducts by at least 3/4 in. (19 mm) can be used to help ensure the required separation of the wiring. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Reject. PANEL STATEMENT: "Approved" is the appropriate word to use in this context. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: See my Explanation of Negative Vote on Proposal 14311. ___________________

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(Log #1943) 14- 313 - (504-30(b), Exception): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise as follows: Exception: Unless otherwise approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3563) 14- 314 - (504-30(b), Exception): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the Exception to read as follows: Exception: Unless otherwise approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #922) 14- 315 - (504-60(b)): Accept in Principle in Part SUBMITTER: Dan Leaf, Palmdale, CA RECOMMENDATION: Revise to read as follows: (b) Nonhazardous unclassified locations in unclassified nonhazardous locations where metal raceways, cables, cable trays, or auxiliary gutters are used for intrinsically safe system wiring and extended into hazardous (classified) locations associated apparatus shall be bonded bonding shall be in accordance with sections 50116(a); 502-16(a); 503-16(a); or 505-25 as applicable. SUBSTANTIATION: The proposal is intended for clarification of intent. Nonhazardous and hazardous are not specific per code intent and can literally apply to locations not related to classified or unclassified locations. Bonding should not be limited to raceways and apparatus which is not defined. PANEL ACTION: Accept in Principle in Part. Revise 504-60(b) to read: "(b) Unclassified or Nonhazardous Locations. In unclassified or nonhazardous locations . . .hazardous (classified) locations . . ." PANEL STATEMENT: This implements the new definitions accepted under Proposal 14-352. The additional text was not accepted because cable trays and auxiliary gutters are covered elsewhere in the code and cables do not require bonding. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14

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VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: The panel action should be "Accept in Part". See my comments on Proposal 14-2a for use of the term "unclassified." GOODMAN: This proposal should be "Accept in Part" and not "Accept in Principle in Part". The Panel Action is contrary to the submitter's intent and justification with respect to the term "Unclassified" as a replacement for "Nonhazardous". The correct term is "unclassified". Also see detailed comments under Proposal 14-2a. ___________________ (Log #2135) 14- 316 - (504-60(b)): Accept in Principle in Part SUBMITTER: Kari Barrett, Chemical Manufacturers Assn. RECOMMENDATION: Replace "nonhazardous" with "unclassified" in 2 places. SUBSTANTIATION: This is a companion to other proposals which provide a definition of unclassified in Articles 100, 500, and 505, and provides correlation. The term "Classified" refers to the type of material/hazard potential involved, i.e., Class I, Division 1, Class II, Division 2, etc. Terms such as nonhazardous and unclassified are used in both the NEC, the Uniform Building Code (UBC) and other NFPA documents. The term nonhazardous infers that the area has "no" hazards while the term "unclassified" more clearly correlates with the condition of being reviewed but found not to need classification. This action provides needed correlation with other NFPA documents, such as NFPA 497. Additionally the term "nonhazardous" is used 7 times within various parts of the NEC and in at least one place in the NEC the meaning of nonhazardous applies to voltages and not classification. A companion proposal has been made to change the term "nonhazardous" to "unclassified" as appropriate elsewhere in the NEC. PANEL ACTION: Accept in Principle in Part. PANEL STATEMENT: The action on Proposal 14-315 addresses these issues. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: The panel action should be "Accept". See my comments on Proposal 14-2a. GOODMAN: This proposal should be "Accept" and not "Accept in Principle". The Panel Action is contrary to the submitter's intent and justification with respect to the use of the terms "Unclassified" and "Nonhazardous". This proposal along with the other companion proposals referenced in the submitter's substantiation are designed to remove the term "nonhazardous" from the NEC, not add and define the term. Also see additional comments under Proposal 14-318a. ___________________ (Log #2392) 14- 317 - (504-80(b)): Reject SUBMITTER: William E. Bickner, Stillwater, MN RECOMMENDATION: Revise as shown below: (b) Wiring. Raceways, cable trays, and open wiring cables. (balance unchanged) SUBSTANTIATION: "Open wiring" (unless the intent is open wiring on insulators) is not one of the wiring methods "suitable for unclassified locations" which Section 504-20 requires to be used for intrinsically safe circuits. "Cables" seems more appropriate. PANEL ACTION: Reject. PANEL STATEMENT: The panel believes that 504-30(a)(1) allows cables to be run as open wiring. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: I agree with the submitter's proposal and substantiation. ___________________

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(Log #4014) 14- 318 - (504-80(b)): Reject SUBMITTER: Christopher Pharo, Rep. IBEW RECOMMENDATION: This proposal is to revise part (b) to read as follows: Article 504-80(b) Wiring. Raceways, cable trays, and open wiring for intrinsically safe system wiring shall be identified with permanently affixed labels with the wording "WARNING -Instrinsic Safe Wiring- Keep all wiring methods 2 in. away ". The labels shall be so located so as to be visible after installation and placed so that they may be readily traced through the entire length of the installation. Spacing between labels shall not be more than 10 ft. SUBSTANTIATION: There is never a problem installing an intrinsic safe system initially. However, chances are, the next electrician, data technician, maintenance worker, or telephone technician will not know what an intrinsic safe system is. With this in mind, it would be reasonable to expect these people would not be aware of any special requirements that this system is subject to. Previous code panels have amended certain warning signs to include some type of command as well as a warning or danger. A simple sign that reads as follows: "DANGER-HIGH VOLTAGE" was subsequently changed to "DANGER-HIGH VOLTAGE-KEEP OUT". An accident probably occurred in the above example and that is why a simple command is now included. The simple labeling of the cables in a intrinsically safe system is not adequate. The label should include some type of warning, some type of identification as to the hazard, and then finally some type of direction or command. Most workers would not be familiar enough with this wiring system to know that they have to stay at least 2 in. away with their own wiring method. A label identified as "WARNING-Intrinsic Safe Wiring-Keep all wiring methods 2 in. away" would meet this criteria. The distance of 25 ft is inadequate. When an installer or technician runs their cables above a drop ceiling, it is usually very dark. The distance that one can see above a dark drop veiling is limited, probably to no more than 10 ft. By placing a 10 ft maximum distance between labels, this would assure future installers of a possible hazard yet it would also aid them in their installation. I would think future installations in the areas around intrinsic safe wiring are difficult to police and would suggest that this type of labeling system may prevent confusion and limit liability. PANEL ACTION: Reject. PANEL STATEMENT: This is already addressed in 504-30. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 10 NEGATIVE: 2 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: COOK: I agree with the submitter's substantiation and do not believe that the additional labeling requirements would be an extreme burden on anyone. WELDON: The submitter emphasizes that his concerns are not initial installations but rather what follows. This is especially true today as we find more and more inexperienced people doing various electrical upgrades, additions, teledata, and telecomm installations. The code presently requires labeling intrinsically safe wiring with labels spaced not more than 25 feet that read, "intrinsic safety wiring". The submitter suggests that these labels should read, "Warning - intrinsic safe wiring - keep all wiring methods 2 inches away." He also suggests the space be reduced to 10 feet. I believe this makes good sense. I regularly see various cables, conductors, and even raceways, haphazardly thrown or pushed through ceilings, strewn as though blown with a wind, literally tied in knots and twists; intertwined like spaghetti running in all directions. Increased warning may at least raise the consciousness of inexperienced under trained people to the possibility of needed caution. ___________________

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communicated to the Panel prior to the Panel Meeting. It should be noted that all of the other Code-Making Panels accepted the metrication directive. This action will be considered by the Panel as a Public Comment. SUBMITTER: Technical Correlating Committee National Electrical Code RECOMMENDATION: In 505-3(b), change the first sentence to read: "All threaded conduit referred to herein shall be threaded with an NPT standard conduit cutting die that provides 3/4 in. a taper of 1 in 16 per foot. " In 505-15(a)(2), change "10 ft (3.05 m)" to "3.0 m (10 ft)". In 505-15(a)(2), Exception, change "12 in. (305 mm)" to "300 mm (12 in.)". In Table 505-15, reverse the order of columns for "in." and "mm" as shown below. Table 505-15. Minimum Distance of Obstruction from Flameproof "d" Flange Openings Minimum Distance Gas Group IIC IIB IIA mm 40 30 10 in. 1 37/64 1 3/16 25/64

SUBSTANTIATION: The proposed revision complies with the NFPA 1M Manual of Style Section 4-1 with respect to the placement of units, i.e., to show the SI units as the preferred unit and the inch-pound units immediately following in parenthesis. PANEL ACTION: Reject. PANEL STATEMENT: Panel 14 believes the following issues need further evaluation before changes are made to the code: trade sizes of conduit; extract policies; consistency from article to article within the code. For example, trade size of conduit is not a true dimension and cannot be converted to a true metric number. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 9 NEGATIVE: 3 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: KUCZKA: See my Explanation of Negative Vote on Proposal 1410. OMEARA: The proposal should be accepted, to be in conformance with Chapter 4 of the NFPA MOS-1 Manual of Style. ZIPSE: See my Explanation of Negative Vote on Proposal 14-10. ___________________ (Log #CP1402) 14- 318a - (505): Accept Note: The Technical Correlating Committee advises that Article Scope statements are the responsibility of the Technical Correlating Committee and the Technical Correlating Committee accepts the Panel Action. Further, it was the action of the Technical Correlating Committee that this Proposal be reconsidered by the Panel, with further consideration given to the comments expressed in the voting, specifically with respect to comments that the accepted Proposal does not accurately reflect what was agreed upon by the Panel. It is the understanding of the Technical Correlating Committee that this proposal is modified by Proposals 14-323, 14-324, 14-325, 14-326 14-327, 14-328, 14-329, 14330, 14-331, 14-334, 14-335, 14-336, 14-338, 14-339, 14-340, 14-341, 14-342, 14-344, 14-345, 14-346, 14-349, 14-350, 14-352, 14-354, 14-355, 14-356, 14-357, 14-358, 14-359, 14-360, 14-361, 14-365, 14-366, 14-368, 14-369, 14-370, 14-371, 14-372, 14-374, and 14-375. This action will be considered by the Panel as a Public Comment. SUBMITTER: CMP 14 RECOMMENDATION: Revise Article 505 to read as shown: ARTICLE 505 -- Class I, Zone 0, 1, and 2 Locations 505-1. Scope This article covers the requirements for the zone classification system as an alternative to the division classification system covered in Article 500 for electrical and electronic equipment and wiring

ARTICLE 505 -- CLASS I, ZONE 0, 1, AND 2 LOCATIONS

(Log #1263) 14- 319 - (505): Reject Note: It was the action of the Technical Correlating Committee that this Proposal be reconsidered by the Panel. The issues of raceway trade size, extracts, and use of soft versus hard metrication were all studied in detail and resolutions were

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for all voltages in Class I, Zone 0, Zone 1, and Zone 2 hazardous (classified) locations where fire or explosion hazards may exist due to flammable gases, vapors, or liquids. FPN: For the requirements for electrical and electronic equipment and wiring for all voltages in Class I, Division 1 or Division 2; Class II, Division 1 or Division 2; and Class III, Division 1 or Division 2 hazardous (classified) locations where fire or explosion hazards may exist due to flammable gases or vapors, flammable liquids, or combustible dusts or fibers, refer to Articles 500 through 504. 505-2 Definitions. For purposes of this article, the following definitions apply. Identified (as applied to equipment). Recognizable as suitable for the specific purpose, function, use, environment, application, etc., where prescribed in a particular Code requirement. FPN: Suitability of equipment for a specific purpose, environment, or application may be determined by: 3. equipment listing or labeling; 2. evidence of equipment evaluation from a qualified testing laboratory or inspection agency concerned with product evaluation; or 3. other evidence acceptable to the authority having jurisdiction such as a manufacturer's self evaluation or an owner's engineering judgment. (See definitions of Labeled and Listed ) Unclassified Locations . Locations that have been evaluated by the classification process defined in Section 500-3 5(a) or Section 505-3 5 (a) and determined to be neither Class I, Division 1; Class I, Division 2; Class I, Zone 0; Class I, Zone 1; Class I, Zone 2; Class II, Division 1; Class II, Division 2; Class III, Division 1; Class III, Division 2; or any combination thereof. Nonhazardous Locations . Locations which are not required to have been evaluated by the process defined in 500-3 5 (a) or 505-3 5 (a). Electrical and Electronic Equipment. Materials, fittings, devices, appliances, and the like that are part of, or in connection with an electrical installation, as well as any portable or transportable device having a battery or other electrical power source. (14-6) Flameproof. Type of protection where the enclosure will withstand an internal explosion of a flammable mixture that has penetrated into the interior, without suffering damage and without causing ignition, through any joints or structural openings in the enclosure, of an external explosive gas atmosphere consisting of one or more of the gases or vapors for which it is designed. FPN: See Electrical Apparatus for Use In Class I, Zone 1 and 2 Hazardous (Classified) Locations, Type of Protection -- Flameproof "d," ISA S12.22.01-1996; Electrical Apparatus for Explosive Gas Atmospheres, Part 1 -- Construction and Verification Test of Flameproof Enclosures of Electrical Apparatus, IEC 79-1-1990 and Amendment No. 1 (1993). Purged and Pressurized. Type of protection for electrical equipment that uses the technique of guarding against the ingress of the external atmosphere, which may be explosive, into an enclosure by maintaining a protective gas therein at a pressure above that of the external atmosphere. FPN No. 1: See Standard for Purged and Pressurized Enclosures for Electrical Equipment, NFPA 496-1998. FPN No. 2: See Electrical Apparatus for Explosive Gas Atmospheres - Part 2: Electrical Apparatus, Type of Protection "p," IEC 79-2-1983; and Electrical Apparatus for Explosive Gas Atmospheres - Part 13: Construction and Use of Rooms or Buildings Protected by Pressurization, IEC 79-13-1982. Intrinsic Safety. Type of protection where any spark or thermal effect is incapable of causing ignition of a mixture of flammable or combustible material in air under prescribed test conditions. FPN No. 1: See Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I, II, and

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III, Hazardous Locations, ANSI/UL 913-1997; Electrical Apparatus for Explosive Gas Atmospheres -- Part 11: Intrinsic Safety "i," IEC 60079-11-1999. FPN No. 2: Intrinsic safety is designated type of protection "ia" by IEC 79-11 for use in Zone 0 locations. Intrinsic safety is designated type of protection "ib" by IEC 79-11 for use in Zone 1 locations. FPN No. 3: Intrinsically safe associated apparatus, designated by [ia] or [ib], is connected to intrinsically safe equipment ("ia" or "ib" respectively), but is located outside the hazardous (classified) location unless also protected by another type of protection (such as flameproof). Type of Protection "n." Type of protection where electrical equipment, in normal operation, is not capable of igniting a surrounding explosive gas atmosphere and a fault capable of causing ignition is not likely to occur. FPN: see Electrical Apparatus for Explosive Gas Atmospheres, Part 15 -- Electrical Apparatus with Type of Protection "n," IEC 79-15-1987. Oil Immersion "o." Type of protection where electrical equipment immersed in a protective liquid in such a way that an explosive atmosphere that may be above the liquid or outside the enclosure cannot be ignited. FPN: See Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations, Type of Protection -- Oil-Immersion "o," ISA S12.26.01 -- 1996; and Electrical Apparatus for Explosive Gas Atmospheres, Part 6 -- Oil-Immersion "o," IEC 79-6-1995. Increased Safety "e." Type of protection where electrical equipment that does not produce arcs or sparks in normal service and under specified abnormal conditions, in which additional measures are applied so as to give increased security against the possibility of excessive temperatures and of the occurrence of arcs and sparks. FPN: See Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations, Type of Protection -- Increased Safety "e," ISA S12.16.01-1996; and Electrical Apparatus for Explosive Gas Atmospheres -- Part 7: Increased Safety "e," IEC 79-7-1990, Amendment No. 1 (1991), and Amendment No. 2 (1993). Encapsulation "m." Type of protection where electrical parts that could ignite an explosive atmosphere by either sparking or heating are enclosed in a compound in such a way that this explosive atmosphere cannot be ignited. FPN: See Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations Type of Protection -- Encapsulation "m," ISA S12.23.01-1996, and Electrical Apparatus for Explosive Gas Atmospheres -- Part 18: Encapsulation "m," IEC 79-18-1992. Powder Filling "q." Type of protection where electrical parts capable of igniting an explosive atmosphere are fixed in position and completely surrounded by filling material (glass or quartz powder) to prevent the ignition of an external explosive atmosphere. FPN: See Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations Type of Protection -- Powder Filling "q," ISA S12.25.01-1996, and Electrical Apparatus for Explosive Gas Atmospheres -- Part 5: Powder Filling, Type of Protection "q," IEC 79-5-1967.

505-32. Other Articles All other applicable rules contained in this Code shall apply to electrical equipment and wiring installed in hazardous (classified) locations. Exception: As modified by Article 504 and this article. 505-3 4 General (a) Documentation for Industrial Occupancies. All areas in industrial occupancies designated as hazardous (classified) locations shall be properly documented. This documentation shall be available to those authorized to design,

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install, inspect, maintain, or operate electrical equipment at the location. FPN: For examples of area classification drawings, see Electrical Apparatus for Explosive Gas Atmospheres, Classification of Hazardous Areas, IEC 79-10-1995; Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Zone 0, Zone 1, or Zone 2, API RP 505-1997; Electrical Apparatus for Explosive Gas Atmospheres, Classifications of Hazardous (Classified) Locations, ISA S12.24.01-1997; Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Division I or Division 2, API RP 5001997, Model Code of Safe Practice in the Petroleum Industry, Part 15: Area Classification Code for Petroleum Installations, IP 15, The Institute of Petroleum, London. (b) Reference Standards. FPN No. 1: It is important that the authority having jurisdiction be familiar with recorded industrial experience as well as with standards of the National Fire Protection Association, the American Petroleum Institute, and the International Society for Measurement and Control (ISA), that may be of use in the classification of various locations, the determination of adequate ventilation, and the protection against static electricity and lightning hazards. FPN No. 2: For further information on the classification of locations, see Electrical Apparatus for Explosive Gas Atmospheres, Classification of Hazardous Areas, IEC 7910-1995; Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Zone 0, Zone 1, or Zone 2, ANSI/ API RP 505-19976; Electrical Apparatus for Explosive Gas Atmospheres, Classifications of Hazardous (Classified) Locations, ISA S12.24.01-1997; and Model Code of Safe Practice in the Petroleum Industry, Part 15: Area Classification Code for Petroleum Installations, IP 15, The Institute of Petroleum, London. FPN No. 3: For further information on protection against static electricity and lightning hazards in hazardous (classified) locations, see Recommended Practice on Static Electricity, NFPA 77-1993; Standard for the Installation of Lightning Protection Systems, NFPA 7801997; and Protection Against Ignitions Arising Out of Static Lightning and Stray Currents, API RP 2003-1991. FPN No. 4: For further information on ventilation, see Flammable and Combustible Liquids Code, NFPA 301996, and Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Division 1 or Division 2, API RP 500-1997, Section 6.3. FPN No. 5: For further information on electrical systems for hazardous (classified) locations on offshore oil and gas producing platforms, see Recommended Practice for Design and Installation of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassifed and Class I, Zone 0, Zone 1, and Zone 2 LocationsProduction Platforms, ANSI/API RP 14FZ20001991. FPN No. 6: For further information on the installation of electrical equipment in hazardous (classified) locations in general, see Electrical Apparatus for Explosive Gas Atmospheres -- Part 14: Electrical Installations in Explosive Gas Atmospheres (Other than Mines), IEC 7914-1996, and Electrical Apparatus for Explosive Gas Atmospheres -- Part 16: Artificial Ventilation for the Protection of Analyzer(s) Houses, IEC 79-16-1990. 505-4 5 Classifications of Locations (a) Classification of Locations. Locations shall be classified depending on the properties of the flammable vapors, liquids, or gases that may be present and the likelihood that a flammable or combustible concentration or quantity is present. Where pyrophoric materials are the only materials used or handled, these locations shall not be classified. Each room, section, or area shall be considered individually in determining its classification.

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FPN No. 1: See Section 505-6 7 for restrictions on area classification. FPN No. 2: Through the exercise of ingenuity in the layout of electrical installations for hazardous (classified) locations, it is frequently possible to locate much of the equipment in reduced level of classification or in an unclassified location less hazardous or in nonhazardous locations and, thus, to reduce the amount of special equipment required.

Rooms and areas containing ammonia r efrigeration systems that are equipped with adequate mechanical ventilation, may be classified as "unclassified" locations. FPN: For further information regrading classification and ventilaton of areas involving ammonia, see Safety Code for Mechanical Refrigeration, ANSI/ASHRAE 15-1994, and Safety Requirements for the Storage and Handling of Anhydrous Ammonia, ANSI/CGA G2.1-1989 (14-39) (b) Class I Zone Locations. Class I Zone locations are those in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitible mixtures. Class I Zone locations shall include those specified in (1), (2) and (3). (1) Class I, Zone 0. A Class I, Zone 0 location is a location (a) In which ignitible concentrations of flammable gases or vapors are present continuously, or (b) In which ignitible concentrations of flammable gases or vapors are present for long periods of time. FPN No. 1: As a guide in determining when flammable gases or vapors are present continuously or for long periods of time, refer to Recommended Practice for Classification of Locations for Electrical Installations of Petroleum Facilities Classified as Class I, Zone 0, Zone 1 or Zone 2, API RP 505-1996; Electrical Apparatus for Explosive Gas Atmospheres, Classifications of Hazardous Areas, IEC 79-10-1995; and Area Classification Code for Petroleum Installations, Model Code, Part 15, Institute of Petroleum; and Electrical Apparatus for Explosive Gas Atmospheres, Classifications of Hazardous (Classified) Locations, ISA S12.24.01-1997. FPN No. 2: This classification includes locations inside vented tanks or vessels that contain volatile flammable liquids; inside inadequately vented spraying or coating enclosures, where volatile flammable solvents are used; between the inner and outer roof sections of a floating roof tank containing volatile flammable liquids; inside open vessels, tanks and pits containing volatile flammable liquids; the interior of an exhaust duct that is used to vent ignitible concentrations of gases or vapors; and inside inadequately ventilated enclosures that contain normally venting instruments utilizing or analyzing flammable fluids and venting to the inside of the enclosures. FPN No. 3: It is not good practice to install electrical equipment in Zone 0 locations except when the equipment is essential to the process or when other locations are not feasible. [See Section 505-3(a) FPN No. 2.] If it is necessary to install electrical systems in a Zone 0 location, it is good practice to install intrinsically safe systems as described by Article 504. (2) Class I, Zone 1. A Class I, Zone 1 location is a location (a) In which ignitible concentrations of flammable gases or vapors are likely to exist under normal operating conditions; or (b) In which ignitible concentrations of flammable gases or vapors may exist frequently because of repair or maintenance operations or because of leakage; or (c) In which equipment is operated or processes are carried on, of such a nature that equipment breakdown or faulty operations could result in the release of ignitible concentrations of flammable gases or vapors and also cause simultaneous failure of electrical equipment in a mode to cause the electrical equipment to become a source of ignition; or (d) That is adjacent to a Class I, Zone 0 location from which ignitible concentrations of vapors could be communicated, unless communication is prevented by adequate positive pressure ventilation from a source of clean air and effective safeguards against ventilation failure are provided. FPN No. 1: Normal operations is considered the situation when plant equipment is operating within its

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design parameters. Minor releases of flammable material may be part of normal operations. Minor releases include the releases from mechanical packings on pumps. Failures that involve repair or shutdown (such as the breakdown of pump seats and flange gaskets, and spillage caused by accidents) are not considered normal operation. FPN No. 2: This classification usually includes locations where volatile flammable liquids or liquefied flammable gases are transferred from one container to another. In areas in the vicinity of spraying and painting operations where flammable solvents are used; adequately ventilated drying rooms or compartments for evaporation of flammable solvents; adequately ventilated locations containing fat and oil extraction equipment using volatile flammable solvents; portions of cleaning and dyeing plants where volatile flammable liquids are used; adequately ventilated gas generator rooms and other portions of gas manufacturing plants where flammable gas may escape; inadequately ventilated pump rooms for flammable gas or for volatile flammable liquids; the interiors of refrigerators and freezers in which volatile flammable materials are stored in the open, lightly stoppered, or easily ruptured containers; and other locations where ignitible concentrations of flammable vapors or gases are likely to occur in the course of normal operation, but not classified Zone 0. (3) Class I, Zone 2. A Class I, Zone 2 location is a location (a) In which ignitible concentrations of flammable gases or vapors are not likely to occur in normal operation and if they do occur will exist only for a short period; or (b) In which volatile flammable liquids, flammable gases, or flammable vapors are handled, processed, or used, but in which the liquids, gases, or vapors normally are confined within closed containers of closed systems from which they can escape, only as a result of accidental rupture or breakdown of the containers or system, or as a result of the abnormal operation of the equipment with which the liquids or gases are handled, processed, or used; or (c) In which ignitible concentrations of flammable gases or vapors normally are prevented by positive mechanical ventilation, but which may become hazardous as a result of failure or abnormal operation of the ventilation equipment; or (d) That is adjacent to a Class I, Zone 1 location, from which ignitible concentrations of flammable gases or vapors could be communicated, unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air, and effective safeguards against ventilation failure are provided. FPN: The Zone 2 classification usually includes locations where volatile flammable liquids or flammable gases or vapors are used, but which would become hazardous only in case of an accident or of some unusual operating condition. 505-5 6 Material Groups For purposes of testing, approval, and area classification, various air mixtures (not oxygen enriched) shall be grouped as required in (a), (b), and (c). FPN: Group I is intended for use in describing atmospheres that contain firedamp (a mixture of gases, composed mostly of methane, found underground, usually in mines). This Code does not apply to installations underground in mines. See Section 90-2(b). Group II shall be subdivided into IIC, IIB, and IIA, as noted in (a), (b), and (c), according to the nature of the gas or vapor, for protection techniques "d," "ia," "ib," "[ia]," and "[ib]," and, where applicable, "n" and "o." FPN No. 1: The gas and vapor subdivision as described above is based on the maximum experimental safe gap (MESG), minimum igniting current (MIC), or both. Test equipment for determining the MESG is described in Construction and Verification Tests of Flameproof Enclosures of Electrical Apparatus, IEC 79-1A-1975, Amendment No. 1 (1993) and UL Technical Report No. 58 (1993). The test equipment for determining MIC is described in Spark-Test Apparatus for Intrinsically-Safe Circuits, IEC 79-3-1990. The classification of gases or vapors according to their maximum experimental safe gaps and minimum igniting currents is described in Classification of Mixtures of Gases or Vapours with Air According to Their Maximum Experimental Safe Gaps and Minimum Igniting Currents, IEC 79-12-1978.

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FPN No. 2: Verification of electrical equipment utilizing protection techniques "e," "m," "p," and "q," due to design technique, does not require tests involving MESG or MIC. Therefore, Group II is not required to be subdivided for these protection techniques. FPN No. 3: It is necessary that the meanings of the different equipment markings and Group II classifications be carefully observed to avoid confusion with Class I, Divisions 1 and 2, Groups A, B, C, and D.

(a) Class I Zone Group Classifications. Class I Zone groups shall be as follows: (1) Group IIC. Atmospheres containing acetylene, hydrogen, or flammable gas, flammable liquid-produced vapor, or combustible liquid-produced vapor mixed with air that may burn or explode, having either a maximum experimental safe gap (MESG) value less than or equal to 0.50 mm or minimum igniting current ratio (MIC ratio) less than or equal to 0.45. FPN: Group IIC is equivalent to a combination of Class I, Group A, and Class I, Group B, as described in Sections 500-5(a)(1) and (a)(2). (2) Group IIB. Atmospheres containing acetaldehyde, ethylene, or flammable gas, flammable liquid-produced vapor, or combustible liquid-produced vapor mixed with air that may burn or explode, having either maximum experimental safe gap (MESG) values greater than 0.50 mm and less than or equal to 0.90 mm or minimum igniting current ratio (MIC ratio) greater than 0.45 and less than or equal to 0.80. FPN: Group IIB is equivalent to Class I, Group C, as described in Section 500-5(a)(3). (3) Group IIA. Atmospheres containing acetone, ammonia, ethyl alcohol, gasoline, methane, propane, or flammable gas, flammable liquid-produced vapor, or combustible liquid-produced vapor mixed with air that may burn or explode, having either a maximum experiment safe gap (MESG) value greater than 0.90 mm or minimum igniting current ratio (MIC ratio) greater than 0.80. FPN: Group IIA is equivalent to Class I, Group D as described in Section 500-5(a)(4). 505-6 7 Special Precaution Article 505 requires equipment construction and installation that will ensure safe performance under conditions of proper use and maintenance. FPN No. 1: It is important that inspection authorities and users exercise more than ordinary care with regard to the installation and maintenance of electrical equipment in hazardous (classified) locations. FPN No. 2: Low ambient conditions require special consideration. Electrical equipment depending on the protection techniques described by Section 505-4(a) may not be suitable for use at temperatures lower than -20ºC (-13ºF) unless they are approved for use at lower temperatures. However, at low ambient temperatures, flammable concentrations of vapors may not exist in a location classified Class I, Zones 0, 1, or 2 at normal ambient temperature. (a) Supervision of Work. Classification of areas and selection of equipment and wiring methods shall be under the supervision of a qualified Registered Professional Engineer. (14-348) (ab) Dual Classification. In instances of areas within the same facility classified separately, Class I, Zone 2 locations shall be permitted to abut, but not overlap, Class I, Division 2 locations. Class I, Zone 0 or Zone 1 locations shall not abut Class I, Division 1 or Division 2 locations. (b c) Reclassification Permitted. A Class I, Division 1 or Division 2 location shall be permitted to be reclassified as a Class I, Zone 0, Zone 1, or Zone 2 location provided all of the space that is classified because of a single flammable gas or vapor source is reclassified under the requirements of this article. 505- 7 8 Protection Techniques

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The following shall be acceptable protection techniques for electrical and electronic equipment in hazardous (classified) locations. FPN: For additional information, see Electrical Apparatus for Use in Class I, Zone 0, 1 Hazardous (Classified) Locations General Requirements, ISA S12.0.01-1997; Electrical Equipment for Use in Class I, Zone 0, 1, and 2 Hazardous (Classified) Locations, ANSI/UL 2279, 1997; and Electrical Apparatus for Explosive Gas Atmospheres - Part 0: General Requirements, IEC 79-0-1983, Amendment No. 1 (1987), and Amendment No. 2 (1991). (a) Flameproof "d." This protection technique shall be permitted for equipment in Class I, Zone 1 or Zone 2 locations. (b) Purged and Pressurized. This protection technique shall be permitted for equipment in those Class I, Zone 1 or Zone 2 locations for which it is approved. (c) Intrinsic Safety. This protection technique shall be permitted for equipment in Class I, Zone 0 or Zone 1 locations for which it is approved. (d) Type of Protection "n." This protection technique shall be permitted for equipment in Class I, Zone 2 locations. Type of protection "n" is further subdivided into nA, nC, and nR. FPN: See Table 505-10(b) 1 for the descriptions of subdivisions for type of protection "n." (e) Oil Immersion "o." This protection technique shall be permitted for equipment in Class I, Zone 1 locations. (f) Increased Safety "e." This protection technique shall be permitted for equipment in Class I, Zone 1 locations. (g) Encapsulation "m." This protection technique shall be permitted for equipment in Class I, Zone 1 locations. (h) Powder Filling "q." This protection technique shall be permitted for equipment in Class I, Zone 1 locations. 505-8 9 Equipment (a) Listing. (1) Equipment that is listed for a Zone 0 location shall be permitted in a Zone 1 or Zone 2 location of the same gas or vapor. Equipment that is identified listed for a Zone 1 location shall be permitted in a Zone 2 location of the same gas or vapor. (2) Equipment shall be permitted to be listed for a specific gas or vapor, specific mixtures of gases or vapors, or any specific combination of gases or vapors. FPN: One common example is equipment marked for "IIB + H2." (b) Marking Equipment shall be marked in accordance with (1) or (2). (1) Division Equipment. Equipment identified approved for Class I, Division 1 or Class I, Division 2 shall, in addition to being marked in accordance with Section 500-56(d), be permitted to be marked with the following: a. Class I, Zone 1 or Class I, Zone 2 (as applicable), and b. Applicable gas classification group(s) in accordance with Table 505-89(b)(2), and c. Temperature classification in accordance with Section 505-8 9(3) (2) Zone Equipment. Equipment meeting one or more of the protection techniques described in Section 505-4 5 shall be marked with the following in the order shown: a. Class b. Zone c. Symbol "AEx" d. Protection technique(s) in accordance with Table 505-89(b)(2) e. Applicable gas classification group(s) in accordance with Table 505-89(b)(2) f. Temperature classification in accordance with Section 505-89(c) Exception: Intrinsically safe associated apparatus shall be required to be marked only with (c), (d), and (e). *

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FPN No. 1: An example of such a required marking is "Class I, Zone 0, AEx ia IIC T6." Electrical equipment of types of protection "e," "m," "p," or "q," shall be marked Group II. Electrical equipment of types of protection "d," "ia," "ib," "[ia]," or "[ib]" shall be marked Group IIA, or IIB, or IIC, or for a specific gas or vapor. Electrical equipment of types of protection "n" shall be marked Group II unless it contains enclosedbreak devices, nonincendive components, or energylimited equipment or circuits, in which case it shall be marked Group IIA, IIB, or IIC, or a specific gas or vapor. Electrical equipment of other types of protection shall be marked Group II unless the type of protection utilized by the equipment requires that it shall be marked Group IIA, IIB, or IIC, or a specific gas or vapor. FPN No. 2: An explanation of the marking that is required follows.

Figure 505-8 9(b)(1).

Table 505-8 9(b)(1). Types of Protection Designation

Designatio n d e ia ib [ia] Technique Flameproof enclosure Increased safety Intrinsic safety Intrinsic safety Intrinsically safe associated apparatus Intrinsically safe associated apparatus Encapsulation Nonsparking equipment Sparking equipment in which the contacts are suitably protected other than by restricted breathing enclosure Restricted breathing enclosure Oil immersion Purged and pressurized Powder filled Zone* 1 1 0 1 Unclassified or Nonhazardous Unclassified or Nonhazardous 1 2 2

[ib]

m nA nC

nR o p q

2 1 1 or 2 1

Does not address use where a combination of techniques is used.

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Table 505-8 9(b)(2). Gas Classification Groups Gas Group IIC IIB IIA (c) Class I Temperature The temperature marking shall not exceed the ignition temperature of the specific gas or vapor to be encountered. FPN: For information regarding ignition temperatures of gases and vapors, see Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 497-1997; Guide to Fire Hazard Properties of Flammable Liquids, Gases, and Volatile Solids, NFPA 325-1994; and Electrical Apparatus for Explosive Gas Atmospheres, Data for Flammable Gases and Vapours, Relating to the Use of Electrical Apparatus, IEC 79-20-1996. (1) Temperature Classifications. Approved equipment shall be marked to show the operating temperature or temperature range class referenced to a 40ºC (104ºF) ambient. The temperature rangeclass , if provided, shall be indicated using the temperature class (T Code) in identification numbers, as shown in Table 505-8 9 (c). Table 505-8 9(c). Classification of Maximum Surface Temperature for Group II Electrical Equipment Temperature Class (T Code) T1 T2 T3 T4 T5 T6 Maximum Surface Temperature (ºC) 450 300 200 135 100 85 Comment See Section 505-6(a) See Section 505-6(b) See Section 505-6(c)

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(1) Equipment Provided with Threaded Entries for NPT Threaded Conduit or Fittings. For equipment provided with threaded entries for NPT threaded conduit or fittings, listed conduit, conduit fittings, or cable fittings shall be used. FPN: Threading specifications for NPT threads are located in Pipe Threads, General Purpose (Inch), ANSI /ASME B1.20.1-1983. (2) Equipment Provided with Threaded Entries for Metric Threaded Conduit or Fittings. For equipment with metric threaded entries, such entries shall be identified as being metric, or listed adapters to permit connection to conduit or NPT-threaded fittings shall be provided with the equipment. Adapters shall be used for connection to conduit or NPT-threaded fittings. Listed cable fittings that have metric threads shall be permitted to be used. FPN: Threading specifications for metric threaded entries are located in Metric Screw Threads, ISO 965/1:1980, and Metric Screw Threads, ISO 965/3:1980. 505-15. Wiring Methods (a) Zone 0. In Class I, Zone 0 locations, only the following wiring methods shall be permitted. 1. Intrinsically safe wiring in accordance with Article 504. FPN: Article 504 only includes protection technique "ia." 2. Seals shall be provided within 10 ft (3.05 m) of where a conduit leaves a Zone 0 location. There shall be no unions, couplings, boxes, or fittings, except reducers at the seal, in the conduit run between the seal and the point at which the conduit leaves the location. Exception: A rigid unbroken conduit that passes completely through the Zone 0 location with no fittings less than 12 in. (305 mm) beyond each boundary, shall not be required to be sealed, if the termination points of the unbroken conduit are in unclassified locations. 3. Seals shall be provided on cables at the first point of termination after entry into the Zone 0 location. 4. Seals shall not be required to be explosionproof or flameproof. (b) Zone 1. In Class I, Zone 1 locations, all wiring methods permitted for Class I, Division 1 locations shall be permitted.

Electrical equipment designed for use in the ambient temperature range between -20ºC and +40ºC shall require no additional Where Class I, Division 1 wiring methods are used, sealing and temperature marking. drainage shall be provided in accordance with Sections 501-5(a), Electrical equipment that is designed for use in a range of ambient (c), (d), and (f), except where the term "Division 1" is used "Zone temperatures other than -20ºC and +40ºC is considered to be 1" shall be substituted. special; and the ambient temperature range shall then be marked on the equipment, including either the symbol "Ta" or "Tamb" An explosionproof seal, constructed in accordance with Section together with the special range of ambient temperatures. As an 501-5(c), shall be provided for each conduit entering an enclosure example, such a marking might be "-30ºC Ta + 40ºC." having type of protection "e" or "d," except where the type of Electrical equipment suitable for ambient temperatures exceeding protection "d" enclosure is marked to indicate that a seal is not 40ºC (104ºF) shall be marked with both the maximum ambient required. temperature and the operating temperature or temperature range class at that ambient temperature. Wiring methods shall maintain the integrity of protection techniques. Exception No. 1: Equipment of the nonheat-producing type, such as FPN No. 1: For example, equipment with type of conduit fittings, and equipment of the heat-producing type having a protection "e" requires that conduit seals or cable fittings maximum temperature of not more than 100ºC (212ºF) shall not be incorporate suitable methods to maintain the "ingress required to have a marked operating temperature or temperature protection" (minimum IP54) of the enclosure; and, for range class. conduit, serve to maintain the explosionproof integrity of Exception No. 2: Equipment approved for Class I, Division 1 or Division the conduit system. 2 locations as permitted by Sections 505-20(b) and (c) shall be permitted to be marked in accordance with Section 500-5and Table 500-5 6(d) 6(d). FPN No. 2: Different electrical enclosures provide different degrees of "ingress protection." The measures (d) Threading applied to enclosures of electrical apparatus include All threaded conduit referred to herein shall be threaded with an 1. The protection of persons against contact with or Nati onal (American) Standard Pipe Taper ( NPT ) standard approach to live parts and against contact with moving conduit cutting die that provides _-in. taper per foot. Such conduit parts (other than smooth rotating shafts and the like) shall be made wrenchtight to prevent sparking when fault current inside the enclosure; flows through the conduit system, and to ensure the 2. The protection of the apparatus inside the enclosure explosionproof or flameproof integrity of the conduit system where against ingress of solid foreign bodies; and applicable. Threaded joints shall be made up with at least five 3. The protection of the apparatus inside the enclosure threads fully engaged. against harmful ingress of water. Equipment provided with threaded entries for field wiring (c) Zone 2. In Class I, Zone 2 locations, all wiring methods connections shall be installed in accordance with (1) or (2). permitted for Class I, Division 2 locations shall be permitted. Sealing and drainage shall be provided in accordance with Sections 501-5(b), (c), (e), and (f), except where the term "Division 2" is

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used, "Zone 2" shall be substituted and where the term "Division 1" is used, "Zone 1" shall be substituted. Wiring methods shall maintain the integrity of protection techniques. (d) Solid Obstacles. Flameproof equipment with flanged joints shall not be installed such that the flange openings are closer than the distances shown in Table 505-15 to any solid obstacle that is not a part of the equipment (such as steelworks, walls, weather guards, mounting brackets, pipes, or other electrical equipment) unless the equipment is listed for a smaller distance of separation. Table 505-15. Minimum Distance of Obstructions from Flameproof "d" Flange Openings Minimum Distance In. 1 37/64 1 3/16 25/64 Minimum Distance Mm 40 30 10

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(1) Conduit seals shall be provided for each conduit entering enclosures having type of protection `d' or `e'. Exception: Where the enclosure having type of protection `d' is marked to indicate that a seal is not required. Conduit seals shall be provided for each conduit entering explosionproof equipment as follows. (a ) In each conduit entry int o an explosionproof enclosure where either (1) the enclosure contains apparatus, such as switches, circuit breakers, fuses, relays, or resistors, that may produce arcs, sparks, or high temperatures that are considered to be an ignition source in normal operation, or (2) the entry is 2-in. size or larger and the enclosure contains terminals, splices, or taps. For the purposes of this section high temperatures shall be considered to be any temperatures exceeding 80 percent of the autoignition temperature in d egrees Celsius of the gas or vapor involved. Exception: Conduit entering an enclosure where such switches, circuit breakers, fuses, relays, or resistors are 1. Enclosed within a chamber hermetically sealed against the entrance of gases or vapors, or 2. Imm ersed in oil, or 3. Enclosed within a factory-sealed explosionproof chamber located within the enclosure, approved for the location, and marked "factory sealed" or equivalent. Factory-sealed enclosures shall not be considered to serve as a seal for another adjacent explosionproof enclosure that is required to have a conduit seal. (b) Conduit seals shall be installed within 18 in. (457 mm) from the enclosure. Only explosionproof unions, couplings, reducers, elbows, capped elbows, and conduit bodies similar to L, T, and Cross types that are not larger than the trade size of the conduit shall be permitted between the sealing fitting and the explosionproof enclosure. (c ) Where two or more explosionproof enclosures for which conduit seals are required under (b )(2) are connected by nipples or by runs of conduit not more than 36 in. (914 mm) long, a single conduit seal in each such nipple connection or run of conduit shall be considered sufficient if located not more than 18 in. (457 mm) from either enclosure. ( 3) In each conduit entry into a pressurized enclosure where the conduit is not pressurized as part of the protection system. Conduit seals shall be installed within 18 in. (457 mm) from the pressurized enclosure. FPN No. 1: Installing the seal as close as possible to the enclosure will reduce problems with purging the dead airspace in the pressurized conduit. FPN No. 2: For further information, see Standard for Purged and Pressurized Enclosures for Electrical Equipment, NFPA 496-1998.

Gas Group IIC IIB IIA

505-16. Sealing and Drainage. Seals in conduit and cable systems shall comply with (a) through (e). Sealing compound shall be used in Type MI cable termination fittings to exclude moisture and other fluids from the cable insulation. FPN No. 1: Seals are provided in conduit and cable systems to minimize the passage of gases and vapors and prevent the passage of flames from one portion of the electrical installation to another through the conduit. Such communication through Type MI cable is inherently prevented by construction of the cable. Unless specifically designed and tested for the purpose, conduit and cable seals are not intended to prevent the passage of liquids, gases, or vapors at a continuous pressure differential across the seal. Even at differences in pressure across the seal equivalent to a few inches of water, there may be a slow passage of gas or vapor through a seal, and through conductors passing through the seal. See Section 505-16( c)(2)(b). Temperature extremes and highly corrosive liquids and vapors can affect the ability of seals to perform their intended function. See Section 50516(d)(2). FPN No. 2: Gas or vapor leakage and propagation of flames may occur through the interstices between the strands of standard stranded conductors larger than No. 2. Special conductor constructions, e.g., compacted strands or sealing of the individual strands, are means of reducing leakage and preventing the propagation of flames. (a) Zone 0. In Class I, Zone 0 locations, seals shall be located as follows. (1) Seals shall be provided within 10 ft (3.05 m) of where a conduit leaves a Zone 0 location. There shall be no unions, couplings, box es, or fittings, except reducers at the seal, in the conduit run between the seal and the point at which the conduit leaves the location.

(4 ) In each conduit run leaving a Class I, Zone 1 location. The sealing fitting shall be permitted on either side of the boundary of such location within 10 ft (3.05 m) of the boundary, and shall be designed and installed so to minimize the amount of gas or vapor within the Zone 1 portion of the conduit from being communicated to the conduit beyond the seal. Except for listed explosionproof reducers at the conduit seal, there shall be no Exception: A rigid unbroken conduit that passes completely through the union, coupling, box, or fitting between the conduit seal and the Zone 0 location with no fittings less thanin. (305 mm) beyond each 12 point at which the conduit leaves the Zone 1 location. boundary, shall not be required to be sealed, if the termination points of Exception: Metal conduit containing no unions, couplings, boxes, the unbroken conduit are in unclassified locations. or fittings that passes completely through a Class I, Zone 1 location with no fittings less than 12 in. (305 mm) beyond each boundary (2) Seals shall be provided on cables at the first point of shall not require a conduit seal if the termination points of the termination after entry into the Zone 0 location. unbroken conduit are in unclassified locations. (3) Seals shall not be required to be explosionproof or flameproof. (b) Zone 1. In Class I, Zone 1 locations, seals shall be located as follows. (5) Conduits containing cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall be sealed in the Zone 1 location after removing the jacket and any other coverings so that the sealing compound will surround each individual insulated conductor and the outer jacket.

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Exception: Multiconductor cables with a gas/ vaportightcontinuous sheath capable of transmittingses or vapors through the cable core shall ga be permitted to be considered as a single conductor by sealing the cable in the conduit within 18 in. (457 mm) of the enclosure and the cable end within the enclosure by an approved means to minimize the entrance of gases or vapors and prevent the propagation of flame into the cable core, or by other approved methods. shielded cables and twisted pair cables, For it shall not be required to remove the shielding material or separate the twisted pair. (6) Each multic onductor cable in conduit shall be considered as a single conductor if the cable is incapable of transmitting gases or vapors through the cable core. These cables shall be sealed in accordance with (d). (7) Cable seals shall be provided for each cable ent ering flameproof or explosionproof enclosures. The seal shall comply with (d). (8) Cables shall be sealed at the point at which they leave the Zone 1 location. Exception: Where cable is sealed at the termination point. (c ) Zone 2. In Class I, Zone 2 locations, seals shall be located as follows. (1) Conduit seals shall be located as follows. (a ) For connections to enclosures that are required to be flameproof or explosionproof, a conduit seal shall be provided in accordance with (b)(1) and (b)(2). All portions of the conduit run or nipple between the seal and such enclosure shall comply with Section 505-16(b). 2. In each conduit run passing from a Class I, Zone 2 location into an unclassified location. The sealing fitting shall be permitted on either side of the boundary of such location within 10 ft (3.05 m) of the boundary, and shall be designed and installed so to minimize the amount of gas or vapor within the Zone 2 portion of the conduit from being communicated to the conduit beyond the seal. Rigid metal conduit or threaded steel intermediate metal conduit shall be used between the sealing fitting and the point at which the conduit leaves the Zone 2 location, and a threaded connection shall be used at the sealing fitting. Except for liste d explosionproof reducers at the conduit seal, there shall be no union, coupling, box, or fitting between the conduit seal and the point at which the conduit leaves the Zone 2 location. Exception No. 1: Metal conduit containing no unions, couplings, boxes or fittings that passes completely through a Class I 2 location with , Zone no fittings less than 12 in. (305 mm) beyond each boundary shall not be required to be sealed if the termination points of the unbroken conduit in unclassified locations.

Copyright 2000, NFPA

1. No part of the conduit system segment passes through a Class I, Zone 0 or Class I, Zone 1 location where the conduit contains unions, couplings, boxes, or fittings within 12 in. (305 mm) of the Class IZone0 or ClassI, Zone 1 location; , and 2. The conduit system segment is located entirely in outdoor locations; and 3. The conduit system segment is not directly connected to canned pumps, process or service connections for flow, pressure, or analysis measurement,, etc. depend on a that single compression seal, diaphragm, or tube to prevent flammable or combustible fluids from entering the conduit system; and 4. The conduit system segment contains only threaded metal conduit, unions, couplings, conduit bodies, and fittin the ings unclassified location; and 5. The conduit system segment is sealed at its entry to each enclosure or fitting housing terminals, splices, or taps in Class I, Zone2 locations.

(2) Cable seals shall be located as follows. (a) Cables entering enclosures required to be flameproof or explosionproof shall be sealed at the point of entrance. The seal shall comply with (d). Multiconductor cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core s hall be sealed in the Zone 2 location after removing the jacket and any other coverings so that the sealing compound will surround each individual insulated conductor in such a manner as to minimize the passage of gases and vapors. Multiconductor cables in conduit shall be sealed as described in (b)(4). Exception No. 1: Cables passing from an enclosure or room that is unclassified as a result of Type Z pressurization into a Class I, Zone 2 location shall not require a seal at the boundary. Exception No.: 2 Shielded cables and twisted pair cables shall not require the removal of the shielding material or separation of the twisted pairs provided the termination is by an approved means to minimize the entrance of gases or vapors and prevent propagation of into the me fla cable core.

(b) Cables with a gas/vaportight continuous sheath and that will not transmit gases or vapors through the cable core in excess of the quantity permitted for seal fittings shall not be required to be are sealed except as required in (2)(a). The minimum length of such cable run shall not be less than that length that limits gas or vapor flow through the cable core to the rate permitted for seal fittings Exception No. 2: Conduit systems terminating at an unclassified location [0.007 ft3/hour (198 cm3/hour) of air at a pressure of 6 in. of where a wiring method transition is made to cable tray, cablebus, water (1493 pascals)]. ventilated busway, Type MI cable, or open wiring shall not be required to be sealed where passing from the Class I e 2 location into the , Zon FPN No. 1: See Outlet Boxes and Fittings for Use in unclassified location. The unclassified location shall be outdoors or, if the Hazardous (Classified) Locations, ANSI/UL 886-1994. conduit system is all in one room, it shall be permitted to be indoors. The conduits shall not terminate at an enclosure containing an ignition FPN No. 2: The cable core does not include the source in no rmal operation. interstices of the conductor strands. Exception No. 3: Conduit systems passing from an enclosure or room that Cables with a gas/ vaportight continuous sheath capable of (c) is unclassified as a result of pressurization into a Class I, Zone 2 transmitting gases or vapors through the cable core shall not be location shall not require a seal at the boundary. required to be sealed except as required in (2)(a), unless the cable is attached to process equipment or devices that may cause a FPN: For further information, refer to Standa rd for pressure in excess of 6 in. of water (1493 pascals) to be exer ted at a Purged and Pressurized Enclosures for Electrical cable end, in which case a seal, barrier, or other means shall be Equipment, NFPA 496-1998. provided to prevent migration of flammables into an unclassified area. Exception No. 4: Segments of aboveground conduit systems shall not be required to be sealed where passing from a Class I 2 location into , Zone an unclassified location if t following conditions are met: he

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Copyright 2000, NFPA

Exception: Cables with an unbroken gas/vaportight continuous sheath shall be permitted to pass through a sClasZone2 location without I, Drains, vents, or other devices shall be provided so that seals. primary seal leakage will be obvious. (d) Cables that do not have gas/vaportight continuous sheath shall be sealed at the boundary of the Zone 2 and unclassified location in such a manner as to minimize the passage of gases or vapors into an unclassified location. FPN: The cable sheath may be either metal or a nonmetallic material. (d) Class I, Zones 0, 1 and 2. Where required, seals in Class I, Zones 0 , 1 and 2 locations shall comply with the following. (1) Fittings. Enclosures for connections or equi pment shall be provided with an integral means for sealing, or sealing fittings for Class I locations shall be used. Sealing fittings shall be accessible. Sealing fittings shall be listed for use with one or more specific compounds and shall be accessible. (2) Compound. The compound shall provide a seal against passage of gas or vapors through the seal fitting, shall not be affected by the surrounding atmosphere or liquids, and shall not have a melting point of less than 93ºC (200ºF). (3) Thickness of Compounds. In a completed seal, the minimum thickness of the sealing compound shall not be less than the trade size of the sealing fitting and, in no case, less than 5/8 in. (16 mm). Exception: Listed cable sealing fittings shall not be required to have a minimum thickness equal to the trade size of the fitting. (4) Splices and Taps. Splices and taps shall not be made in fittings intended only for sealing with compound, nor shall other fittings in which splices or taps are made be filled with compound. (5) Conductor Fill. The cross-sectional area of the conductors permitted in a seal shall not exceed 25 percent of the crosssectional area of a rigid metal conduit of the same trade size unless it is specifically listed for a higher percentage of fill . (e ) Drainage. (1 ) Control Equipment. Where there is a probability that liquid or other condensed vapor may be trapped within enclosures for control equipment or at any point in the raceway system, approved means shall be provided to prevent accumulation or to permit periodic draining of such liquid or condensed vapor. (2 ) Motors and Generators. Where the authority having jurisdiction judges that there is a probability that liquid or condensed vapor may accumulate within motors or generators, joint s and conduit systems shall be arranged to minimize entrance of liquid. If means to prevent accumulation or to permit periodic draining are judged necessary, such means shall be provided at the time of manufacture and shall be considered an integral part of the machine. (3 ) Canned Pumps, Process or Service Connections, Etc. For canned pumps, process or service connections for flow, pressure, or analysis measurement, etc., that depend upon a single compression seal, diaphragm, or tube to prevent flamm able or combustible fluids from entering the electrical conduit system, an additional approved seal, barrier, or other means shall be provided to prevent the flammable or combustible fluid from entering the conduit system beyond the additional devices or means, if the primary seal fails. The additional approved seal or barrier and the interconnecting enclosure shall meet the temperature and pressure conditions to which they will be subjected upon failure of the primary seal, unless other approved means a re provided to accomplish the purpose above. (14-368) 505-18. Conductors and Conductor Insulation. 1) For Type of Protection "e", field wiring conductors shall be copper. (14-365) 2) Where condensed vapors or liquids may collect on, or come in contact with, the insulation on conductors, such insulation shall be of a type approved for use under such conditions; or the insulation shall be protected by a sheath of lead or by other approved means. (14-181) 505-19. Live Parts. T here shall be no exposed live parts .( 14-188) 505-20. Equipment (a) Zone 0. In Class I, Zone 0 locations, only equipment specifically listed and marked as suitable for the location shall be permitted. Exception: Intrinsically safe equipment listed for use in Class I, Division 1 locations for the same gas, or as permitted by Section 505-7(d), and with a suitable temperature classification rating shall be permitted. (b) Zone 1. In Class I, Zone 1 locations, only equipment specifically listed and marked as suitable for the location shall be permitted. Exception: Equipment approved for use in Class I, Division 1 or listed for use in Class I, Zone 0 locations for the same gas, or as permitted by Section 505-7(d) and with a suitable temperature classification rating shall be permitted. (c) Zone 2. In Class I, Zone 2 locations, only equipment specifically listed and marked as suitable for the location shall be permitted. Exception No. 1: Equipment listed for use in Class I, Zone 0 or Zone 1 locations for the same gas, or as permitted by Section 505-7(d), and with a suitable temperature classificationrating, shall be permitted. Exception No. 2: Equipment approved for use in Class I, Division 1 or Division 2 locations for the same gas, or as permitted by Section 505-7(d), and with a suitable temperature classification rating shall be permitted. Exception No. 3: In Class I, Zone 2 locations, the installation of open or nonexplosionproof or nonflameproof enclosed motors, such as squirrel-cage induction motors without brushes, switching mechanisms, or similar arc-producing devices that are not identified for use in a Class I, Zone 2 location shall be permitted. FPN No. 1: It is important to consider the temperature of internal and external surfaces that may be exposed to the flammable atmosphere. FPN No. 2: It is important to consider the risk of ignition due to currents arcing across discontinuities and overheating of parts in multisection enclosures of large motors and generators. Such motors and generators may need equipotential bonding jumpers across joints in the enclosure and from enclosure to ground. Where the presence of ignitible gases or vapors is suspected, clean air purging may be needed immediately prior to and during start-up periods. (d) Manufacturer's Instructions. Electrical equipment installed in hazardous (classified) locations shall be installed in accordance with the instructions (if any) provided by the manufacturer. 505-2.Mult iwire Branch Circuits . In a Class I , Zone 1 location, a multiwire branch circuit shall not be permitted. Exception: Where the disconnect device(s) for the circuit opens all ungrounded conductors of the multiwire circuit simultaneously.

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505-21. Increased Safety "e" Motors and Generators. In Class I, Zone 1 locations, Increased Safety "e" motors and generators of all voltage ratings shall be listed for Class I, Zone 1 locations, and shall comply with the following. 1. Motors shall be marked with the current ratio, IA/IN, and time, tE; 2. Motors shall have controllers marked with the model or identification number, output rating (horsepower or kilowatt), fullload amperes, starting current ratio (IA/IN), and time (tE) of the motors that they are intended to protect; the controller marking shall also include the specific overload protection type (and setting, if applicable) that is listed with the motor or generator; 3. Connections shall be made with the specific terminals listed with the motor or generator; 4. Terminal housings shall be permitted to be of substantial, nonmetallic, nonburning material provided an internal grounding means between the motor frame and the equipment grounding connection is incorporated within the housing; 5. The provisions of Part C of Article 430 shall apply regardless of the voltage rating of the motor; 6. The motors shall be protected against overload by a separate overload device that is responsive to motor current. This device shall be selected to trip or shall be rated in accordance with the listing of the motor and its overload protection; 7. Sections 430-34 and 430-44 shall not apply to such motors; and 8. The motor overload protection shall not be shunted or cut out during the starting period. 505-25. Grounding and Bonding. Grounding and bonding shall comply with Article 250 and the following additional requirements. (a) Bonding. The locknut -bushing and double-locknut types of contacts shall not be depended on for bonding purposes, but bonding jumpers with proper fit tings or other approved means of bonding shall be used. Such means of bonding shall apply to all intervening raceways, fittings, boxes, enclosures, etc., between Class I locations and the point of grounding for service equipment or point of grounding of a separately derived system. Exception: The specific bonding means shall only be required to the nearest point where the grounded circuit conductor and the grounding electrode are connected together on the line side of the building or structure disconnec ting means as specified in Sections 250-32(a), (b), and (c), provided the branch-circuit overcurrent protection is located on the load side of the disconnecting means. FPN: See Section 250-100 for additional bonding requirements in hazardous (classified) locations. (b) Types of Equipment Grounding Conductors. Where flexible metal conduit or liquidtight flexible metal conduit is used as permitted in Section 505-15(c) and is to be relied on to complete a sole equipment grounding path, it shall be insta lled with internal or external bonding jumpers in parallel with each conduit and complying with Section 250-102. Exception: In Class I, Zone 2 locations, the bonding jumper shall be permitted to be deleted where all the following conditions are met. a. Listed liquidtight flexible metal conduit 6 ft (1.83 m) or less in length, with fittings listed for grounding, is used. b. Overcurrent protection in the circuit is limited to 10 amperes or less. c. The load is not a power utilization load. SUBSTANTIATION: This complete revision of Article 505 editorially revises the text to make it more easily understood and also incorporates numerous technical and editorial improvements made via other proposals. PANEL ACTION: Accept. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban COMMENT ON AFFIRMATIVE: BRIESCH: While the Panel Action to accept the rewrite of Article 505 is supported, the NFPA-Circulated Panel Proposal does not include all of the changes agreed to at the meeting. The e-mail sent by Dave Wechsler subsequent to the meeting is more complete in reflecting the Panel Actions from the meeting regarding all but one issue. This e-mail includes changes to Section 505-9(a)(1), 505-20(b), and 505-20(c) that removed the requirement for listed equipment in Zone 1 and Zone 2 locations. These changes were not discussed and agreed to by the Panel at the meeting.

Copyright 2000, NFPA

COOK: I agree with Proposal 14-318a and the substantiation, however, it does not incorporate all of the changes made via other proposals. An updated version that was emailed from Dave Wechsler on 1-26-2000 seems to be more complete with respect to including Panel Actions from the meeting in Hilton Head. The Wechsler versions do include changes in Sections 505-20(b) and (c) that change "listed" to "identified". That thought is completely different than the proposals to change "approved" to "identified". This is a much less restrictive requirement than the current NEC that was not discussed or voted on by the panel. I would be very opposed to this change. See my comments on Proposal 14-2a for use of the term "unclassified." Other changes seem to follow Panel Actions. ENGLER: Not all of the changes made it into the draft circulated with this ballot, vote is to affirm the text with all of the necessary changes made to it. GOODMAN: Generally, I agree with the format and arrangement changes. However, in the new Section 505-2 Definitions, the term "Nonhazardous" has been included. This comment recommends the removal of this term, definition, and use for the following reasons: 1. This term was added as part of the Panel Chairman assigned Task Group responsible for reorganizing the information in Article 505. This term and definition are new material and beyond the scope of the Panel Chair's direction. 2. The added term and definition was not part of any proposal made to the Panel and has no substantiation for its inclusion. 3. This term adds an additional area classification location that does not currently exist in related standards and practices (API 505 for example) or in most company documentation systems. 4. The term is misleading. The implication of "nonhazardous" is that there are no hazards. There are hazards other than electrical area classification such as caustics, acids, radiation, etc. Using the term "unclassified" is becoming widely accepted and recognized as specific to electrical area classification. "Nonhazardous" is much too broad. 5. The term is not needed. An area is either "Classified", requiring specifically identified or approved equipment suitable for the location or "Unclassified", not requiring equipment so identified or approved. The term will only add confusion and potential misapplication. 6. By its definition, "Nonhazardous Locations. Locations which are not required to have been evaluated". Whoever makes the determination that the location is not required to be evaluated has just evaluated the location. It is also not at all clear how or who would make that determination. For the above reasons, the term "Nonhazardous", its definition and use should be removed from Article 505 (and 500). JAGUNICH: See ballot for David Wechsler. LAWRENCE: Due the the large number of public proposals received and acted upon, and also due to time constraints, the panel was not able to compile and correlate all aspects of the rewrites of the affected article. Please see David Wechsler's ballot. OMEARA: Please see the comments on the ballot for David Wechsler. WECHSLER: While attempts were made to provide NFPA Staff with corrected revisions of this text before the end of the CMP 14 panel meeting, a detailed review of this balloted draft versions has indicated that this does not correctly reflect the panel actions. Additionally, there is conflicting information in several panel action statements that indicates that this text applies to Article 505 and to Article 501. In fact there are panel action rewrites to both Article 505, 501 and 502. We attribute the problems with this draft to the following: a) the use of several earlier drafts that were consistently being revised to keep pace with changes made due to committee actions on public proposals. b) the limited time available to proof and develop this work, c) the extremely large number of public proposals, d) the complex nature of the interaction of affected texts within Articles 500, 501, 502 and 505, and the desire of the panel to maintain consistency, and e) human errors in transcribing this information. The following text provides a correct revision of this complete work effort for Article 505. This text should be the committee document of record and not that provided with the panel ballot. ARTICLE 505 -- Class I, Zone 0, 1, and 2 Locations 505-1. Scope [unchanged] This article covers the requirements for the zone classification system as an alternative to the division classification system covered in Article 500 for electrical and electronic equipment and wiring

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for all voltages in Class I, Zone 0, Zone 1, and Zone 2 hazardous (classified) locations where fire or explosion hazards may exist due to flammable gases, vapors, or liquids. FPN: For the requirements for electrical and electronic equipment and wiring for all voltages in Class I, Division 1 or Division 2; Class II, Division 1 or Division 2; and Class III, Division 1 or Division 2 hazardous (classified) locations where fire or explosion hazards may exist due to flammable gases or vapors, flammable liquids, or combustible dusts or fibers, refer to Articles 500 through 504. [new] 505-2 Definitions. For purposes of this article, the following definitions apply. [14-320 ,CP140x] Identified (as applied to equipment). Recognizable as suitable for the specific purpose, function, use, environment, application, etc., where prescribed in a particular Code requirement. FPN: Suitability of equipment for a specific purpose, environment, or application may be determined by: 1.4. equipment listing or labeling; 2. evidence of equipment evaluation from a qualified testing laboratory or inspection agency concerned with product evaluation; or 3. other evidence acceptable to the authority having jurisdiction such as a manufacturer's self evaluation or an owner's engineering judgment. (See definitions of Labeled and Listed ) [CP140?-500 rewrite, Panel action Cook actions, correlation w/500] Unclassified Locations . Locations that have been evaluated by the classification process defined in Section 500-3 5(a) or Section 505-3 5 (a) and determined to be neither Class I, Division 1; Class I, Division 2; Class I, Zone 0; Class I, Zone 1; Class I, Zone 2; Class II, Division 1; Class II, Division 2; Class III, Division 1; Class III, Division 2; or any combination thereof. [14323, CP140x] Nonhazardous Locations. Locations which are not required to have been evaluated by the process defined in 500-3 5 (a) or 505-3 5 (a). [CP140x] Electrical and Electronic Equipment. Materials, fittings, devices, appliances, and the like that are part of, or in connection with an electrical installation, as well as any portable or transportable device having a battery or other electrical power source. (14-6) Flameproof. Type of protection where the enclosure will withstand an internal explosion of a flammable mixture that has penetrated into the interior, without suffering damage and without causing ignition, through any joints or structural openings in the enclosure, of an external explosive gas atmosphere consisting of one or more of the gases or vapors for which it is designed. FPN: See Electrical Apparatus for Use In Class I, Zone 1 and 2 Hazardous (Classified) Locations, Type of Protection -- Flameproof "d," ISA S12.22.01-1996; Electrical Apparatus for Explosive Gas Atmospheres, Part 1 -- Construction and Verification Test of Flameproof Enclosures of Electrical Apparatus, IEC 79-1-1990 and Amendment No. 1 (1993). Purged and Pressurized. Type of protection for electrical equipment that uses the technique of guarding against the ingress of the external atmosphere, which may be explosive, into an enclosure by maintaining a protective gas therein at a pressure above that of the external atmosphere. FPN No. 1: See Standard for Purged and Pressurized Enclosures for Electrical Equipment, NFPA 496-1998. FPN No. 2: See Electrical Apparatus for Explosive Gas Atmospheres - Part 2: Electrical Apparatus, Type of Protection "p," IEC 79-2-1983; and Electrical Apparatus for Explosive Gas Atmospheres - Part 13: Construction and Use of Rooms or Buildings Protected by Pressurization, IEC 79-13-1982. Intrinsic Safety. Type of protection where any spark or thermal effect is incapable of causing ignition of a

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mixture of flammable or combustible material in air under prescribed test conditions. FPN No. 1: See Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I, II, and III, Hazardous Locations, ANSI/UL 913-1997; Electrical Apparatus for Explosive Gas Atmospheres -- Part 11: Intrinsic Safety "i," IEC 60079-11-1999. FPN No. 2: Intrinsic safety is designated type of protection "ia" by IEC 79-11 for use in Zone 0 locations. Intrinsic safety is designated type of protection "ib" by IEC 79-11 for use in Zone 1 locations. FPN No. 3: Intrinsically safe associated apparatus, designated by [ia] or [ib], is connected to intrinsically safe equipment ("ia" or "ib" respectively), but is located outside the hazardous (classified) location unless also protected by another type of protection (such as flameproof). Type of Protection "n." Type of protection where electrical equipment, in normal operation, is not capable of igniting a surrounding explosive gas atmosphere and a fault capable of causing ignition is not likely to occur. FPN: see Electrical Apparatus for Explosive Gas Atmospheres, Part 15 -- Electrical Apparatus with Type of Protection "n," IEC 79-15-1987. Oil Immersion "o." Type of protection where electrical equipment immersed in a protective liquid in such a way that an explosive atmosphere that may be above the liquid or outside the enclosure cannot be ignited. FPN: See Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations, Type of Protection -- Oil-Immersion "o," ISA S12.26.01 -- 1996; and Electrical Apparatus for Explosive Gas Atmospheres, Part 6 -- Oil-Immersion "o," IEC 79-6-1995. Increased Safety "e." Type of protection where electrical equipment that does not produce arcs or sparks in normal service and under specified abnormal conditions, in which additional measures are applied so as to give increased security against the possibility of excessive temperatures and of the occurrence of arcs and sparks. FPN: See Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations, Type of Protection -- Increased Safety "e," ISA S12.16.01-1996; and Electrical Apparatus for Explosive Gas Atmospheres -- Part 7: Increased Safety "e," IEC 79-7-1990, Amendment No. 1 (1991), and Amendment No. 2 (1993). Encapsulation "m." Type of protection where electrical parts that could ignite an explosive atmosphere by either sparking or heating are enclosed in a compound in such a way that this explosive atmosphere cannot be ignited. FPN: See Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations Type of Protection -- Encapsulation "m," ISA S12.23.01-1996, and Electrical Apparatus for Explosive Gas Atmospheres -- Part 18: Encapsulation "m," IEC 79-18-1992. Powder Filling "q." Type of protection where electrical parts capable of igniting an explosive atmosphere are fixed in position and completely surrounded by filling material (glass or quartz powder) to prevent the ignition of an external explosive atmosphere. FPN: See Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations Type of Protection -- Powder Filling "q," ISA S12.25.01-1996, and Electrical Apparatus for Explosive Gas Atmospheres -- Part 5: Powder Filling, Type of Protection "q," IEC 79-5-1967.

505-32. [505-2] Other Articles All other applicable rules contained in this Code shall apply to electrical equipment and wiring installed in hazardous (classified) locations. Exception: As modified by Article 504 and this article. 505-3 4 General (a) [505-10 (c)] Documentation for Industrial Occupancies.

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All areas in industrial occupancies designated as hazardous (classified) locations shall be properly documented. This documentation shall be available to those authorized to design, install, inspect, maintain, or operate electrical equipment at the location. FPN: For examples of area classification drawings, see Electrical Apparatus for Explosive Gas Atmospheres, Classification of Hazardous Areas, IEC 79-10-1995; Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Zone 0, Zone 1, or Zone 2, API RP 505-1997; Electrical Apparatus for Explosive Gas Atmospheres, Classifications of Hazardous (Classified) Locations, ISA S12.24.01-1997; Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Division I or Division 2, API RP 5001997, Model Code of Safe Practice in the Petroleum Industry, Part 15: Area Classification Code for Petroleum Installations, IP 15, The Institute of Petroleum, London. (b) [505-5] Reference Standards. FPN No. 1: It is important that the authority having jurisdiction be familiar with recorded industrial experience as well as with standards of the National Fire Protection Association, the American Petroleum Institute, and the International Society for Measurement and Control (ISA), that may be of use in the classification of various locations, the determination of adequate ventilation, and the protection against static electricity and lightning hazards. FPN No. 2: For further information on the classification of locations, see Electrical Apparatus for Explosive Gas Atmospheres, Classification of Hazardous Areas, IEC 7910-1995; Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Zone 0, Zone 1, or Zone 2, ANSI/ API RP 505-19976; Electrical Apparatus for Explosive Gas Atmospheres, Classifications of Hazardous (Classified) Locations, ISA S12.24.01-1997; and Model Code of Safe Practice in the Petroleum Industry, Part 15: Area Classification Code for Petroleum Installations, IP 15, The Institute of Petroleum, London. FPN No. 3: For further information on protection against static electricity and lightning hazards in hazardous (classified) locations, see Recommended Practice on Static Electricity, NFPA 77-1993; Standard for the Installation of Lightning Protection Systems, NFPA 7801997; and Protection Against Ignitions Arising Out of Static Lightning and Stray Currents, API RP 2003-1991. FPN No. 4: For further information on ventilation, see Flammable and Combustible Liquids Code, NFPA 301996, and Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Division 1 or Division 2, API RP 500-1997, Section 6.3. FPN No. 5: For further information on electrical systems for hazardous (classified) locations on offshore oil and gas producing platforms, see Recommended Practice for Design and Installation of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassifed and Class I, Zone 0, Zone 1, and Zone 2 LocationsProduction Platforms, ANSI/API RP 14FZ20001991. FPN No. 6: For further information on the installation of electrical equipment in hazardous (classified) locations in general, see Electrical Apparatus for Explosive Gas Atmospheres -- Part 14: Electrical Installations in Explosive Gas Atmospheres (Other than Mines), IEC 7914-1996, and Electrical Apparatus for Explosive Gas Atmospheres -- Part 16: Artificial Ventilation for the Protection of Analyzer(s) Houses, IEC 79-16-1990. 505-4 5 Classifications of Locations (a) [505-3(a)]Classification of Locations. Locations shall be classified depending on the properties of the flammable vapors, liquids, or gases that may be present and the likelihood that a flammable or combustible concentration or quantity is present. Where pyrophoric materials are the only materials used or handled, these locations shall not be classified.

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Each room, section, or area shall be considered individually in determining its classification. FPN No. 1: See Section 505-6 7 for restrictions on area classification. FPN No. 2: Through the exercise of ingenuity in the layout of electrical installations for hazardous (classified) locations, it is frequently possible to locate much of the equipment in reduced level of classification or in an unclassified location less hazardous or in nonhazardous locations and, thus, to reduce the amount of special equipment required. [14-323] Rooms and areas containing ammonia refrigeration systems that are equipped with adequate mechanical ventilation, may be classified as "unclassified" locations. FPN: For further information regarding classification and ventilation of areas involving ammonia, see Safety Code for Mechanical Refrigeration, ANSI/ASHRAE 15-1994, and Safety Requirements for the Storage and Handling of Anhydrous Ammonia, ANSI/CGA G2.1-1989 (14-39) (b) Class I Zone Locations. Class I Zone locations are those in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitible mixtures. Class I Zone locations shall include those specified in (1), (2) and (3). (1) [505-9 (a)] Class I, Zone 0 . A Class I, Zone 0 location is a location (a) [505-9 (a) (1)] In which ignitible concentrations of flammable gases or vapors are present continuously, or (b) [505-9 (a) (2)] In which ignitible concentrations of flammable gases or vapors are present for long periods of time. FPN No. 1: As a guide in determining when flammable gases or vapors are present continuously or for long periods of time, refer to Recommended Practice for Classification of Locations for Electrical Installations of Petroleum Facilities Classified as Class I, Zone 0, Zone 1 or Zone 2, API RP 505-1996; Electrical Apparatus for Explosive Gas Atmospheres, Classifications of Hazardous Areas, IEC 79-10-1995; and Area Classification Code for Petroleum Installations, Model Code, Part 15, Institute of Petroleum; and Electrical Apparatus for Explosive Gas Atmospheres, Classifications of Hazardous (Classified) Locations, ISA S12.24.01-1997. FPN No. 2: This classification includes locations inside vented tanks or vessels that contain volatile flammable liquids; inside inadequately vented spraying or coating enclosures, where volatile flammable solvents are used; between the inner and outer roof sections of a floating roof tank containing volatile flammable liquids; inside open vessels, tanks and pits containing volatile flammable liquids; the interior of an exhaust duct that is used to vent ignitible concentrations of gases or vapors; and inside inadequately ventilated enclosures that contain normally venting instruments utilizing or analyzing flammable fluids and venting to the inside of the enclosures. FPN No. 3: It is not good practice to install electrical equipment in Zone 0 locations except when the equipment is essential to the process or when other locations are not feasible. [See Section 505-3(a) FPN No. 2.] If it is necessary to install electrical systems in a Zone 0 location, it is good practice to install intrinsically safe systems as described by Article 504. (2) [505-9 (b)] Class I, Zone 1 . A Class I, Zone 1 location is a location (a) [505-9 (b) (1)] In which ignitible concentrations of flammable gases or vapors are likely to exist under normal operating conditions; or (b) [505-9 (b) (2)] In which ignitible concentrations of flammable gases or vapors may exist frequently because of repair or maintenance operations or because of leakage; or (c) [505-9 (b) (3)] In which equipment is operated or processes are carried on, of such a nature that equipment breakdown or faulty operations could result in the release of ignitible concentrations of flammable gases or vapors and also cause simultaneous failure of electrical equipment in a mode to cause the electrical equipment to become a source of ignition; or

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(d) [5 05-9 (b) (4)] That is adjacent to a Class I, Zone 0 location from which ignitible concentrations of vapors could be communicated, unless communication is prevented by adequate positive pressure ventilation from a source of clean air and effective safeguards against ventilation failure are provided. FPN No. 1: Normal operations is considered the situation when plant equipment is operating within its design parameters. Minor releases of flammable material may be part of normal operations. Minor releases include the releases from mechanical packings on pumps. Failures that involve repair or shutdown (such as the breakdown of pump seats and flange gaskets, and spillage caused by accidents) are not considered normal operation. FPN No. 2: This classification usually includes locations where volatile flammable liquids or liquefied flammable gases are transferred from one container to another. In areas in the vicinity of spraying and painting operations where flammable solvents are used; adequately ventilated drying rooms or compartments for evaporation of flammable solvents; adequately ventilated locations containing fat and oil extraction equipment using volatile flammable solvents; portions of cleaning and dyeing plants where volatile flammable liquids are used; adequately ventilated gas generator rooms and other portions of gas manufacturing plants where flammable gas may escape; inadequately ventilated pump rooms for flammable gas or for volatile flammable liquids; the interiors of refrigerators and freezers in which volatile flammable materials are stored in the open, lightly stoppered, or easily ruptured containers; and other locations where ignitible concentrations of flammable vapors or gases are likely to occur in the course of normal operation, but not classified Zone 0. (3) [505-9 (c)] Class I, Zone 2 . A Class I, Zone 2 location is a location (a) [505-9 (c) (1)] In which ignitible concentrations of flammable gases or vapors are not likely to occur in normal operation and if they do occur will exist only for a short period; or (b) [505-9 (c) (2)] In which volatile flammable liquids, flammable gases, or flammable vapors are handled, processed, or used, but in which the liquids, gases, or vapors normally are confined within closed containers of closed systems from which they can escape, only as a result of accidental rupture or breakdown of the containers or system, or as a result of the abnormal operation of the equipment with which the liquids or gases are handled, processed, or used; or (c) [505-9 (c) (3)] In which ignitible concentrations of flammable gases or vapors normally are prevented by positive mechanical ventilation, but which may become hazardous as a result of failure or abnormal operation of the ventilation equipment; or (d) [505-9 (c) (4)] That is adjacent to a Class I, Zone 1 location, from which ignitible concentrations of flammable gases or vapors could be communicated, unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air, and effective safeguards against ventilation failure are provided. FPN: The Zone 2 classification usually includes locations where volatile flammable liquids or flammable gases or vapors are used, but which would become hazardous only in case of an accident or of some unusual operating condition. 505-5 6 [505-7] Material Groups [505-7] For purposes of testing, approval, and area classification, various air mixtures (not oxygen enriched) shall be grouped as required in (a), (b), and (c). FPN: Group I is intended for use in describing atmospheres that contain firedamp (a mixture of gases, composed mostly of methane, found underground, usually in mines). This Code does not apply to installations underground in mines. See Section 90-2(b). Group II shall be subdivided into IIC, IIB, and IIA, as noted in (a), (b), and (c), according to the nature of the gas or vapor, for protection techniques "d," "ia," "ib," "[ia]," and "[ib]," and, where applicable, "n" and "o." FPN No. 1: The gas and vapor subdivision as described above is based on the maximum experimental safe gap (MESG), minimum igniting current (MIC), or both. Test equipment for determining the MESG is described in Construction and Verification Tests of Flameproof

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Enclosures of Electrical Apparatus, IEC 79-1A-1975, Amendment No. 1 (1993) and UL Technical Report No. 58 (1993). The test equipment for determining MIC is described in Spark-Test Apparatus for Intrinsically-Safe Circuits, IEC 79-3-1990. The classification of gases or vapors according to their maximum experimental safe gaps and minimum igniting currents is described in Classification of Mixtures of Gases or Vapours with Air According to Their Maximum Experimental Safe Gaps and Minimum Igniting Currents, IEC 79-12-1978. FPN No. 2: Verification of electrical equipment utilizing protection techniques "e," "m," "p," and "q," due to design technique, does not require tests involving MESG or MIC. Therefore, Group II is not required to be subdivided for these protection techniques. FPN No. 3: It is necessary that the meanings of the different equipment markings and Group II classifications be carefully observed to avoid confusion with Class I, Divisions 1 and 2, Groups A, B, C, and D.

(a) Class I Zone Group Classifications. Class I Zone groups shall be as follows: (1) [505-7 (a)] x Group IIC. Atmospheres containing acetylene, hydrogen, or flammable gas, flammable liquid-produced vapor, or combustible liquid-produced vapor mixed with air that may burn or explode, having either a maximum experimental safe gap (MESG) value less than or equal to 0.50 mm or minimum igniting current ratio (MIC ratio) less than or equal to 0.45. FPN: Group IIC is equivalent to a combination of Class I, Group A, and Class I, Group B, as described in Sections 500-6 (a) (1) 5(a)(1) and 6 (a) (2) (a)(2). (2) [505-7 (b)] x Group IIB. Atmospheres containing acetaldehyde, ethylene, or flammable gas, flammable liquid-produced vapor, or combustible liquid-produced vapor mixed with air that may burn or explode, having either maximum experimental safe gap (MESG) values greater than 0.50 mm and less than or equal to 0.90 mm or minimum igniting current ratio (MIC ratio) greater than 0.45 and less than or equal to 0.80. FPN: Group IIB is equivalent to Class I, Group C, as described in Section 500-6 5(a)(3). (3) [505-7 (c)] x Group IIA. Atmospheres containing acetone, ammonia, ethyl alcohol, gasoline, methane, propane, or flammable gas, flammable liquid-produced vapor, or combustible liquid-produced vapor mixed with air that may burn or explode, having either a maximum experiment safe gap (MESG) value greater than 0.90 mm or minimum igniting current ratio (MIC ratio) greater than 0.80. FPN: Group IIA is equivalent to Class I, Group D as described in Section 500-6 5(a)(4). 505-6 7 [505-6] Special Precaution Article 505 requires equipment construction and installation that will ensure safe performance under conditions of proper use and maintenance. FPN No. 1: It is important that inspection authorities and users exercise more than ordinary care with regard to the installation and maintenance of electrical equipment in hazardous (classified) locations. FPN No. 2: Low ambient conditions require special consideration. Electrical equipment depending on the protection techniques described by Section 505- 8 (a) 4(a) may not be suitable for use at temperatures lower than -20ºC (-13ºF) unless they are approved for use at lower temperatures. However, at low ambient temperatures, flammable concentrations of vapors may not exist in a location classified Class I, Zones 0, 1, or 2 at normal ambient temperature. (a) [505-6(a)] Supervision of Work. Classification of areas and selection of equipment and wiring methods shall be under the supervision of a qualified Registered Professional Engineer. (14348) (ab) [505-6(b)] Dual Classification. In instances of areas within the same facility classified separately, Class I, Zone 2 locations shall be permitted to abut, but not overlap, Class I, Division 2 locations.

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Class I, Zone 0 or Zone 1 locations shall not abut Class I, Division 1 or Division 2 locations. (b c) [505-6(c)] Reclassification Permitted. A Class I, Division 1 or Division 2 location shall be permitted to be reclassified as a Class I, Zone 0, Zone 1, or Zone 2 location provided all of the space that is classified because of a single flammable gas or vapor source is reclassified under the requirements of this article. (c ) Solid Obstacles. Flameproof equipment with flanged joints shall not be installed such that the flange openings are closer than the distances shown in Table 505-7 505-15 to any solid obstacle that is not a part of the equipment (such as steelworks, walls, weather guards, mounting brackets, pipes, or other electrical equipment) unless the equipment is listed for a smaller distance of separation. [14-364] Table 505- 7 15. Minimum Distance of Obstructions from Flameproof "d" Flange Openings Minimum Distance In. 1 37/64 1 3/16 25/64 Minimum Distance Mm 40 30 10

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(2) [ 505-7(d)] Equipment shall be permitted to be listed for a specific gas or vapor, specific mixtures of gases or vapors, or any specific combination of gases or vapors. FPN: One common example is equipment marked for "IIB + H2." (b) [505-10(b)] Marking Equipment shall be marked in accordance with (1) or (2). (1) [505-10(b)(1)] Division Equipment. Equipment identified approved for Class I, Division 1 or Class I, Division 2 shall, in addition to being marked in accordance with Section 500-56(d), be permitted to be marked with the following: a. Class I, Zone 1 or Class I, Zone 2 (as applicable), and b. Applicable gas classification group(s) in accordance with Table 505-89(b)(2), and c. Temperature classification in accordance with Section 505-8 9(3) (2) [505-10(b)(2)] Zone Equipment. Equipment meeting one or more of the protection techniques described in Section 505-4 5 shall be marked with the following in the order shown: a. Class b. Zone c. Symbol "AEx" d. Protection technique(s) in accordance with Table 505-89(b)(2) e. Applicable gas classification group(s) in accordance with Table 505-89(b)(2) f. Temperature classification in accordance with Section 505-89(c) Exception: Intrinsically safe associated apparatus shall be required to be marked only with (c), (d), and (e). FPN No. 1: An example of such a required marking is "Class I, Zone 0, AEx ia IIC T6." Electrical equipment of types of protection "e," "m," "p," or "q," shall be marked Group II. Electrical equipment of types of protection "d," "ia," "ib," "[ia]," or "[ib]" shall be marked Group IIA, or IIB, or IIC, or for a specific gas or vapor. Electrical equipment of types of protection "n" shall be marked Group II unless it contains enclosedbreak devices, nonincendive components, or energylimited equipment or circuits, in which case it shall be marked Group IIA, IIB, or IIC, or a specific gas or vapor. Electrical equipment of other types of protection shall be marked Group II unless the type of protection utilized by the equipment requires that it shall be marked Group IIA, IIB, or IIC, or a specific gas or vapor. FPN No. 2: An explanation of the marking that is required follows.

Gas Group IIC IIB IIA

505- 7 8 [505-4] Protection Techniques The following shall be acceptable protection techniques for electrical and electronic equipment in hazardous (classified) locations. FPN: For additional information, see Electrical Apparatus for Use in Class I, Zone 0, 1 Hazardous (Classified) Locations General Requirements, ISA S12.0.01-1997; Electrical Equipment for Use in Class I, Zone 0, 1, and 2 Hazardous (Classified) Locations, ANSI/UL 2279, 1997; and Electrical Apparatus for Explosive Gas Atmospheres - Part 0: General Requirements, IEC 79-0-1983, Amendment No. 1 (1987), and Amendment No. 2 (1991). (a)(b) [505-4(a)] Flameproof "d." This protection technique shall be permitted for equipment in Class I, Zone 1 or Zone 2 locations. (b) [505-4(b)] Purged and Pressurized. This protection technique shall be permitted for equipment in those Class I, Zone 1 or Zone 2 locations for which it is approved. (c) [505-4(c)] Intrinsic Safety. This protection technique shall be permitted for equipment in Class I, Zone 0 or Zone 1 locations for which it is approved. (d) [505-4(d)] Type of Protection "n." This protection technique shall be permitted for equipment in Class I, Zone 2 locations. Type of protection "n" is further subdivided into nA, nC, and nR. FPN: See Table 505-9(b) (1) 505-10(b) 1 for the descriptions of subdivisions for type of protection "n." (e) [505-4(e)] Oil Immersion "o." This protection technique shall be permitted for equipment in Class I, Zone 1 locations. (f) [505-4(f)] Increased Safety "e." This protection technique shall be permitted for equipment in Class I, Zone 1 locations. (g) [505-4(g )] Encapsulation "m." This protection technique shall be permitted for equipment in Class I, Zone 1 locations. (h) [505-4(h)] Powder Filling "q." This protection technique shall be permitted for equipment in Class I, Zone 1 locations. 505-8 9 Equipment (a) [505-10 (a)] Listing. (1) Equipment that is listed for a Zone 0 location shall be permitted in a Zone 1 or Zone 2 location of the same gas or vapor. Equipment that is identified listed for a Zone 1 location shall be permitted in a Zone 2 location of the same gas or vapor.

Figure 505-8 9(b)(1) [505-10(b) (1) ] .

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Table 505-8 9(b)(1). Types of Protection Designation

Designation d e ia ib [ia] [ib] m nA nC Technique Flameproof enclosure Increased safety Intrinsic safety Intrinsic safety Intrinsically safe associated apparatus Intrinsically safe associated apparatus Encapsulation Nonsparking equipment Sparking equipment in which the contacts are suitably protected other than by restricted breathing enclosure Restricted breathing enclosure Oil immersion Purged and pressurized Powder filled Zone* 1 1 0 1 Unclassified or Nonhazardous Unclassified or Nonhazardous 1 2 2

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together with the special range of ambient temperatures. As an example, such a marking might be "-30ºC Ta + 40ºC." Electrical equipment suitable for ambient temperatures exceeding 40ºC (104ºF) shall be marked with both the maximum ambient temperature and the operating temperature or temperature range class at that ambient temperature. Exception No. 1: Equipment of the nonheat-producing type, such as conduit fittings, and equipment of the heat-producing type having a maximum temperature of not more than 100ºC (212ºF) shall not be required to have a marked operating temperature or temperature range class. Exception No. 2: Equipment approved for Class I, Division 1 or Division 2 locations as permitted by Sections 505-20(b) and (c) shall be permitted to be marked in accordance with Section 500-56(d) and Table 500-5 6(d). (d) [505-3(b))] Threading All threaded conduit referred to herein shall be threaded with an National (American) Standard Pipe Taper (NPT ) standard conduit cutting die that provides 3/4-in. taper per foot. Such conduit shall be made wrenchtight to prevent sparking when fault current flows through the conduit system, and to ensure the explosionproof or flameproof integrity of the conduit system where applicable. Threaded joints shall be made up with at least five threads fully engaged. Equipment provided with threaded entries for field wiring connections shall be installed in accordance with (1) or (2). (1) Equipment Provided with Threaded Entries for NPT Threaded Conduit or Fittings. For equipment provided with threaded entries for NPT threaded conduit or fittings, listed conduit, conduit fittings, or cable fittings shall be used. FPN: Threading specifications for NPT threads are located in Pipe Threads, General Purpose (Inch), ANSI /ASME B1.20.1-1983. (2) Equipment Provided with Threaded Entries for Metric Threaded Conduit or Fittings. For equipment with metric threaded entries, such entries shall be identified as being metric, or listed adapters to permit connection to conduit or NPT-threaded fittings shall be provided with the equipment. Adapters shall be used for connection to conduit or NPT-threaded fittings. Listed cable fittings that have metric threads shall be permitted to be used. FPN: Threading specifications for metric threaded entries are located in Metric Screw Threads, ISO 965/1-1980, and Metric Screw Threads, ISO 965/3-1980. 505-15.[505-15][14-364] Wiring Methods. Wiring methods shall maintain the integrity of protection techniques and shall comply with (a), (b), or (c). (a) Class I, Zone 0. In Class I, Zone 0 locations, only intrinsically safe wiring methods in accordance with Article 504 shall be permitted. FPN: Article 504 only includes protection technique " ia."

nR o p q

2 1 1 or 2 1

* Does not address use where a combination of techniques is used. Table 505-8 9(b)(2). [505-10(b)(2)] Gas Classification Groups Gas Group IIC IIB IIA Comment See Section 505-5 6(a) (1) See Section 505-5 6(a) (2)(b) See Section 505-5 6(a)(3 ) (c)

(c) [505-8] Class I Temperature The temperature marking specified below in Section 505-10(b) shall not exceed the ignition temperature of the specific gas or vapor to be encountered. FPN: For information regarding ignition temperatures of gases and vapors, see Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 497-1997; Guide to Fire Hazard Properties of Flammable Liquids, Gases, and Volatile Solids, NFPA 325-1994; and Electrical Apparatus for Explosive Gas Atmospheres, Data for Flammable Gases and Vapours, Relating to the Use of Electrical Apparatus, IEC 79-20-1996. (1) [505-10(b)(3)] Temperature Classifications. Approved equipment shall be marked to show the operating temperature or temperature range class referenced to a 40ºC (104ºF) ambient. The temperature range class , if provided, shall be indicated using the temperature class (T Code) in identification numbers, as shown in Table 505-8 9 (c). Table 505-8 9(c). [505-10(b)(3) ] Classification of Maximum Surface Temperature for Group II Electrical Equipment Temperature Class (T Code) T1 T2 T3 T4 T5 T6 Maximum Surface Temperature (ºC) 450 300 200 135 100 85

(b) Class I, Zone 1. (1) In Class I, Zone 1 locations, the following wiring methods shall be permitted: (a) Type MC-HL cable listed for use in Class I, Zone 1 or Division 1 locations, with a gas/vaportight continuous corrugated metallic sheath, an overall jacket of suitable polymeric material, separate grounding conductors in accordance with Section 250-122, and provided with termination fittings listed for the application. FPN: See Sections 334-3 and 334-4 for restrictions on use of Type MC cable. (b) Type ITC-HL cable, listed for use in Class I, Zone 1 or Division 1 locations, with a gas/vaportight continuous corrugated metallic sheath, an overall jacket of suitable

Electrical equipment designed for use in the ambient temperature range between -20ºC and +40ºC shall require no additional temperature marking. Electrical equipment that is designed for use in a range of ambient temperatures other than -20ºC and +40ºC is considered to be special; and the ambient temperature range shall then be marked on the equipment, including either the symbol "Ta" or "Tamb"

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polymeric material and provided with termination fittings listed for the application. (c) In industrial establishments with restricted public access, where the conditions of maintenance and supervision ensure that only qualified persons will service the installation, and where the cable is not subject to physical damage, Type TC cable shall be permitted if listed as suitable for use as open wiring and provided with a gas/vaportight overall jacket of suitable polymeric material and provided with separate grounding conductors in accordance with Section 250-122. Cable termination fittings shall be listed for the application. The open wiring shall not exceed lengths of 15 feet. FPN: Type TC cable listed for use as open wiring meets the crush and impact requirements of Type MC cable. (d) Type MI cable with termination fittings approved for Class I, Zone 1 or Division 1 locations. Type MI cable shall be installed and supported in a manner to avoid tensile stress at the termination fittings. (e) Th readed rigid metal conduit, or threaded steel intermediate metal conduit. (f) Rigid nonmetallic conduit complying with Article 347 shall be permitted where encased in a concrete envelope a minimum of 2 in. (50.8 mm) thick and provided with not less than 24 in. (610 mm) of cover measured from the top of the conduit to grade. Threaded rigid metal conduit or threaded steel intermediate metal conduit shall be used for the last 24 in. (610 mm) of the underground run to emergence or to the point of connection to the aboveground raceway. An equipment grounding conductor shall be included to provide for electrical continuity of the raceway system and for grounding of noncurrent-carrying metal parts. (2) Where necessary to employ flexible connections, flexible fittings listed for Class I, Zone 1 or Division 1 locations or flexible cord in accordance with the provisions of Section 505-17 shall be permitted. (c) Class I, Zone 2. (1) In Class I, Zone 2 locations, the following wiring methods shall be permitted: (a) Types MI, MC, MV, or TC cable with approved termination fittings, or in cable tray systems and installed in a manner to avoid tensile stress at the termination fittings; (b) Type ITC cable in cable trays, in raceways, supported by messenger wire, afforded mechanical protection and run as open wiring, or directly buried where the cable is listed for this use; (c) Type PLTC cable in accordance with the provisions of Article 725, or in cable tray systems. PLTC shall be installed in a manner to avoid tensile stress at the termination fittings; (d) enclosed gasketed busways, enclosed gasketed wireways; (e) threaded rigid metal conduit, threaded steel intermediate metal conduit; (f) Nonincendive field wiring using any of the wiring methods suitable for n onhazardous locations, including Chapter 7 and 8 wiring methods. (2) Where provision must be made for limited flexibility, flexible metal fittings, flexible metal conduit with approved fittings, liquidtight flexible metal conduit with approved fittings, liquidtight flexible nonmetallic conduit with approved fittings, or flexible cord in accordance with the provisions of Section 505-17 shall be permitted.

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FPN: See Section 505-25(b) for grounding requirements where flexible conduit is used. [new- NFPA che ck formating] 505-16. Sealing and Drainage. Seals in conduit and cable systems shall comply with (a) through (e). Sealing compound shall be used in Type MI cable termination fittings to exclude moisture and other fluids from the cable insulation. FPN No . 1: Seals are provided in conduit and cable systems to minimize the passage of gases and vapors and prevent the passage of flames from one portion of the electrical installation to another through the conduit. Such communication through Type MI cable is inherently prevented by construction of the cable. Unless specifically designed and tested for the purpose, conduit and cable seals are not intended to prevent the passage of liquids, gases, or vapors at a continuous pressure differential across the seal. Even at differences in pressure across the seal equivalent to a few inches of water, there may be a slow passage of gas or vapor through a seal, and through conductors passing through the seal. See Section 505-16( c)(2)(b). Temperature extremes and highly corrosive liquids and vapors can affect the ability of seals to perform their intended function. See Section 50516(d)(2). FPN No. 2: Gas or vapor leakage and propagation of flames may occur through the interstices between the strands of standard stranded conductors larger than No. 2. Special conductor constructions, e.g., compacted strands or sealing of the individual strands, are means of reducing leakage and preventing the propagation of flames. (a) Zone 0. In Class I, Zone 0 locations, seals shall be located as follows. (1) Seals shall be provided within 10 ft (3.05 m) of where a conduit leaves a Zone 0 location. There shall be no unions, couplings, boxes, or fittings, except reducers at the seal, in the conduit run between the seal and the point at w hich the conduit leaves the location. Exception: A rigid unbroken conduit that passes completely through the Zone 0 location with no fittings less than 12 in. (305 mm) beyond each boundary, shall not be required to be sealed, if the termination pointsthe unbroken conduit are in of unclassified locations. (2) Seals shall be provided on cables at the first point of termination after entry into the Zone 0 location. (3) Seals shall not be required to be explosionproof or flameproof. (b) Zone 1. In Class I, Zone 1 locations, seals shall be located as follows. (1) Conduit seals shall be provided for each conduit entering enclosures having type of protection `d' or `e'. Exception: Where the enclosure having type of protection `d' is marked to indicate a seal is not required. that (2) Conduit seals shall be provided for each conduit entering explosionproof equipment as follows. a. In each conduit entry into an explosionproof enclosure where either (1) the enclosure contains apparatus, such as switches, circuit breakers, fuses, relays, or resistors, that may produce arcs, sparks, or high temperatures that are considered to be an ignition source in normal operation, or (2) the entry is 2-in. size or larger and the enclosure contains terminals, splices, or taps. For the purposes of this section high temperatures shall be considered to be any temperatures exceeding 80 percent of the

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autoignition temperature in degrees Celsius of the gas or vapor and twisted pair cables, it shall not be required to remove the involved. shielding material or separate the twisted pair. Exception: Conduit entering an enclosure where such switches, circuit breakers, fuses, relays, or (6) Each multiconductor cable in conduit shall be considered as a resistors are single conductor if the cable is incapable of tra nsmitting gases or 1. Enclosed within a chamber vapors through the cable core. These cables shall be sealed in hermetically sealed against the entrance accordance with (d). of gases or vapors, or 2. Immersed in oil, or (7) Cable seals shall be provided for each cable entering 3. Enclosed within a factory-sealed flameproof or explosionproof enclosures. The seal shall comply explosionproof chamber located within the with (d). enc losure, approved for the location, and marked "factory sealed" or equivalent. (8) Cables shall be sealed at the point at which they leave the Zone Factory-sealed enclosures shall not 1 location. be considered to serve as a seal for Exception: Where cable is sealed at the termination point. another adjacent explosionproof enclosure that is required to have a (c ) Zone 2. In Class I, Zone 2 locations, seals shall be located as conduit seal. follows. b. Conduit seals shall be installed within 18 in. (457 mm) from the enclosure. Only explosionproof unions, couplings, reducers, elbows, capped elbows, and conduit bodies similar to L, T, and Cross types that are not larger than the trade size of the conduit shall be permitted between the sealing fitting and the explosionproof enclosure. c. Where two or more explosionproof enclosures for which conduit seals are required under (b)(2) are connected by nipples or by runs of conduit not more than 36 in. (914 mm) long, a single conduit seal in each such nipple connection or run of conduit shall be considered sufficient if located not more than 18 in. (457 mm) from either enclosure. (3) In each conduit entry into a pressurized enclosure where the conduit is not pressurized as part of the protection system. Conduit seals shall be installed within 18 in. (457 mm) from the pressurized enclosure. FPN No. 1: Installing the seal as close as possible to the enclosure will reduce problems with purging the dead airspace in the pressurized cond uit. FPN No. 2: For further information, see Standard for Purged and Pressurized Enclosures for Electrical Equipment, NFPA 496-1998. (4) In each conduit run leaving a Class I, Zone 1 location. The sealing fitting shall be permitted on either side of the boundary of such location within 10 ft (3.05 m) of the boundary, and shall be designed and installed so to minimize the amount of gas or vapor within the Zone 1 portion of the conduit from being communicated to the conduit beyond the seal. Except for liste d explosionproof reducers at the conduit seal, there shall be no union, coupling, box, or fitting between the conduit seal and the point at which the conduit leaves the Zone 1 location. Exception: Metal conduit containing no unions, couplings, boxes, or ttings that passes completely through a Class I, fi Zone 1 location with no fittings less than 12 in. (305 mm) beyond each boundary shall not require a conduit seal if the termination points of the unbroken conduit are in unclassified locations. (5) Conduits containing cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall be sealed in the Zone 1 location after removing the jacket and any other coverings so that the sealing compound will surround each individual insulated conductor and the outer jacket. Exception: Multiconductor cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall be permitted to be considered as a single conductor byaling the cable in the conduit within 18 se in. (457 mm) of the enclosure and the cable end within the enclosure by an approved means to minimize the entrance of gases or vapors and prevent the propagation of flame into the cable core, or by other approved me For shielded cables thods. (1) Conduit seals shall be located as follows. (a) For connections to enclosures that are required to be flameproof or explosionproof, a conduit seal shall be provided in accordance with (b)(1) and (b)(2). All portions of the conduit run or nipple between the seal and such enclosure shall comply with Section 505-16(b). ( 2) In each conduit run passing from a Class I, Zone 2 location into an unclassified location. The sealing fitting shall be permitted on either side of the boundary of such location within 10 ft (3.05 m) of the boundary, and shall be designed and installed so to minimize the amount of gas or vapor within the Zone 2 portion of the conduit from being communicated to the conduit beyond the seal. Rigid metal conduit or threaded steel intermediate metal conduit shall be used between the se aling fitting and the point at which the conduit leaves the Zone 2 location, and a threaded connection shall be used at the sealing fitting. Except for listed explosionproof reducers at the conduit seal, there shall be no union, coupling, box, or fitting between the conduit seal and the point at which the conduit leaves the Zone 2 location. Exception No. 1: Metal conduit containing no unions, couplings, boxes or fittings that passes completely through a Class I, Zone 2 location with no fittings less than (305 12 in. mm) beyond each boundary shall not be required to be sealed if the termination points of the unbroken conduit are in unclassified locations. Exception No. 2: Conduit systems terminating at an unclassified location where a wiring method transit made ion is to cable tray, cablebus, ventilated busway, Type MI cable, or open wiring shall not be required to be sealed where passing from the Class I, Zone 2 location into the unclassified location. The unclassified location shall be outdoors or, if the conduit system is all in one room, it shall be permitted to be indoors. The conduits shall not terminate at an enclosure containing an ignition source in normal operation. Exception No. 3: Conduit systems passing from an enclosure or room that is unclass ified as a result of pressurization into a Class I, Zone 2 location shall not require a seal at the boundary. FPN: For further information, refer to Standard for Purged and Pressurized Enclosures for Electrical Equipment, NFPA 496-1998. Exception No. 4: Segments of aboveground conduit systems shall not be required to be sealed where passing from a Class I, Zone 2 location into an unclassified location if the following conditions are met: 1. No part of the conduit system segment passes through a Class I, Zone 0 or Class I, Zone 1 location where the conduit

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contains unions, couplings, boxes, or fittings within 12 in. (305 mm) of the Class I, Zone 0 or Class I, Zone 1 location; and 2. The conduit system segment is located entirely in outdoor locations; a nd 3. The conduit system segment is not directly connected to canned pumps, process or service connections for flow, pressure, or analysis measurement, etc., that depend on a single compression seal, diaphragm, or tube to prevent flammable or combustible from entering the conduit fluids system; and

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(d) Cables that do not have gas/ vaportight continuous sheath shall be sealed at the boundary of the Zone 2 and unclassified location in such a manner as to minimize the passage of gases or vapors into an unclassified location. FPN: The cable sheath may be either metal or a nonmetallic material. (d) Class I, Zones 0, 1 and 2 . Where required, seals in Class I, Zones 0, 1 and 2 locations shall comply with the following.

(1) Fittings. Enclosures for connections or equipment shall be provided with an integral means for sealing, or sealing fittings for 4. The conduit system segment contains only threaded metal Class I locatio ns shall be used. Sealing fittings shall be accessible. conduit, unions, couplings, conduit bodies, and fittings in the Sealing fittings shall be listed for use with one or more specific unclassified location; and compounds and shall be accessible. 5. The conduit system segment is sealed at its entry h eac to enclosure or fitting housing terminals, splices, or taps in Class I, Zone 2 locations. (3) Cable seals shall be located as follows. (a) Cables entering enclosures required to be flameproof or explosionproof shall be sealed at the point of entrance. The seal shall comply with (d). Multiconductor cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall be sealed in the Zone 2 location after removing the jacket and any other coverings so that the sealing compound will surround each individual insulated conductor in such a manner as to minimize the passage of gases and vapors. Multiconductor cables in conduit shall be sealed as described in (b)(4). Exception No. 1: Cables passing from an enclosure or room that is unclassified as a result of Type Z pressurization into a Class I, Zone 2 location shall not require a seal at the boundary. (3) Thickness of Compounds. In a completed seal, the minimum thickness of the sealing compound shall not be less than t he trade size of the sealing fitting and, in no case, less than 5/8 in. (16 mm). Exception: Listed cable sealing fittings shall not be required to have a minimum thickness equal to the trade size of the fitting. (4) Splices and Taps. Splices and taps shal l not be made in fittings intended only for sealing with compound, nor shall other fittings in which splices or taps are made be filled with compound. (5) Conductor Fill. The cross-sectional area of the conductors permitted in a seal shall not exceed 25 p ercent of the crosssectional area of a rigid metal conduit of the same trade size unless it is specifically listed for a higher percentage of fill. (2) Compound. The compound shall provide a seal against passage of gas or vapors through the seal fitting, shall not be affected by the surrounding atmosphere or liquids, and shall not have a melting point of less than 93ºC (200ºF).

(e) Drainage. Exception No. 2: Shielded cables and twisted pair cables shall not require the removal of the shielding material o r separation (1) Control Equipment. Where there is a probability that liquid of the twisted pairs provided the termination is by an approved or other condensed vapor may be trapped within enclosures for means to minimize the entrance of gases or vapors and preventcontrol equipment or at any point in the raceway system, approved propagation of flame into the cable core. means shall be provided to prevent accumulation or to permit periodic draining of such liquid or condensed vapor. (b) Cables with a gas/vaportight continuous sheath and that will not transmit gases or vapors through the cable (2) Motors and Generators. Where the authority having core in excess of the quantity permitted for seal fittings jurisdiction judges that there is a probability that liquid or shall not be required to be sealed except as required in condensed vapor may accumulate within motors or generators, (2)(a). The minimum length of such cable run shall not joints and conduit systems shall be arranged to minimize entrance be less than that length that limits gas or vapor flow of liquid. If means to prevent accumulation or to permit periodic through the cable core to the rate permitted for seal draining are judged necessary, such means shall be provided at the fittings [0.007 ft3/hour (198 cm3/hour) of air at a time of manufacture and shall be considered an integral part of the pressure of 6 in. of water (1493 pascals)]. machine. FPN No. 1: See Outlet Boxes and Fittings for Use in Hazardous (Classified) Locations, ANSI/UL 886-1994. FPN No. 2: The cable core does not include the interstices of the conductor strands. (c) Cables with a gas/ vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall not be required to be sealed except as required in (2)(a), unless the cable is attached to process equipment or devices that may cause a pressure in excess of 6 in. of water (1493 pascals ) to be exerted at a cable end, in which case a seal, barrier, or other means shall be provided to prevent migr ation of flammables into an unclassified area. Exception: Cables with an unbroken vaportight gas/ continuous sheath shall be permitted to pass through a Class I, Zone 2 location without seals. (3) Canned Pumps, Process or Service Connections, Etc. For canned pumps, process or servic e connections for flow, pressure, or analysis measurement, etc., that depend upon a single compression seal, diaphragm, or tube to prevent flammable or combustible fluids from entering the electrical conduit system, an additional approved seal, barrier, or other means shall be provided to prevent the flammable or combustible fluid from entering the conduit system beyond the additional devices or means, if the primary seal fails. The additional approved seal or barrier and the interconnecting enclosure shall meet the temperature and pressure conditions to which they will be subjected upon failure of the primary seal, unless other approved means are provided to accomplish the purpose above. Drains, vents, or other devices shall be provided so that primary seal leakage will be obvious. (14-368)

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505-17. Flexible Cords, Class I, Zones 1 and 2 . A flexible cord shall be permitted for connection between portable lighting equipment or other portable utilization equipment and the fixed portion of their supply circui t. Flexible cord shall also be permitted for that portion of the circuit where the fixed wiring methods of Section 505-15(b) cannot provide the necessary degree of movement for fixed and mobile electrical utilization equipment, in an industrial establishment where conditions of maintenance and engineering supervision ensure that only qualified persons will install and service the installation, and the flexible cord is protected by location or by a suitable guard from damage. The length of the flexible cor d shall be continuous. Where flexible cords are used, the cords shall be as follows: 1. Of a type listed approved for extra-hard usage; 2. Contain, in addition to the conductors of the circuit, a grounding conductor complying with Section 400-23; 3. Connected to terminals or to supply conductors in an approved manner; 4. Be supported by clamps or by other suitable means in such a manner that there will be no tension no the terminal connections; and 5. Be provided with suitable seals where th e flexible cord enters boxes, fittings, or enclosures that are required to be explosionproof or flameproof. Exception: As provided in 505-15(c). Electric submersible pumps with means for removal without entering the wet-pit shall be considered portable utilization equipment. The extension of the flexible cord within a suitable raceway between the wet-pit and the power source shall be permitted. Electric mixers intended for travel into and out of open-type mixing tanks or vats shall be considered portable utilization equipment. FPN: See Section 505-18 for flexible cords exposed to liquids having a deleterious effect on the conductor insulation. [14-173] 505-19. Conductors and Conductor Insulation. 1) For Type of Protection "e", field wiring conductors shall be copper. (14-365) 2) Where condensed vapors or liquids may collect on, or come in contact with, the insulation on conductors, such insulation shall be of a type approved for use under such conditions; or the insulation shall be protected by a sheat h of lead or by other approved means. (14-181) 505-19. Live Parts. T here shall be no exposed live parts.(14-188) 505-20. Equipment (a) Zone 0. In Class I, Zone 0 locations, only equipment specifically listed and marked as suitable for the location shall be permitted. Exception: Intrinsically safe equipment listed for use in Class I, Division 1 locations for the same gas, or as permitted by Section 505-7(d), and with a suitable temperature classification rating shall be permitted. [correlation Art500 temperature] (b) Zone 1. In Class I, Zone 1 locations, only equipment specifically identified listed and marked as suitable for the location shall be permitted. [correlation with Cook identifed & Art 500 , CP140?, CP140x ,] Exception: Equipment approved for use in Class I, Division 1 or listed for use in Class I, Zone 0 locations for the same gas, or as permitted by Section 505-7(d) and with a suitable temperature classification rating shall be permitted. (c) Zone 2. In Class I, Zone 2 locations, only equipment specifically identified listed and marked as suitable for the location shall be permitted. [see above] Exception No. 1: Equipment identified listed for use in Class I, Zone 0 or Zone 1 locations for the same gas, or as permitted by Section 505-9(a)(2)505-7(d), and with a suitable temperature classificationrating, shall be permitted.

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Exception No. 2: Equipment identified approved for use in Class I, Division 1 or Division 2 locations for the same gas, or as permitted by Section 505-9(a)(2) 505-7(d), and with a suitable temperature classification rating shall be permitted. Exception No. 3: In Class I, Zone 2 locations, the installation of open or nonexplosionproof or nonflameproof enclosed motors, such as squirrel-cage induction motors without brushes, switching mechanisms, or similar arc-producing devices that are not identified for use in a Class I, Zone 2 location shall be permitted. FPN No. 1: It is important to consider the temperature of internal and external surfaces that may be exposed to the flammable atmosphere. FPN No. 2: It is important to consider the risk of ignition due to currents arcing across discontinuities and overheating of parts in multisection enclosures of large motors and generators. Such motors and generators may need equipotential bonding jumpers across joints in the enclosure and from enclosure to ground. Where the presence of ignitible gases or vapors is suspected, clean air purging may be needed immediately prior to and during start-up periods. (d) Manufacturer's Instructions. Electrical equipment installed in hazardous (classified) locations shall be installed in accordance with the instructions (if any) provided by the manufacturer. 505-21. Multiwire Branch Circuits . In a Class I, Zone 1 location, a multiwire branch circuit shall not be permitted. Exception: Where the disconnect device(s) for the circuit opens all ungrounded conductors of the multiwire circuit simultaneously. [14-198] 505-22. .[505-21]Increased Safety "e" Motors and Generators. In Class I, Zone 1 locations, Increased Safety "e" motors and generators of all voltage ratings shall be listed for Class I, Zone 1 locations, and shall comply with the following. 1. Motors shall be marked with the current ratio, IA/IN, and time, tE; 2. Motors shall have controllers marked with the model or identification number, output rating (horsepower or kilowatt), fullload amperes, starting current ratio (IA/IN), and time (tE) of the motors that they are intended to protect; the controller marking shall also include the specific overload protection type (and setting, if applicable) that is listed with the motor or generator; 3. Connections shall be made with the specific terminals listed with the motor or generator; 4. Terminal housings shall be permitted to be of substantial, nonmetallic, nonburning material provided an internal grounding means between the motor frame and the equipment grounding connection is incorporated within the housing; 5. The provisions of Part C of Article 430 shall apply regardless of the voltage rating of the motor; 6. The motors shall be protected against overload by a separate overload device that is responsive to motor current. This device shall be selected to trip or shall be rated in accordance with the listing of the motor and its overload protection; 7. Sections 430-34 and 430-44 shall not apply to such motors; and 8. The motor overload protection shall not be shunted or cut out during the starting period. 505-25. Grounding and Bonding. Grounding and bonding shall comply with Article 250 and the following additional requirements. (a) Bonding. The locknut -bushing and double-locknut types of contacts shall not be depended on for bonding purposes, but bonding jumpers with proper fittings or other approved means of bonding shall be used. Such means of bonding shall apply to all intervening raceways, fittings, boxes, enclosures, etc., between Class I locations and the point of grounding for service equipment or point of grounding of a separately derived system. Exception: The specific bondi ng means shall only be required to the nearest point where the grounded circuit conductor and the grounding electrode are connected together on the line side of the building or structure disconnecting

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means as specified in Sections 250-32(a), (b), and (c), provided the branch-circuit overcurrent protection is located on the load side of the disconnecting means. FPN: See Section 250-100 for additional bonding requirements in hazardous (classified) locations. (b) Types of Equipment Grounding Conductors. Where flexible metal conduit or liquidtight flexible metal conduit is used as permitted in Section 505-15(c) and is to be relied on to complete a sole equipment grounding path, it shall be installed with internal or external bonding jumpers in parallel with each conduit and complying with Section 250-102. Exception: In Class I, Zone 2 locations, the bonding jumper shall be permitted to be deleted where all the following conditions are met. a. Listed liquidtight flexible metal conduit 6 ft (1.83 m) or less in length, with fittings listed for grounding, is used. b. Overcurrent protection in the circuit is limited to 10 amperes or less. c. The load is not a power utilization load. ___________________ (Log #2136) 14- 320 - (505): Accept in Principle SUBMITTER: Kari Barrett, Chemical Manufacturers Assn. RECOMMENDATION: Reorganize Article 505 as indicated below per NEC CMA Proposal 14-1b. With the exception of minor titling changes and a rearrangement of sentences as indicated within one section, this proposal contains no new words, concepts or requirements. Revise Article 505 as follows: 1) Rename 505-3 as "General"; relocate entire section 505-10 (c) as new item (a) titled "Documentation of Industrial Occupancies." Also relocate section 505-5 Reference Standards to new item (b). With change: 505-3 General. (a) Documentation for Industrial Occupancies. 505-10 (c) Documentation for Industrial Occupancies. All areas in industrial occupancies designated as hazardous (classified) locations shall be properly documented. This documentation shall be available to those authorized to design, install, inspect, maintain, or operate electrical equipment at the location. FPN: For examples of area classification drawings, see Electrical Apparatus for Explosive Gas Atmospheres, Classification of Hazardous Areas, IEC 79-10-1995; Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Zone 0, Zone 1, or Zone 2, API RP 505-1997; Electrical Apparatus for Explosive Gas Atmospheres, Classifications of Hazardous (Classified) Locations, ISA S12.24.01-1997; Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Division I or Division 2, API RP 5001997, Model Code of Safe Practice in the Petroleum Industry, Part 15: Area Classification Code for Petroleum Installations, IP 15, The Institute of Petroleum, London. (b) Reference Standards. 505-5. Reference Standards FPN No. 1: It is important that the authority having jurisdiction be familiar with recorded industrial experience as well as with standards of the National Fire Protection Association, the American Petroleum Institute, and the International Society for Measurement and Control (ISA), that may be of use in the classification of various locations, the determination of adequate ventilation, and the protection against static electricity and lightning hazards. FPN No. 2: For further information on the classification of locations, see Electrical Apparatus for Explosive Gas Atmospheres, Classification of Hazardous Areas, IEC 7910-1995; Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Zone 0, Zone 1, or Zone 2, API RP 505-1996; Electrical Apparatus for Explosive Gas Atmospheres, Classifications of Hazardous (Classified) Locations, ISA S12.24.01-1997; and Model Code of Safe Practice in the Petroleum Industry, Part 15: Area Classification Code for Petroleum Installations, IP 15, The Institute of Petroleum, London.

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FPN No. 3: For further information on protection against static electricity and lightning hazards in hazardous (classified) locations, see Recommended Practice on Static Electricity, NFPA 77-1993; Standard for the Installation of Lightning Protection Systems, NFPA 7801997; and Protection Against Ignitions Arising Out of Static Lightning and Stray Currents, API RP 2003-1991. FPN No. 4: For further information on ventilation, see Flammable and Combustible Liquids Code, NFPA 301996, and Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Division 1 or Division 2, API RP 500-1997, Section 6.3. FPN No. 5: For further information on electrical systems for hazardous (classified) locations on offshore oil and gas producing platforms, see Design and Installation of Electrical Systems for Offshore Production Platforms, ANSI/API RP 14F-1991. FPN No. 6: For further information on the installation of electrical equipment in hazardous (classified) locations in general, see Electrical Apparatus for Explosive Gas Atmospheres -- Part 14: Electrical Installations in Explosive Gas Atmospheres (Other than Mines), IEC 7914-1996, and Electrical Apparatus for Explosive Gas Atmospheres -- Part 16: Artificial Ventilation for the Protection of Analyzer(s) Houses, IEC 79-16-1990.

2) Rename and number existing 505-3 as 505-4 and provide a new title "Classification of Locations. Relocate sections 505-9 (a) (b) (c) under this section and renumber accordingly. With change: 505-4 Classifications of Locations. 505-3. Location and General Requirements. (a) Classification of Locations. Locations shall be classified depending on the properties of the flammable vapors, liquids, or gases that may be present and the likelihood that a flammable or combustible concentration or quantity is present. Where pyrophoric materials are the only materials used or handled, these locations shall not be classified. Each room, section, or area shall be considered individually in determining its classification. FPN No. 1: See Section 505-6 for restrictions on area classification. FPN No. 2: Through the exercise of ingenuity in the layout of electrical installations for hazardous (classified) locations, it is frequently possible to locate much of the equipment in less hazardous or in nonhazardous locations and, thus, to reduce the amount of special equipment required. (b) Class I Zone Locations. Class I Zone locations are those in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitible mixtures. Class I Zone locations shall include those specified in (1), (2) and (3). 505-9. Zone Classification The classification into zones shall be in accordance with the following. (1) Class I, Zone 0. A Class I, Zone 0 location is a location (a) In which ignitible concentrations of flammable gases or vapors are present continuously, or (b) In which ignitible concentrations of flammable gases or vapors are present for long periods of time. FPN No. 1: As a guide in determining when flammable gases or vapors are present continuously or for long periods of time, refer to Recommended Practice for Classification of Locations for Electrical Installations of Petroleum Facilities Classified as Class I, Zone 0, Zone 1 or Zone 2, API RP 505-1996; Electrical Apparatus for Explosive Gas Atmospheres, Classifications of Hazardous Areas, IEC 79-10-1995; and Area Classification Code for Petroleum Installations, Model Code, Part 15, Institute of Petroleum; and Electrical Apparatus for Explosive Gas Atmospheres, Classifications of Hazardous (Classified) Locations, ISA S12.24.01-1997. FPN No. 2: This classification includes locations inside vented tanks or vessels that contain volatile flammable liquids; inside inadequately vented spraying or coating enclosures, where volatile flammable solvents are used; between the inner and outer roof sections of a floating roof tank containing volatile flammable liquids; inside

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open vessels, tanks and pits containing volatile flammable liquids; the interior of an exhaust duct that is used to vent ignitible concentrations of gases or vapors; and inside inadequately ventilated enclosures that contain normally venting instruments utilizing or analyzing flammable fluids and venting to the inside of the enclosures. FPN No. 3: It is not good practice to install electrical equipment in Zone 0 locations except when the equipment is essential to the process or when other locations are not feasible. [See Section 505-3(a) FPN No. 2.] If it is necessary to install electrical systems in a Zone 0 location, it is good practice to install intrinsically safe systems as described by Article 504. (2) Class I, Zone 1. A Class I, Zone 1 location is a location (a) In which ignitible concentrations of flammable gases or vapors are likely to exist under normal operating conditions; or (b) In which ignitible concentrations of flammable gases or vapors may exist frequently because of repair or maintenance operations or because of leakage; or (c) In which equipment is operated or processes are carried on, of such a nature that equipment breakdown or faulty operations could result in the release of ignitible concentrations of flammable gases or vapors and also cause simultaneous failure of electrical equipment in a mode to cause the electrical equipment to become a source of ignition; or (d) That is adjacent to a Class I, Zone 0 location from which ignitible concentrations of vapors could be communicated, unless communication is prevented by adequate positive pressure ventilation from a source of clean air and effective safeguards against ventilation failure are provided. FPN No. 1: Normal operations is considered the situation when plant equipment is operating within its design parameters. Minor releases of flammable material may be part of normal operations. Minor releases include the releases from mechanical packings on pumps. Failures that involve repair or shutdown (such as the breakdown of pump seats and flange gaskets, and spillage caused by accidents) are not considered normal operation. FPN No. 2: This classification usually includes locations where volatile flammable liquids or liquefied flammable gases are transferred from one container to another. In areas in the vicinity of spraying and painting operations where flammable solvents are used; adequately ventilated drying rooms or compartments for evaporation of flammable solvents; adequately ventilated locations containing fat and oil extraction equipment using volatile flammable solvents; portions of cleaning and dyeing plants where volatile flammable liquids are used; adequately ventilated gas generator rooms and other portions of gas manufacturing plants where flammable gas may escape; inadequately ventilated pump rooms for flammable gas or for volatile flammable liquids; the interiors of refrigerators and freezers in which volatile flammable materials are stored in the open, lightly stoppered, or easily ruptured containers; and other locations where ignitible concentrations of flammable vapors or gases are likely to occur in the course of normal operation, but not classified Zone 0. (3) Class I, Zone 2. A Class I, Zone 2 location is a location (a) In which ignitible concentrations of flammable gases or vapors are not likely to occur in normal operation and if they do occur will exist only for a short period; or (b) In which volatile flammable liquids, flammable gases, or flammable vapors are handled, processed, or used, but in which the liquids, gases, or vapors normally are confined within closed containers of closed systems from which they can escape, only as a result of accidental rupture or breakdown of the containers or system, or as a result of the abnormal operation of the equipment with which the liquids or gases are handled, processed, or used; or (c) In which ignitible concentrations of flammable gases or vapors normally are prevented by positive mechanical ventilation, but which may become hazardous as a result of failure or abnormal operation of the ventilation equipment; or (d) That is adjacent to a Class I, Zone 1 location, from which ignitible concentrations of flammable gases or vapors could be communicated, unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air, and effective safeguards against ventilation failure are provided.

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FPN: The Zone 2 classification usually includes locations where volatile flammable liquids or flammable gases or vapors are used, but which would become hazardous only in case of an accident or of some unusual operating condition.

3) Make section 505-5 "Material Groups" and relocate section 507 (a) (b) and (c) under this section, renumbering as shown. With change: 505-5 Material Groups. 505-7. Grouping and Classification. For purposes of testing, approval, and area classification, various air mixtures (not oxygen enriched) shall be grouped as required in (a), (b), and (c). FPN: Group I is intended for use in describing atmospheres that contain firedamp (a mixture of gases, composed mostly of methane, found underground, usually in mines). This Code does not apply to installations underground in mines. See Section 90-2(b). Group II shall be subdivided into IIC, IIB, and IIA, as noted in (a), (b), and (c), according to the nature of the gas or vapor, for protection techniques "d," "ia," "ib," "[ia]," and "[ib]," and, where applicable, "n" and "o." FPN No. 1: The gas and vapor subdivision as described above is based on the maximum experimental safe gap (MESG), minimum igniting current (MIC), or both. Test equipment for determining the MESG is described in Construction and Verification Tests of Flameproof Enclosures of Electrical Apparatus, IEC 79-1A-1975, Amendment No. 1 (1993) and UL Technical Report No. 58 (1993). The test equipment for determining MIC is described in Spark-Test Apparatus for Intrinsically-Safe Circuits, IEC 79-3-1990. The classification of gases or vapors according to their maximum experimental safe gaps and minimum igniting currents is described in Classification of Mixtures of Gases or Vapours with Air According to Their Maximum Experimental Safe Gaps and Minimum Igniting Currents, IEC 79-12-1978. FPN No. 2: Verification of electrical equipment utilizing protection techniques "e," "m," "p," and "q," due to design technique, does not require tests involving MESG or MIC. Therefore, Group II is not required to be subdivided for these protection techniques. FPN No. 3: It is necessary that the meanings of the different equipment markings and Group II classifications be carefully observed to avoid confusion with Class I, Divisions 1 and 2, Groups A, B, C, and D. (a) Class I Zone Group Classifications. Class I Zone groups shall be as follows: (1) Group IIC. Atmospheres containing acetylene, hydrogen, or flammable gas, flammable liquid-produced vapor, or combustible liquid-produced vapor mixed with air that may burn or explode, having either a maximum experimental safe gap (MESG) value less than or equal to 0.50 mm or minimum igniting current ratio (MIC ratio) less than or equal to 0.45. FPN: Group IIC is equivalent to a combination of Class I, Group A, and Class I, Group B, as described in Sections 500-5(a)(1) and (a)(2). (2) Group IIB. Atmospheres containing acetaldehyde, ethylene, or flammable gas, flammable liquid-produced vapor, or combustible liquid-produced vapor mixed with air that may burn or explode, having either maximum experimental safe gap (MESG) values greater than 0.50 mm and less than or equal to 0.90 mm or minimum igniting current ratio (MIC ratio) greater than 0.45 and less than or equal to 0.80. FPN: Group IIB is equivalent to Class I, Group C, as described in Section 500-5(a)(3). (3) Group IIA. Atmospheres containing acetone, ammonia, ethyl alcohol, gasoline, methane, propane, or flammable gas, flammable liquid-produced vapor, or combustible liquid-produced vapor mixed with air that may burn or explode, having either a maximum experiment safe gap (MESG) value greater than 0.90 mm or minimum igniting current ratio (MIC ratio) greater than 0.80. FPN: Group IIA is equivalent to Class I, Group D as described in Section 500-5(a)(4).

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4) Retain 505-6 as is. 5) Make 505-7 "Protection Techniques" and relocate all of 505-4 (a) - (h) under this section. With change: 505- 7 Protection Techniques. 505-4. Protection Techniques. The following shall be acceptable protection techniques for electrical and electronic equipment in hazardous (classified) locations. FPN: For additional information, see Electrical Apparatus for Use in Class I, Zone 0, 1 Hazardous (Classified) Locations General Requirements, ISA S12.0.01-1997; Electrical Equipment for Use in Class I, Zone 0, 1, and 2 Hazardous (Classified) Locations, ANSI/UL 2279, 1997; and Electrical Apparatus for Explosive Gas Atmospheres - Part 0: General Requirements, IEC 79-0-1983, Amendment No. 1 (1987), and Amendment No. 2 (1991). (a) Flameproof "d." This protection technique shall be permitted for equipment in those Class I, Zone 1 locations for which it is approved. FPN No. 1: Flameproof is a type of protection of electrical equipment in which the enclosure will withstand an internal explosion of a flammable mixture that has penetrated into the interior, without suffering damage and without causing ignition, through any joints or structural openings in the enclosure, of an external explosive atmosphere consisting of one or more of the gases or vapors for which it is designed. FPN No. 2: For further information, see Electrical Apparatus for Use In Class I, Zone 1 and 2 Hazardous (Classified) Locations, Type of Protection -- Flameproof "d," ISA S12.22.01-1996; Electrical Apparatus for Explosive Gas Atmospheres, Part 1 -- Construction and Verification Test of Flameproof Enclosures of Electrical Apparatus, IEC 79-1-1990 and Amendment No. 1 (1993). (b) Purged and Pressurized. This protection technique shall be permitted for equipment in those Class I, Zone 1 or Zone 2 locations for which it is approved. FPN No. 1: In some cases, hazards may be reduced or hazardous (classified) locations limited or eliminated by adequate positive-pressure ventilation from a source of clean air in conjunction with effective safeguards against ventilation failure. FPN No. 2: For further information, see Standard for Purged and Pressurized Enclosures for Electrical Equipment, NFPA 496-1998. FPN No. 3: Pressurized "p" is a type of protection of electrical equipment that uses the technique of guarding against the ingress of the external atmosphere, which may be explosive, into an enclosure by maintaining a protective gas therein at a pressure above that of the external atmosphere. For further information, see Electrical Apparatus for Explosive Gas Atmospheres Part 2: Electrical Apparatus, Type of Protection "p," IEC 79-2-1983; and Electrical Apparatus for Explosive Gas Atmospheres - Part 13: Construction and Use of Rooms or Buildings Protected by Pressurization, IEC 79-13-1982. (c) Intrinsic Safety. This protection technique shall be permitted for equipment in those Class I, Zone 0 or Zone 1 locations for which it is approved. FPN No. 1: Intrinsic safety is designated type of protection "ia" by IEC 79-11 for use in Zone 0 locations. Intrinsic safety is designated type of protection "ib" by IEC 79-11 for use in Zone 1 locations. FPN No. 2: For further information, see Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I, II, and III, Hazardous Locations, ANSI/UL 913-1997; Electrical Apparatus for Explosive Gas Atmospheres -- Part 11: Intrinsic Safety "i," IEC 79-11-1991; and Electrical Apparatus for Explosive Gas Atmospheres -- Part 3: Spark-test Apparatus for Intrinsically-safe Circuits, IEC 79-3-1990. FPN No. 3: Intrinsically safe associated apparatus, designated by [ia] or [ib], is connected to intrinsically safe equipment ("ia" or "ib" respectively), but is located

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outside the hazardous (classified) location unless also protected by another type of protection (such as flameproof).

(d) Type of Protection "n." This protection technique shall be permitted for equipment in those Class I, Zone 2 locations for which it is approved. Type of protection "n" is further subdivided into nA, nC, and nR. FPN No. 1: See Table 505-10(b) 1 for the descriptions of subdivisions for type of protection "n." FPN No. 2: Type "n" protection is a type of protection applied to electrical equipment such that, in normal operation, the electrical equipment is not capable of igniting a surrounding explosive gas atmosphere and a fault capable of causing ignition is not likely to occur. FPN No. 3: For further information, see Electrical Apparatus for Explosive Gas Atmospheres, Part 15 -- Electrical Apparatus with Type of Protection "n," IEC 7915-1987. (e) Oil Immersion "o." This protection technique shall be permitted for equipment in those Class I, Zone 1 locations for which it is approved. FPN No. 1: Oil immersion is a type of protection in which the electrical equipment or parts of the electrical equipment are immersed in a protective liquid in such a way that an explosive atmosphere that may be above the liquid or outside the enclosure cannot be ignited. FPN No. 2: For further information, see Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations, Type of Protection -- OilImmersion "o," ISA S12.26.01 -- 1996; and Electrical Apparatus for Explosive Gas Atmospheres, Part 6 -- OilImmersion "o," IEC 79-6-1995. (f) Increased Safety "e." This protection technique shall be permitted for equipment in those Class I, Zone 1 locations for which it is approved. FPN No. 1: Increased safety is a type of protection applied to electrical equipment that does not produce arcs or sparks in normal service and under specified abnormal conditions, in which additional measures are applied so as to give increased security against the possibility of excessive temperatures and of the occurrence of arcs and sparks. FPN No. 2: For further information, see Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations, Type of Protection -- Increased Safety "e," ISA S12.16.01-1996; and Electrical Apparatus for Explosive Gas Atmospheres -- Part 7: Increased Safety "e," IEC 79-7-1990, Amendment No. 1 (1991), and Amendment No. 2 (1993). (g) Encapsulation "m." This protection technique shall be permitted for equipment in those Class I, Zone 1 locations for which it is approved. FPN No. 1: Encapsulation is a type of protection in which the parts that could ignite an explosive atmosphere by either sparking or heating are enclosed in a compound in such a way that this explosive atmosphere cannot be ignited. FPN No. 2: For further information, see Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations Type of Protection -- Encapsulation "m," ISA S12.23.01-1996, and Electrical Apparatus for Explosive Gas Atmospheres -- Part 18: Encapsulation "m," IEC 79-18-1992. (h) Powder Filling "q." This protection technique shall be permitted for equipment in those Class I, Zone 1 locations for which it is approved. FPN No. 1: Powder filling is a type of protection in which the parts capable of igniting an explosive atmosphere are fixed in position and completely surrounded by filling material (glass or quartz powder) to prevent the ignition of an external explosive atmosphere. FPN No. 2: For further information, see Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations Type of Protection -- Powder Filling "q," ISA S12.25.01-1996, and Electrical Apparatus for Explosive Gas Atmospheres -- Part 5: Powder Filling, Type of Protection "q," IEC 79-5-1967.

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6) Title section 505-8 Equipment, relocate 505-10 (a) as item (a) (1), relocate 505-7 (d) as (a) (2); create new section (b) titled "Marking" and move under this section 505-10 (b) (1) & (2); create new section (c) titled "Class I Temperature" and move 505-8 and 505-10 (b) (3) under this new section; create new section (d) titled "Threading" and relocate 505-3 (b) under this section. Renumber figures and tables accordingly. With change: 505-8 Equipment. (a) Listing. (1) Equipment that is listed for a Zone 0 location shall be permitted in a Zone 1 or Zone 2 location of the same gas or vapor. Equipment that is listed for a Zone 1 location shall be permitted in a Zone 2 location of the same gas or vapor. (2) (d) Other. Equipment shall be permitted to be listed for a specific gas or vapor, specific mixtures of gases or vapors, or any specific combination of gases or vapors. FPN: One common example is equipment marked for "IIB + H2." (b) Marking. (b) Marking. Equipment shall be marked in accordance with (1) or (2). (1) Division Equipment. Equipment approved for Class I, Division 1 or Class I, Division 2 shall, in addition to being marked in accordance with Section 500-7(b), be permitted to be marked with the following: a. Class I, Zone 1 or Class I, Zone 2 (as applicable), and b. Applicable gas classification group(s) in accordance with Table 505-8(b)(2), and c. Temperature classification in accordance with Section 505-8(c)

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Table 505-8(b)(1). Types of Protection Designation Designation Technique Zone* d Flameproof enclosure 1 e Increased safety 1 ia Intrinsic safety 0 ib Intrinsic safety 1 [ia] Intrinsically safe Nonhazardous associated apparatus [ib] Intrinsically safe Nonhazardous associated apparatus m Encapsulation 1 nA Nonsparking equipment 2 nC Sparking equipment in 2 which the contacts are suitably protected other than by restricted breathing enclosure nR Restricted breathing 2 enclosure o Oil immersion 1 p Purged and pressurized 1 or 2 q Powder filled 1 * Does not address use where a combination of techniques is used. Table 505-8(b)(2). Gas Classification Groups Gas Group Comment IIC See Section 505-5(a) IIB See Section 505-5(b) IIA See Section 505-5(c) (c) Class I Temperature.

505-8. Class I Temperature. (2) Zone Equipment. Equipment meeting one or more of the The temperature marking specified in Section 505-10(b) shall not protection techniques described in Section 505-4 shall be marked exceed the ignition temperature of the specific gas or vapor to be with the following in the order shown: encountered. a. Class FPN: For information regarding ignition temperatures of b. Zone gases and vapors, see Recommended Practice for the c. Symbol "AEx" Classification of Flammable Liquids, Gases, or Vapors d. Protection technique(s) in accordance with Table 505-10(b)(2) and of Hazardous (Classified) Locations for Electrical e. Applicable gas classification group(s) in accordance with Table Installations in Chemical Process Areas, NFPA 497-1997; 505-10(b)(2) Guide to Fire Hazard Properties of Flammable Liquids, f. Temperature classification in accordance with Section 505Gases, and Volatile Solids, NFPA 325-1994; and Electrical 10(b)(3) Apparatus for Explosive Gas Atmospheres, Data for Exception: Intrinsically safe associated apparatus shall be required to be Flammable Gases and Vapours, Relating to the Use of marked only with (c), (d), and (e). Electrical Apparatus, IEC 79-20-1996. FPN No. 1: An example of such a required marking is "Class I, Zone 0, AEx ia IIC T6." (1) (3) Temperature Classifications. Approved equipment shall be Electrical equipment of types of protection "e," "m," "p," marked to show the operating temperature or temperature range or "q," shall be marked Group II. Electrical equipment referenced to a 40ºC (104ºF) ambient. The temperature range, if of types of protection "d," "ia," "ib," "[ia]," or "[ib]" shall provided, shall be indicated in identification numbers, as shown in be marked Group IIA, or IIB, or IIC, or for a specific Table 505-8(c). gas or vapor. Electrical equipment of types of protection "n" shall be marked Group II unless it contains enclosedTable 505-8(c). Classification of Maximum break devices, nonincendive components, or energySurface Temperature for Group II Electrical limited equipment or circuits, in which case it shall be Equipment marked Group IIA, IIB, or IIC, or a specific gas or vapor. Electrical equipment of other types of protection Temperature Maximum Surface shall be marked Group II unless the type of protection Class Temperature (ºC) utilized by the equipment requires that it shall be marked T1 Û450 Group IIA, IIB, or IIC, or a specific gas or vapor. T2 Û300 T3 FPN No. 2: An explanation of the marking that is Û200 required follows. T4 Û135 T5 Û100 Figure 505-8(b)(1). T6 Û85

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Electrical equipment designed for use in the ambient temperature Classification of Locations for Electrical Installations at range between -20ºC and +40ºC shall require no additional Petroleum Facilities Classified as Class I, Zone 0, Zone 1, temperature marking. or Zone 2, API RP 505-1997; Electrical Apparatus for Electrical equipment that is designed for use in a range of ambient Explosive Gas Atmospheres, Classifications of Hazardous temperatures other than -20ºC and +40ºC is considered to be (Classified) Locations, ISA S12.24.01-1997; special; and the ambient temperature range shall then be marked Recommended Practice for Classification of Locations on the equipment, including either the symbol "Ta" or "Tamb" for Electrical Installations at Petroleum Facilities together with the special range of ambient temperatures. As an Classified as Class I, Division I or Division 2, API RP 500example, such a marking might be "-30ºC Ta + 40ºC." 1997, Model Code of Safe Practice in the Petroleum Electrical equipment suitable for ambient temperatures exceeding Industry, Part 15: Area Classification Code for Petroleum 40ºC (104ºF) shall be marked with both the maximum ambient Installations, IP 15, The Institute of Petroleum, London. temperature and the operating temperature or temperature range at that ambient temperature. (b) Reference Standards. Exception No. 1: Equipment of the nonheat-producing type, such as FPN No. 1: It is important that the authority having conduit fittings, and equipment of the heat-producing type having a jurisdiction be familiar with recorded industrial maximum temperature of not more than 100ºC (212ºF) shall not be experience as well as with standards of the National Fire required to have a marked operating temperature or temperature range. Protection Association, the American Petroleum Exception No. 2: Equipment approved for Class I, Division 1 or Division Institute, and the International Society for Measurement 2 locations as permitted by Sections 505-20(b) and (c) shall be permitted and Control (ISA), that may be of use in the to be marked in accordance with Section 500-5(d) and Table 500-5(d). classification of various locations, the determination of adequate ventilation, and the protection against static (d) Threading. electricity and lightning hazards. (b) Threading. All threaded conduit referred to herein shall be FPN No. 2: For further information on the classification threaded with an NPT standard conduit cutting die that provides _of locations, see Electrical Apparatus for Explosive Gas in. taper per foot. Such conduit shall be made wrenchtight to Atmospheres, Classification of Hazardous Areas, IEC 79prevent sparking when fault current flows through the conduit 10-1995; Classification of Locations for Electrical system, and to ensure the explosionproof or flameproof integrity of Installations at Petroleum Facilities Classified as Class I, the conduit system where applicable. Zone 0, Zone 1, or Zone 2, API RP 505-1996; Electrical Equipment provided with threaded entries for field wiring Apparatus for Explosive Gas Atmospheres, Classifications connections shall be installed in accordance with (1) or (2). of Hazardous (Classified) Locations, ISA S12.24.01-1997; (1) Equipment Provided with Threaded Entries for NPT Threaded and Model Code of Safe Practice in the Petroleum Conduit or Fittings. For equipment provided with threaded entries Industry, Part 15: Area Classification Code for Petroleum for NPT threaded conduit or fittings, listed conduit, conduit Installations, IP 15, The Institute of Petroleum, London. fittings, or cable fittings shall be used. FPN No. 3: For further information on protection against (2) Equipment Provided with Threaded Entries for Metric static electricity and lightning hazards in hazardous Threaded Conduit or Fittings. For equipment with metric threaded (classified) locations, see Recommended Practice on entries, such entries shall be identified as being metric, or listed Static Electricity, NFPA 77-1993; Standard for the adapters to permit connection to conduit or NPT-threaded fittings Installation of Lightning Protection Systems, NFPA 780shall be provided with the equipment. Adapters shall be used for 1997; and Protection Against Ignitions Arising Out of connection to conduit or NPT-threaded fittings. Listed cable Static Lightning and Stray Currents, API RP 2003-1991. fittings that have metric threads shall be permitted to be used. FPN No. 4: For further information on ventilation, see FPN: Threading specifications for metric threaded Flammable and Combustible Liquids Code, NFPA 30entries are located in Metric Screw Threads, ISO 1996, and Recommended Practice for Classification of 965/1:1980, and Metric Screw Threads, ISO 965/3:1980. Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Division 1 or Division 2, 7) Eliminate Section heading 505-10. No changes are made to other API RP 500-1997, Section 6.3. sections that follow 505-10. FPN No. 5: For further information on electrical systems for hazardous (classified) locations on offshore oil and gas producing platforms, see Design and Installation of Article 505 with recommended changes would appear as follows: Electrical Systems for Offshore Production Platforms, ANSI/API RP 14F-1991. ARTICLE 505 -- Class I, Zone 0, 1, and 2 Locations FPN No. 6: For further information on the installation of 505-1. Scope. This article covers the requirements for the zone electrical equipment in hazardous (classified) locations classification system as an alternative to the division classification in general, see Electrical Apparatus for Explosive Gas system covered in Article 500 for electrical and electronic Atmospheres -- Part 14: Electrical Installations in equipment and wiring for all voltages in Class I, Zone 0, Zone 1, Explosive Gas Atmospheres (Other than Mines), IEC 79and Zone 2 hazardous (classified) locations where fire or 14-1996, and Electrical Apparatus for Explosive Gas explosion hazards may exist due to flammable gases, vapors, or Atmospheres -- Part 16: Artificial Ventilation for the liquids. Protection of Analyzer(s) Houses, IEC 79-16-1990. FPN: For the requirements for electrical and electronic equipment and wiring for all voltages in Class I, Division 505-4 Classifications of Locations. 1 or Division 2; Class II, Division 1 or Division 2; and (a) Classification of Locations. Locations shall be classified Class III, Division 1 or Division 2 hazardous (classified) depending on the properties of the flammable vapors, liquids, or locations where fire or explosion hazards may exist due gases that may be present and the likelihood that a flammable or to flammable gases or vapors, flammable liquids, or combustible concentration or quantity is present. Where combustible dusts or fibers, refer to Articles 500 through pyrophoric materials are the only materials used or handled, these 504. locations shall not be classified. Each room, section, or area shall be considered individually in 505-2. Other Articles determining its classification. All other applicable rules contained in this Code shall apply to FPN No. 1: See Section 505-6 for restrictions on area electrical equipment and wiring installed in hazardous (classified) classification. locations. FPN No. 2: Through the exercise of ingenuity in the Exception: As modified by Article 504 and this article. layout of electrical installations for hazardous (classified) locations, it is frequently possible to locate much of the 505-3 General. equipment in less hazardous or in nonhazardous (a) Documentation for Industrial Occupancies. All areas in locations and, thus, to reduce the amount of special industrial occupancies designated as hazardous (classified) equipment required. locations shall be properly documented. This documentation shall be available to those authorized to design, install, inspect, (b) Class I Zone Locations. Class I Zone locations are those in maintain, or operate electrical equipment at the location. which flammable gases or vapors are or may be present in the air FPN: For examples of area classification drawings, see in quantities sufficient to produce explosive or ignitible mixtures. Electrical Apparatus for Explosive Gas Atmospheres, Class I Zone locations shall include those specified in (1), (2) and Classification of Hazardous Areas, IEC 79-10-1995; (3).

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(1) Class I, Zone 0. A Class I, Zone 0 location is a location (a) In which ignitible concentrations of flammable gases or vapors are present continuously, or (b) In which ignitible concentrations of flammable gases or vapors are present for long periods of time. FPN No. 1: As a guide in determining when flammable gases or vapors are present continuously or for long periods of time, refer to Recommended Practice for Classification of Locations for Electrical Installations of Petroleum Facilities Classified as Class I, Zone 0, Zone 1 or Zone 2, API RP 505-1996; Electrical Apparatus for Explosive Gas Atmospheres, Classifications of Hazardous Areas, IEC 79-10-1995; and Area Classification Code for Petroleum Installations, Model Code, Part 15, Institute of Petroleum; and Electrical Apparatus for Explosive Gas Atmospheres, Classifications of Hazardous (Classified) Locations, ISA S12.24.01-1997. FPN No. 2: This classification includes locations inside vented tanks or vessels that contain volatile flammable liquids; inside inadequately vented spraying or coating enclosures, where volatile flammable solvents are used; between the inner and outer roof sections of a floating roof tank containing volatile flammable liquids; inside open vessels, tanks and pits containing volatile flammable liquids; the interior of an exhaust duct that is used to vent ignitible concentrations of gases or vapors; and inside inadequately ventilated enclosures that contain normally venting instruments utilizing or analyzing flammable fluids and venting to the inside of the enclosures. FPN No. 3: It is not good practice to install electrical equipment in Zone 0 locations except when the equipment is essential to the process or when other locations are not feasible. [See Section 505-3(a) FPN No. 2.] If it is necessary to install electrical systems in a Zone 0 location, it is good practice to install intrinsically safe systems as described by Article 504. (2) Class I, Zone 1. A Class I, Zone 1 location is a location (a) In which ignitible concentrations of flammable gases or vapors are likely to exist under normal operating conditions; or (b) In which ignitible concentrations of flammable gases or vapors may exist frequently because of repair or maintenance operations or because of leakage; or (c) In which equipment is operated or processes are carried on, of such a nature that equipment breakdown or faulty operations could result in the release of ignitible concentrations of flammable gases or vapors and also cause simultaneous failure of electrical equipment in a mode to cause the electrical equipment to become a source of ignition; or (d) That is adjacent to a Class I, Zone 0 location from which ignitible concentrations of vapors could be communicated, unless communication is prevented by adequate positive pressure ventilation from a source of clean air and effective safeguards against ventilation failure are provided. FPN No. 1: Normal operations is considered the situation when plant equipment is operating within its design parameters. Minor releases of flammable material may be part of normal operations. Minor releases include the releases from mechanical packings on pumps. Failures that involve repair or shutdown (such as the breakdown of pump seats and flange gaskets, and spillage caused by accidents) are not considered normal operation. FPN No. 2: This classification usually includes locations where volatile flammable liquids or liquefied flammable gases are transferred from one container to another. In areas in the vicinity of spraying and painting operations where flammable solvents are used; adequately ventilated drying rooms or compartments for evaporation of flammable solvents; adequately ventilated locations containing fat and oil extraction equipment using volatile flammable solvents; portions of cleaning and dyeing plants where volatile flammable liquids are used; adequately ventilated gas generator rooms and other portions of gas manufacturing plants where flammable gas may escape; inadequately ventilated pump rooms for flammable gas or for volatile flammable liquids; the interiors of refrigerators and freezers in which volatile flammable materials are stored in the open, lightly stoppered, or easily ruptured containers; and other locations where ignitible concentrations of flammable

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vapors or gases are likely to occur in the course of normal operation, but not classified Zone 0.

(3) Class I, Zone 2. A Class I, Zone 2 location is a location (a) In which ignitible concentrations of flammable gases or vapors are not likely to occur in normal operation and if they do occur will exist only for a short period; or (b) In which volatile flammable liquids, flammable gases, or flammable vapors are handled, processed, or used, but in which the liquids, gases, or vapors normally are confined within closed containers of closed systems from which they can escape, only as a result of accidental rupture or breakdown of the containers or system, or as a result of the abnormal operation of the equipment with which the liquids or gases are handled, processed, or used; or (c) In which ignitible concentrations of flammable gases or vapors normally are prevented by positive mechanical ventilation, but which may become hazardous as a result of failure or abnormal operation of the ventilation equipment; or (d) That is adjacent to a Class I, Zone 1 location, from which ignitible concentrations of flammable gases or vapors could be communicated, unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air, and effective safeguards against ventilation failure are provided. FPN: The Zone 2 classification usually includes locations where volatile flammable liquids or flammable gases or vapors are used, but which would become hazardous only in case of an accident or of some unusual operating condition. 505-5 Material Groups. For purposes of testing, approval, and area classification, various air mixtures (not oxygen enriched) shall be grouped as required in (a), (b), and (c). FPN: Group I is intended for use in describing atmospheres that contain firedamp (a mixture of gases, composed mostly of methane, found underground, usually in mines). This Code does not apply to installations underground in mines. See Section 90-2(b). Group II shall be subdivided into IIC, IIB, and IIA, as noted in (a), (b), and (c), according to the nature of the gas or vapor, for protection techniques "d," "ia," "ib," "[ia]," and "[ib]," and, where applicable, "n" and "o." FPN No. 1: The gas and vapor subdivision as described above is based on the maximum experimental safe gap (MESG), minimum igniting current (MIC), or both. Test equipment for determining the MESG is described in Construction and Verification Tests of Flameproof Enclosures of Electrical Apparatus, IEC 79-1A-1975, Amendment No. 1 (1993) and UL Technical Report No. 58 (1993). The test equipment for determining MIC is described in Spark-Test Apparatus for Intrinsically-Safe Circuits, IEC 79-3-1990. The classification of gases or vapors according to their maximum experimental safe gaps and minimum igniting currents is described in Classification of Mixtures of Gases or Vapours with Air According to Their Maximum Experimental Safe Gaps and Minimum Igniting Currents, IEC 79-12-1978. FPN No. 2: Verification of electrical equipment utilizing protection techniques "e," "m," "p," and "q," due to design technique, does not require tests involving MESG or MIC. Therefore, Group II is not required to be subdivided for these protection techniques. FPN No. 3: It is necessary that the meanings of the different equipment markings and Group II classifications be carefully observed to avoid confusion with Class I, Divisions 1 and 2, Groups A, B, C, and D. (a) Class I Zone Group Classifications. Class I Zone groups shall be as follows: (1) Group IIC. Atmospheres containing acetylene, hydrogen, or flammable gas, flammable liquid-produced vapor, or combustible liquid-produced vapor mixed with air that may burn or explode, having either a maximum experimental safe gap (MESG) value less than or equal to 0.50 mm or minimum igniting current ratio (MIC ratio) less than or equal to 0.45. FPN: Group IIC is equivalent to a combination of Class I, Group A, and Class I, Group B, as described in Sections 500-5(a)(1) and (a)(2). (2) Group IIB. Atmospheres containing acetaldehyde, ethylene, or flammable gas, flammable liquid-produced vapor, or combustible liquid-produced vapor mixed with air that may burn or explode, having either maximum experimental safe gap (MESG) values

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greater than 0.50 mm and less than or equal to 0.90 mm or minimum igniting current ratio (MIC ratio) greater than 0.45 and less than or equal to 0.80. FPN: Group IIB is equivalent to Class I, Group C, as described in Section 500-5(a)(3). (3) Group IIA. Atmospheres containing acetone, ammonia, ethyl alcohol, gasoline, methane, propane, or flammable gas, flammable liquid-produced vapor, or combustible liquid-produced vapor mixed with air that may burn or explode, having either a maximum experiment safe gap (MESG) value greater than 0.90 mm or minimum igniting current ratio (MIC ratio) greater than 0.80. FPN: Group IIA is equivalent to Class I, Group D as described in Section 500-5(a)(4). 505-6 Special Precaution. Article 505 requires equipment construction and installation that will ensure safe performance under conditions of proper use and maintenance. FPN No. 1: It is important that inspection authorities and users exercise more than ordinary care with regard to the installation and maintenance of electrical equipment in hazardous (classified) locations. FPN No. 2: Low ambient conditions require special consideration. Electrical equipment depending on the protection techniques described by Section 505-4(a) may not be suitable for use at temperatures lower than -20ºC (-13ºF) unless they are approved for use at lower temperatures. However, at low ambient temperatures, flammable concentrations of vapors may not exist in a location classified Class I, Zones 0, 1, or 2 at normal ambient temperature. (a) Supervision of Work. Classification of areas and selection of equipment and wiring methods shall be under the supervision of a qualified Registered Professional Engineer. (b) Dual Classification. In instances of areas within the same facility classified separately, Class I, Zone 2 locations shall be permitted to abut, but not overlap, Class I, Division 2 locations. Class I, Zone 0 or Zone 1 locations shall not abut Class I, Division 1 or Division 2 locations. (c) Reclassification Permitted. A Class I, Division 1 or Division 2 location shall be permitted to be reclassified as a Class I, Zone 0, Zone 1, or Zone 2 location provided all of the space that is classified because of a single flammable gas or vapor source is reclassified under the requirements of this article. 505- 7 Protection Techniques. The following shall be acceptable protection techniques for electrical and electronic equipment in hazardous (classified) locations. FPN: For additional information, see Electrical Apparatus for Use in Class I, Zone 0, 1 Hazardous (Classified) Locations General Requirements, ISA S12.0.01-1997; Electrical Equipment for Use in Class I, Zone 0, 1, and 2 Hazardous (Classified) Locations, ANSI/UL 2279, 1997; and Electrical Apparatus for Explosive Gas Atmospheres - Part 0: General Requirements, IEC 79-0-1983, Amendment No. 1 (1987), and Amendment No. 2 (1991). (a) Flameproof "d." This protection technique shall be permitted for equipment in those Class I, Zone 1 locations for which it is approved. FPN No. 1: Flameproof is a type of protection of electrical equipment in which the enclosure will withstand an internal explosion of a flammable mixture that has penetrated into the interior, without suffering damage and without causing ignition, through any joints or structural openings in the enclosure, of an external explosive atmosphere consisting of one or more of the gases or vapors for which it is designed. FPN No. 2: For further information, see Electrical Apparatus for Use In Class I, Zone 1 and 2 Hazardous (Classified) Locations, Type of Protection -- Flameproof "d," ISA S12.22.01-1996; Electrical Apparatus for Explosive Gas Atmospheres, Part 1 -- Construction and Verification Test of Flameproof Enclosures of Electrical Apparatus, IEC 79-1-1990 and Amendment No. 1 (1993).

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(b) Purged and Pressurized. This protection technique shall be permitted for equipment in those Class I, Zone 1 or Zone 2 locations for which it is approved. FPN No. 1: In some cases, hazards may be reduced or hazardous (classified) locations limited or eliminated by adequate positive-pressure ventilation from a source of clean air in conjunction with effective safeguards against ventilation failure. FPN No. 2: For further information, see Standard for Purged and Pressurized Enclosures for Electrical Equipment, NFPA 496-1998. FPN No. 3: Pressurized "p" is a type of protection of electrical equipment that uses the technique of guarding against the ingress of the external atmosphere, which may be explosive, into an enclosure by maintaining a protective gas therein at a pressure above that of the external atmosphere. For further information, see Electrical Apparatus for Explosive Gas Atmospheres Part 2: Electrical Apparatus, Type of Protection "p," IEC 79-2-1983; and Electrical Apparatus for Explosive Gas Atmospheres - Part 13: Construction and Use of Rooms or Buildings Protected by Pressurization, IEC 79-13-1982. (c) Intrinsic Safety. This protection technique shall be permitted for equipment in those Class I, Zone 0 or Zone 1 locations for which it is approved. FPN No. 1: Intrinsic safety is designated type of protection "ia" by IEC 79-11 for use in Zone 0 locations. Intrinsic safety is designated type of protection "ib" by IEC 79-11 for use in Zone 1 locations. FPN No. 2: For further information, see Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I, II, and III, Hazardous Locations, ANSI/UL 913-1997; Electrical Apparatus for Explosive Gas Atmospheres -- Part 11: Intrinsic Safety "i," IEC 79-11-1991; and Electrical Apparatus for Explosive Gas Atmospheres -- Part 3: Spark-test Apparatus for Intrinsically-safe Circuits, IEC 79-3-1990. FPN No. 3: Intrinsically safe associated apparatus, designated by [ia] or [ib], is connected to intrinsically safe equipment ("ia" or "ib" respectively), but is located outside the hazardous (classified) location unless also protected by another type of protection (such as flameproof). (d) Type of Protection "n." This protection technique shall be permitted for equipment in those Class I, Zone 2 locations for which it is approved. Type of protection "n" is further subdivided into nA, nC, and nR. FPN No. 1: See Table 505-10(b) 1 for the descriptions of subdivisions for type of protection "n." FPN No. 2: Type "n" protection is a type of protection applied to electrical equipment such that, in normal operation, the electrical equipment is not capable of igniting a surrounding explosive gas atmosphere and a fault capable of causing ignition is not likely to occur. FPN No. 3: For further information, see Electrical Apparatus for Explosive Gas Atmospheres, Part 15 -- Electrical Apparatus with Type of Protection "n," IEC 7915-1987. (e) Oil Immersion "o." This protection technique shall be permitted for equipment in those Class I, Zone 1 locations for which it is approved. FPN No. 1: Oil immersion is a type of protection in which the electrical equipment or parts of the electrical equipment are immersed in a protective liquid in such a way that an explosive atmosphere that may be above the liquid or outside the enclosure cannot be ignited. FPN No. 2: For further information, see Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations, Type of Protection -- OilImmersion "o," ISA S12.26.01 -- 1996; and Electrical Apparatus for Explosive Gas Atmospheres, Part 6 -- OilImmersion "o," IEC 79-6-1995. (f) Increased Safety "e." This protection technique shall be permitted for equipment in those Class I, Zone 1 locations for which it is approved. FPN No. 1: Increased safety is a type of protection applied to electrical equipment that does not produce arcs or sparks in normal service and under specified abnormal conditions, in which additional measures are applied so as to give increased security against the

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possibility of excessive temperatures and of the occurrence of arcs and sparks. FPN No. 2: For further information, see Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations, Type of Protection -- Increased Safety "e," ISA S12.16.01-1996; and Electrical Apparatus for Explosive Gas Atmospheres -- Part 7: Increased Safety "e," IEC 79-7-1990, Amendment No. 1 (1991), and Amendment No. 2 (1993). (g) Encapsulation "m." This protection technique shall be permitted for equipment in those Class I, Zone 1 locations for which it is approved. FPN No. 1: Encapsulation is a type of protection in which the parts that could ignite an explosive atmosphere by either sparking or heating are enclosed in a compound in such a way that this explosive atmosphere cannot be ignited. FPN No. 2: For further information, see Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations Type of Protection -- Encapsulation "m," ISA S12.23.01-1996, and Electrical Apparatus for Explosive Gas Atmospheres -- Part 18: Encapsulation "m," IEC 79-18-1992. (h) Powder Filling "q." This protection technique shall be permitted for equipment in those Class I, Zone 1 locations for which it is approved. FPN No. 1: Powder filling is a type of protection in which the parts capable of igniting an explosive atmosphere are fixed in position and completely surrounded by filling material (glass or quartz powder) to prevent the ignition of an external explosive atmosphere. FPN No. 2: For further information, see Electrical Apparatus for Use in Class I, Zone 1 Hazardous (Classified) Locations Type of Protection -- Powder Filling "q," ISA S12.25.01-1996, and Electrical Apparatus for Explosive Gas Atmospheres -- Part 5: Powder Filling, Type of Protection "q," IEC 79-5-1967. 505-8 Equipment. (a) Listing. (1) Equipment that is listed for a Zone 0 location shall be permitted in a Zone 1 or Zone 2 location of the same gas or vapor. Equipment that is listed for a Zone 1 location shall be permitted in a Zone 2 location of the same gas or vapor. (2) Equipment shall be permitted to be listed for a specific gas or vapor, specific mixtures of gases or vapors, or any specific combination of gases or vapors. FPN: One common example is equipment marked for "IIB + H2." (b) Marking. Equipment shall be marked in accordance with (1) or (2). (1) Division Equipment. Equipment approved for Class I, Division 1 or Class I, Division 2 shall, in addition to being marked in accordance with Section 500-5(d), be permitted to be marked with the following: a. Class I, Zone 1 or Class I, Zone 2 (as applicable), and b. Applicable gas classification group(s) in accordance with Table 505-8(b)(2), and c. Temperature classification in accordance with Section 505-8(3) (2) Zone Equipment. Equipment meeting one or more of the protection techniques described in Section 505-4 shall be marked with the following in the order shown: a. Class b. Zone c. Symbol "AEx" d. Protection technique(s) in accordance with Table 505-8(b)(2) e. Applicable gas classification group(s) in accordance with Table 505-8(b)(2) f. Temperature classification in accordance with Section 505-8(c) Exception: Intrinsically safe associated apparatus shall be required to be marked only with (c), (d), and (e). FPN No. 1: An example of such a required marking is "Class I, Zone 0, AEx ia IIC T6." Electrical equipment of types of protection "e," "m," "p," or "q," shall be marked Group II. Electrical equipment of types of protection "d," "ia," "ib," "[ia]," or "[ib]" shall be marked Group IIA, or IIB, or IIC, or for a specific

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gas or vapor. Electrical equipment of types of protection "n" shall be marked Group II unless it contains enclosedbreak devices, nonincendive components, or energylimited equipment or circuits, in which case it shall be marked Group IIA, IIB, or IIC, or a specific gas or vapor. Electrical equipment of other types of protection shall be marked Group II unless the type of protection utilized by the equipment requires that it shall be marked Group IIA, IIB, or IIC, or a specific gas or vapor. FPN No. 2: An explanation of the marking that is required follows.

Figure 505-8(b)(1). Table 505-8(b)(1). Types of Protection Designation Designation Technique Zone* d Flameproof enclosure 1 e Increased safety 1 ia Intrinsic safety 0 ib Intrinsic safety 1 [ia] Intrinsically safe Nonhazardous associated apparatus [ib] Intrinsically safe Nonhazardous associated apparatus m Encapsulation 1 nA Nonsparking equipment 2 nC Sparking equipment in 2 which the contacts are suitably protected other than by restricted breathing enclosure enclosure nR Restricted breathing 2 o Oil immersion 1 p Purged and pressurized 1 or 2 q Powder filled 1 * Does not address use where a combination of techniques is used. Table 505-8(b)(2). Gas Classification Groups Gas Group Comment IIC See Section 505-5(a) IIB See Section 505-5(b) IIA See Section 505-5(c) (c) Class I Temperature. The temperature marking shall not exceed the ignition temperature of the specific gas or vapor to be encountered. FPN: For information regarding ignition temperatures of gases and vapors, see Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas, NFPA 497-1997; Guide to Fire Hazard Properties of Flammable Liquids, Gases, and Volatile Solids, NFPA 325-1994; and Electrical Apparatus for Explosive Gas Atmospheres, Data for Flammable Gases and Vapours, Relating to the Use of Electrical Apparatus, IEC 79-20-1996. (1) Temperature Classifications. Approved equipment shall be marked to show the operating temperature or temperature range referenced to a 40ºC (104ºF) ambient. The temperature range, if provided, shall be indicated in identification numbers, as shown in Table 505-8 (c). Table 505-8(c). Classification of Maximum Surface Temperature for Group II Electrical Equipment Temperature Maximum Surface Class Temperature (ºC) T1 Û450 T2 Û300 T3 Û200 T4 Û135 T5 Û100 T6 Û85

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Electrical equipment designed for use in the ambient temperature apply only to Class I materials. If ever finalized and adopted, zones range between -20ºC and +40ºC shall require no additional that address combustible dusts will have a different numbering temperature marking. system (i.e., Zone 20, 21, 22). Electrical equipment that is designed for use in a range of ambient PANEL ACTION: Reject. temperatures other than -20ºC and +40ºC is considered to be PANEL STATEMENT: Class I designation has been accepted for special; and the ambient temperature range shall then be marked the past several code cycles and has been used successfully by on the equipment, including either the symbol "Ta" or "Tamb" manufacturers and product evaluation and testing organizations. together with the special range of ambient temperatures. As an NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 example, such a marking might be "-30ºC Ta + 40ºC." VOTE ON PANEL ACTION: Electrical equipment suitable for ambient temperatures exceeding AFFIRMATIVE: 12 40ºC (104ºF) shall be marked with both the maximum ambient NOT RETURNED: 2 Earley, Saban temperature and the operating temperature or temperature range at that ambient temperature. ___________________ Exception No. 1: Equipment of the nonheat-producing type, such as conduit fittings, and equipment of the heat-producing type having a maximum temperature of not more than 100ºC (212ºF) shall not be (Log #37) required to have a marked operating temperature or temperature range. 322 - (505-3, FPN (New) ): Reject 14Exception No. 2: Equipment approved for Class I, Division 1 or Division NOTE: The following proposal consists of Comment 14-72 on 2 locations as permitted by Sections 505-20(b) and (c) shall be permitted Proposal 14-281 in the 1998 Annual Meeting National Electrical to be marked in accordance with Section 500-5(d) and Table 500-5(d). Code Committee Report on Proposals. This comment was held for further study during the processing of the 1999 NATIONAL (d) Threading. All threaded conduit referred to herein shall be ELECTRICAL CODE. The recommendation in Proposal 14-281 threaded with an NPT standard conduit cutting die that provides was: 3/4-in. taper per foot. Such conduit shall be made wrenchtight to Revise as follows: prevent sparking when fault current flows through the conduit 505-3. Special Precaution. Article 505 requires equipment system, and to ensure the explosionproof or flameproof integrity of construction and installation that will ensure safe performance the conduit system where applicable. under conditions of proper use and maintenance. Equipment provided with threaded entries for field wiring (FPN No. 1): It is important that inspection authorities and users connections shall be installed in accordance with (1) or (2). exercise more than ordinary care with regard to installation and (1) Equipment Provided with Threaded Entries for NPT Threaded maintenance of electrical equipment in hazardous (classified) Conduit or Fittings. For equipment provided with threaded entries locations. for NPT threaded conduit or fittings, listed conduit, conduit (FPN No. 2): Low ambient conditions require special fittings, or cable fittings shall be used. consideration. Electrical equipment depending on the protection (2) Equipment Provided with Threaded Entries for Metric techniques described by 505-2(c)1 may not be suitable for use at Threaded Conduit or Fittings. For equipment with metric threaded temperatures lower than -20°C (-13°F) unless they are approved for entries, such entries shall be identified as being metric, or listed use at lower temperatures. However, at low ambient temperatures, adapters to permit connection to conduit or NPT-threaded fittings flammable concentrations of vapors may not exist in a location shall be provided with the equipment. Adapters shall be used for classified Class I, Zones 0, 1, or 2 at normal ambient temperature. connection to conduit or NPT-threaded fittings. Listed cable (a) Supervision of Work. Classification of areas and selection of fittings that have metric threads shall be permitted to be used. equipment and wiring methods shall be under the supervision of a FPN: Threading specifications for metric threaded qualified Registered Professional Engineer. entries are located in Metric Screw Threads, ISO (b) Dual Classification. Class I, Zone 2 locations shall be 965/1:1980, and Metric Screw Threads, ISO 965/3:1980. permitted to abut, but not overlap, Class I, Division 2 locations. SUBSTANTIATION: Currently, the introduction to Hazardous Class I, Zone 0 or Zone 1 locations shall not abut Class I, Division (Classified) Locations is presented with little regard to clarity and 1 or Division 2 locations. understanding. The text jumps from "classifications" to (c) Reclassification Permitted. A Class I, Division 1 or Division 2 "documentation" to "threaded...", to "protection techniques", location shall be permitted to be reclassified as a Class I, Zone 0, without ever providing groundwork as to the need for the Zone 1 or Zone 2 location provided all of the space that is protection techniques. Under the proposed revision, the reader is classified because of a single flammable gas or vapor source is moved in a logical sequence, that defines general needs, addresses reclassified under the requirements of this article. the classifications of locations, discusses material groups, before SUBMITTER: Zdena Zajickova, World Safety Org. ever mentioning equipment. Then with protection techniques, RECOMMENDATION: Add Fine Print Note following 505-3 equipment, equipment approvals, equipment markings and statement: equipment designs are addressed. This provides a flow into the "Classification of areas and selection of equipment and wiring more specific sections beyond Article 505. methods shall be under the supervision of a qualified Registered PANEL ACTION: Accept in Principle. Professional Engineer." PANEL STATEMENT: Proposal 14-318a addresses the submitter's (FPN): The term "Qualified Registered Professional Engineer" proposed rewrite with one developed by Panel 14. may be considered applicable to qualified members of the World NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 Safety Organization certified by the WSO Professional Certification VOTE ON PANEL ACTION: Board. AFFIRMATIVE: 11 SUBSTANTIATION: The World Safety Organization (WSO) is in NEGATIVE: 1 Consultative Status Category II (nongovernmental) with the United NOT RETURNED: 2 Earley, Saban Nations; and as such is fully recognized throughout the world as a EXPLANATION OF NEGATIVE: professional organization. Its roster includes over 14,000 members, COOK: Although I agree with a reorganization effort, this 1500 national and multinational companies/corporations, and 184 proposal seems incomplete. Sections 505-20, 21, and 25 seem to be nations. Also included are over 2,000 professionals who are both left out. nationally and internationally certified practitioners in the safety, health and environmental vocations. Since 1975, this organization ___________________ has been strongly committed to the protection of people, property, resources and the environment. The WSO mandates an evaluation of its members mastery of safety knowledge and application; to (Log #2265) include their professional and ethical behavior. Strict standards of 14- 321 - (505): Reject professional performance are applied to ensure that WSO certified SUBMITTER: David Wechsler, Union Carbide Corp. members, practicing safety, have attained a level of professionalism RECOMMENDATION: Delete "Class I" before the term zone, in required to meet or exceed the needs of Government, commerce, all 13 places that it appears within the NEC. Thus, for example, and industry on both national and international levels. I have "Class I, Zone 1" would now become simply "Zone 1." provided more information about the WSO and our certification SUBSTANTIATION: Unlike the US Class-Division methodology exams, policy, and program. where a division could apply to flammable gases or to combustible Note: Supporting material is available for review at NFPA dusts, and thus required the "Class" for appropriate understanding, Headquarters. "Zone 0," "Zone 1," "Zone 2" can only apply to Class I materials. PANEL ACTION: Reject. Thus, the use of the term "Class I" before the "zone" term is PANEL STATEMENT: See Proposal 14-348, which deletes this unnecessary and extraneous since "Zone 0," "FZone 1," "Zone 2" section.

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NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3020) 14- 323 - (505-3(a), FPN No. 2): Accept in Principle SUBMITTER: Kari Barrett, Chemical Manufacturers Assn. RECOMMENDATION: Replace "nonhazardous" with "unclassified." SUBSTANTIATION: This is a companion proposal to other proposals which provide a definition of unclassified in Articles 100, 500, and 505, and provides correlation. The term "Classified" refers to the type of material/hazard potential involved, i.e., Class I, Division 1, Class II, Division 2, etc. Terms such as nonhazardous and unclassified are used in both the NEC, the Uniform Building Code (UBC), and other NFPA documents. The term nonhazardous infers that the area has "no" hazards while the term "unclassified" more clearly correlates with the condition of being reviewed but found not to need classification. This action provides needed correlation with other NFPA documents, such as NFPA 497. Additionally the term "nonhazardous" is used 7 times within various parts of the NEC, and in at least one place in the NEC the meaning of nonhazardous applies to voltages and not classification. A companion proposal has been made to change the term "nonhazardous" to "unclassified" as appropriate elsewhere in the NEC. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-318a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3984) 14- 324 - (505-3(b)(1)): Accept in Principle SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL RECOMMENDATION: Revise text to read as follows: 505-3(b)(1) Equipment Provided with Threaded Entries for NPT Threaded Conduit or Fittings. For equipment provided with threaded entries for NPT threaded conduit or fittings, listed conduit, conduit fittings, or cable fittings shall be used. Threaded entries into flameproof or explosionproof enclosures shall be made up with at least five threads fully engaged. SUBSTANTIATION: This proposal is the work of a Task Group including Ed Briesch, Bill Lawrence, Dave Wechsler, Lon Ballard, Larry Fuhrman, and Will McBride. This Task Group was not balloted. The purpose of the proposal is to provide clear guidelines for wiring, sealing, and installation in Article 505, without having to refer to Article 501. PANEL ACTION: Accept in Principle. PANEL STATEMENT: Proposal 14-318a addresses this issue. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #1628) 14- 325 - (505-4(a)): Accept in Part SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise first sentence to read as follows: This protection technique shall be permitted for equipment in those Class I, Zone 1 locations for which it is approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based 14

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on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. PANEL STATEMENT: Proposal 14-318a addresses the issues in this proposal. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3571) 14- 326 - (505-4(a)): Accept in Part SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the first sentence to read as follows: "This protection technique shall be permitted for equipment in those Class I, Zone 1 locations for which it is approved (identified)." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. PANEL STATEMENT: Proposal 14-318a addresses the issues in this proposal. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1629) 14- 327 - (505-4(b)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise first sentence to read as follows: This protection technique shall be permitted for equipment in those Class I, Zone 1 or Zone 2 locations for which it is approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________

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(Log #3572) 14- 328 - (505-4(b)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the first sentence to read as follows: "This protections technique shall be permitted for equipment in those Class I, Zone 1 or Zone 2 locations for which it is approved (identified)." SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1630) 14- 329 - (505-4(c)): Accept SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise first sentence to read as follows: This protection technique shall be permitted for equipment in those Class I, Zone 0 or Zone 1 locations for which it is approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3573) 14- 330 - (505-4(c)): Accept SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the first sentence to read as follows: (c) Intrinsic Safety. This protection technique shall be permitted for equipment in those Class I, Zone 0 or Zone 1 locations for which it is approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept. PANEL STATEMENT: Acceptance of this proposal is contingent upon acceptance of the Fine Print Note to the definition of "Identified" in Proposal 14-4a. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION:

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AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1631) 14- 331 - (505-4(d)): Accept in Part SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise first sentence to read as follows: (d) Type of Protection "n." This protection technique shall be permitted for equipment in those Class I, Zone 2 locations for which it is approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. PANEL STATEMENT: Proposal 14-318a addresses the issues in this proposal. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #2526) 14- 332 - (505-4(d)): Reject SUBMITTER: Nicholas Ludlam, Factory Mutual Research RECOMMENDATION: Revise as follows: (d) Type of Protection "n." This protection technique shall be permitted for equipment in those Class 1, Zone 2 locations for which it is approved. Type of protection "n" is further subdivided into nA, nC, nL , and nR. FPN No. 1: See Table 505-10(b) (1) for the descriptions of subdivisions for type of protection "n". FPN No. 2: Type "n" protection is a type of protection applied to electrical equipment such that, in normal operation, the electrical equipment is not capable of igniting a surrounding explosive gas atmosphere and a fault capable of causing ignition is not likely to occur. FPN No. 3: For further information, see Electrical Apparatus for Explosive Gas Atmospheres, Part 15 - Electrical Apparatus with Type of Protection "n" IEC 79-15-1987.

Table 505-10(b)1 Designation d e ia ib [ia] [ib] m nA nC Technique Flameproof Enclosure Increased safety Intrinsic safety Intrinsic safety Intrinsically safe associated apparatus Intrinsically safe associated apparatus Encapsulation Nonsparking equipment Sparking equipment in which the contacts are suitably protected other than by restricted-breathing enclosure, and energy limitation. energy-limited equipment. Restricted breathing enclosure Oil immersion Purged and pressurized Powder filled Zone* 1 1 0 1 Nonhazardous Nonhazardous 1 2 2

nL nR o P q

2 2 1 1 or 2 1

*Does not address use where a combination of techniques is used.

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SUBSTANTIATION: The draft IEC 60079-15 which is currently being prepared as an FDIS and on which ISA S12.12.02 will be based has an extra category for Type N apparatus. This is Ex nL of Energy limited. This concept is similar to the nonincendive field wiring apparatus currently permitted in Article 501-4(b) of the 1999 National Electrical Code. PANEL ACTION: Reject. PANEL STATEMENT: The referenced document is not yet published. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #2527) 14- 333 - (505-4(d)): Reject SUBMITTER: Nicholas Ludlam, Factory Mutual Research RECOMMENDATION: (d) Type of Protection "n." This protection technique shall be permitted for equipment in those Class I, Zone 2 locations for which it is approved. Type of protection "n" is further subdivided into nA, nC, nL, and nR. FPN No. 1: See Table 505-10(b) 1 for the descriptions of subdivisions for type of protection "n." FPN No. 2: Type "n" protection is a type of protection applied to electrical equipment such that, in normal operation, the electrical equipment is not capable of igniting a surrounding explosive gas atmosphere and a fault capable of causing ignition is not likely to occur. FPN No. 3: For further information, see Electrical Apparatus for Explosive Gas Atmospheres, Part 15 -- Electrical Apparatus with Type of Protection "n," IEC 60079-15. SUBSTANTIATION: The addition of the "nL" for Energy Limited Apparatus is necessary as this is included within the next edition of IEC60079-15. IEC60079-15 will shortly be published as an FDIS and will be available by the time the 2002 Code is published. PANEL ACTION: Reject. PANEL STATEMENT: The referenced document is not yet published. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 12 NOT RETURNED: 2 Earley, Saban ___________________ (Log #3570) 14- 334 - (505-4(d)): Accept in Part SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the first sentence to read as follows: (d) Type of Protection "n." This protection technique shall be permitted for equipment in those Class I, Zone 2 locations for which it is approved (identified). Type or protection "n" is further subdivided into nA, nC, and nR. SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. PANEL STATEMENT: Proposal 14-318a addresses the issues in this proposal. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1632) 14- 335 - (505-4(e)): Accept in Part SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise first sentence to read as follows: (e) Oil Immersion "o." This protection technique shall be

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permitted for equipment in those Class I, Zone 1 locations for which it is approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. PANEL STATEMENT: Proposal 14-318a addresses the issues in this proposal. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________ (Log #3569) 14- 336 - (505-4(e)): Accept in Part SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the first sentence to read as follows: (e) Oil Immersion "o." This protection technique shall be permitted for equipment in those Class I, Zone 1 locations for which it is approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP-14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. PANEL STATEMENT: Proposal 14-318a addresses the issues in this proposal. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. ___________________ (Log #1633) 14- 337 - (505-4(f)): Accept in Part SUBMITTER: Donald R. Cook, Shelby County Building Insp., AL/Rep. Southern Section, IAEI RECOMMENDATION: Revise first sentence to read as follows: (f) Increased Safety "e." This protection technique shall be permitted for equipment in those Class I, Zone 1 locations for which it is approved (identified). SUBSTANTIATION: If approved is the desired requirement of CMP 14, it is already required by Section 110-2. If the panel desires that this equipment, or technique be suitable for some specific purpose, then "identified" would be a more accurate term, based on Article 100, NEC definitions. The authority having jurisdiction would have no basis for approval of the equipment or technique unless it was suitable for the specific purpose. PANEL ACTION: Accept in Part. PANEL STATEMENT: Proposal 14-318a addresses the issues in this proposal. NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 14 VOTE ON PANEL ACTION: AFFIRMATIVE: 11 NEGATIVE: 1 NOT RETURNED: 2 Earley, Saban EXPLANATION OF NEGATIVE: ZIPSE: See my Explanation of Negative Vote on Proposal 14-13. COMMENT ON AFFIRMATIVE: WECHSLER: See my Comment on Affirmative Vote on Proposal 14-13. ___________________

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(Log #3568) 14- 338 - (505-4(f)): Accept in Part SUBMITTER: Philip H. Cox, Int'l Assn. of Electrical Inspectors RECOMMENDATION: Revise the first sentence to read as follows: (f) Increased Safety "e." This protection technique sh