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Report on Comments -- Copyright, NFPA

Report of the Committee on Lightning Protection Mitchell Guthrie, Chair Universal Systems Inc., NC [SE] Gerard M. Berger, CNRS - Supelec, France [SE] Ignacio T. Cruz, Cruz Associates, Inc., VA [SE] Franco DAlessandro, ERICO, Inc., OH [M] Dennis P. Dillon, Bonded Lightning Protection, Inc., FL [IM] Rep. Lightning Protection Institute Douglas J. Franklin, Thompson Lightning Protection Inc., MN [M] John R. Fredlund, US Department of Energy/NA-53, DC [E] Thomas R. Harger, Harger Lightning Protection Inc., IL [M] William E. Heary, Lightning Preventors of America Inc., NY [IM] Bruce A. Kaiser, Lightning Master Corporation, FL [M] Norbert S. Klekowski, BP p.l.c., IL [U] Rep. American Petroleum Institute Richard W. Kragh, Kragh Engineering Inc., IL [SE] Joseph A. Lanzoni, Lightning Eliminators & Consultants Inc., CO [M] Edward A. Lobnitz, Tilden Lobnitz Cooper Inc., FL [SE] Eduardo Mariani, Datawaves SRL, Argentina [SE] David E. McAfee, Fire and Lightning Consultants, GA [SE] R. B. Melton, Jr., BellSouth Telecommunications, Inc., GA [U] Rep. Alliance for Telecommunications Industry Solutions Terrance K. Portfleet, Michigan Lightning Protection Company, MI [IM] Rep. United Lightning Protection Association, Inc. Robert W. Rapp, National Lightning Protection Corp., CO [M] Dick Reehl, Qwest, WA [U] William Rison, New Mexico Institute of Mining & Technology, NM [SE] Timothy E. Russell, Underwriters Laboratories Inc., IL [RT] Lon D. Santis, Institute of Makers of Explosives, DC [U] Larry W. Strother, US Air Force, FL [E] John M. Tobias, US Department of the Army, NJ [U] Charles L. Wakefield, US Department of the Navy, MD [E] Donald W. Zipse, Zipse Electrical Engineering Inc., PA [U] Rep. Institute of Electrical & Electronics Engineers, Inc. Alternates Charles H. Ackerman, East Coast Lightning Equipment Inc., CT [IM] (Alt. to Dennis P. Dillon) Peter A. Carpenter, Lightning Eliminators & Consultants Inc., CO [M] (Alt. to Joseph A. Lanzoni) Dennis Dyl, Kragh Engineering Inc., IL [SE] (Alt. to Richard W. Kragh)

Timothy R. Harger, Harger Lightning Protection, Inc., IL [M] (Alt. to Thomas R. Harger) Kenneth P. Heary, Lightning Preventor of America Inc., NY [IM] (Alt. to William E. Heary) Paris M. Hudspeth, Underwriters Laboratories Inc., IL [RT] (Alt. to Timothy E. Russell) Stephen Humeniuk, Warren Lightning Rod Company, NJ [IM] (Alt. to Terrance K. Portfleet) Christopher R. Karabin, US Department of the Navy, MD [E] (Alt. to Charles L. Wakefield) David John Leidel, Halliburton Energy Services, TX [U] (Alt. to Lon D. Santis) Charles B. Moore, New Mexico Institute of Mining & Technology, NM [SE] (Alt. to William Rison) Allan P. Steffes, Thompson Lightning Protection Inc., MN [M] (Alt. to Douglas J. Franklin) Antony J. Surtees, ERICO, Incorporated, OH [M] (Alt. to Franco DAlessandro) Paul R. Svendsen, National Lightning Protection Corporation, CO [M] (Alt. to Robert W. Rapp) Staff Liaison: Richard Roux

NFPA 780

Committee Scope: This Committee shall have primary responsibility for documents on the protection from lightning of buildings and structures, recreation and sports areas, and any other situations involving danger from lightning to people or property, except those concepts utilizing early streamer emission air terminals. The protection of electric generating, transmission, and distribution systems is not within the scope of this Committee. This list represents the membership at the time the Committee was balloted on the text of this edition. Since that time, changes in the membership may have occurred. A key to classifications is found at the front of this book. This portion of the Technical Committee Report of the Committee on Lightning Protection is presented for adoption. This Report on Comments was prepared by the Technical Committee on Lightning Protection, and documents its action on the comments received on its Report on Proposals on NFPA 780, Standard for the Installation of Lightning Protection Systems, 2000 edition, as published in the Report on Proposals for the 2004 May Meeting. This Report on Comments has been submitted to letter ballot of the Technical Committee on Lightning Protection, which consists of 27 voting members. The results of the balloting, after circulation of any negative votes, can be found in the report.

780-1

Report on Comments -- Copyright, NFPA

________________________________________________________________ 780-1 Log #CC3 Final Action: Accept ( Entire Document ) ________________________________________________________________ Submitter: Technical Committee on Lightning Protection Comment on Proposal No: 780-1 Recommendation: In the NFPA 780 "Draft" document, change the following: In Section 4.13.5.2, Change "0.5 m" to "460 mm" In Section 4.13.6.2, Change "0.5 m" to "460 mm" In Section 8.2.4, Change "0.610 m" to "0.6 m" In Section 4.10 ,Change "1 m" to "0.9 m" In Section 6.5.3, Change "13 mm" to "12.7 mm" In Section 4.7.2.3, Change "15.24 m" to "15 m" In Section Fig 4.7.2.3(a) Change "15.24 m" to "15 m" In Section Fig 4.7.2.3(b Change "15.24 m" to "15 m" In Section F.1.3, Change "15.24 m" to "15 m" In Section 6.9.2, Change "15.9 mm" to "15 mm" In Section K.1.1.3, Change "153 mm" to "152 mm" In Section C.2.1, Change "2 m" to "1.8 m" In Section F.1.3, Change "22 m" to "23 m" In Section 4.13.5.2, Change "3.7 m" to "3.6 m" In Section J.4.2.2, Change "30.5 m" to "30 m" In Section J.4.2.2, Change "30.5 m" to "30 m" In Section J.2, Change "33 m" to "30 m" In Section J.3.3, Change "33 m" to "30 m" In Section 4.6.1.2, Change "4.8 mm" to "4.88 mm" In Section 4.8.8, Change "4.8 mm" to "4.88 mm" In Section 4.8.8.1, Change "4.8 mm" to "4.88 mm" In Section 4.9.3.3, Change "4.8 mm" to "4.88 mm" In Section 6.3.5.1, Change "4.8 mm" to "4.88 mm" In Section 6.10.1, Change "4.8 mm" to "4.88 mm" In Section 7.1.2.1, Change "4.8 mm" to "4.88 mm" In Section 7.3.2, Change "4.8 mm" to "4.88 mm" In Section 7.4.1.1(D), Change "4.8 mm" to "4.88 mm" In Section 4.5.2.2, Change "457 mm" to "460 mm" In Section 4.13.4*, Change "457 mm" to "460 mm" In Section 6.8.2.1, Change "50 m" to "46 m" In Section 4.13.3.1, Change "50.8 mm" to "50 mm" In Section 7.4.1.2(A), Change "51 mm" to "50 mm" In Section 4.13.3.2(1), Change "6.1 m" to "6 m" In Section 4.13.3.2(2), Change "6.1 m" to "6 m" In Section 4.13.4.1, Change "6.1 m" to "6 m" In Section K.1.2, Change "6.1 m" to "6 m" In Section 6.4.2.4, Change "67 m" to "60 m" In Section 6.7.1, Change "67 m" to "60 m" In Section 6.8.1.3, Change "67 m" to "60 m" In Section 7.3.3.7(B), Change "67 m" to "60 m" In Section J.4.2.2, Change "76.2 m" to "76 m" Substantiation: The Technical Committee made these SI changes to comply with the NFPA MOS 4.1. Committee Meeting Action: Accept Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP ________________________________________________________________ 780-2 Log #CC4 Final Action: Accept ( Entire Document ) ________________________________________________________________ Submitter: Technical Committee on Lightning Protection Comment on Proposal No: 780-1 Recommendation: In the NFPA 780 "Draft" document, change the following: In Section 4.13.8.1.3, "...0.032 in. (0.8 mm)..." to "...0.8 mm (0.032 in.)..." In Section 4.13.8.1.1, "...1 ft (0.3 m)..." to "...0.3 m (1 ft)..." in two places In Section L.2.5(1), "...1 ft (0.3 m)..." to "...0.3 m (1 ft)..." In Section L.2.5(1), "...10 ft (3 m)..." to "...3 m (10 ft)..." In Section 4.13.8.1.1, "...2 ft (0.6 m)..." to "...0.6 m (2 ft)..." in two places In Section 4.13.8.1.2, "...2 ft (0.6 m)..." to "...0.6 m (2 ft)..." In Section 4.13.8.1.4, "...2 ft (0.6 m)..." to "...0.6 m (2 ft)..." In Section 4.13.8.1.3, "...2 ft2 (0.18 m2)..." to "...0.18 m2 (2 ft2)..." Substantiation: The Technical Committee made these SI changes to comply with the NFPA MOS 4.1. Committee Meeting Action: Accept Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP Comment on Affirmative: GUTHRIE: In Section 4.13.8.1.3, the entry "2 ft2 (0.18 m2) ... to 0..18 m2 (2 ft2 )... " should read "2 ft2 (0.18 m2)... to 0.18 m2 (2 ft2)..."

________________________________________________________________ 780-3 Log #CC5 Final Action: Accept ( Entire Document ) ________________________________________________________________ Submitter: Technical Committee on Lightning Protection Comment on Proposal No: 780-1 Recommendation: In the NFPA 780 "Draft" document, change the following: Delete Asterisk after Section 3.3.22 as there is no Annex item. Renumber 3.3.33.4 and 3.3.33.5 as there is no 3.3.33.3. Remove indent from Section 4.1.1.2. Change Section 4.13.8.1.5 to read: "4.13.8.1.5 In those cases where the grounding conductor is laid directly on bedrock, the conductor shall be secured to the bedrock at every 1 m (3 ft) by nailing, conductive cement, or a conductive adhesive to ensure electrical contact and protect against movement." Change Section 4.18.5 to 4.18.5* in order to reflect reference to A.4.18.5. Change Section 7.3.1.2 to read: "7.3.1.2 Overhead ground wire material shall be chosen to minimize corrosion from conditions at the site." Delete 2nd A.4.18.2 "The SPD responds ... and air temperature." (Note - this 2nd item pertained to NFPA 780-2000 3.18 which was replaced by A.4.18.2). Delete Asterisk after Section 7.3.3.1 as there is no Annex item. Change A.7.3.3.7 to A.7.3.3.8. Substantiation: The Technical Committee notes several typos in the NFPA 780 "Draft" document. Committee Meeting Action: Accept Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP

NFPA 780

________________________________________________________________ 780-4 Log #CC7 Final Action: Accept ( 1.5 ) ________________________________________________________________ Submitter: Technical Committee on Lightning Protection Comment on Proposal No: 780-1 Recommendation: Add Section 1.5 to read as follows: "1.5 Maintenance. Recommended guidelines for the maintenance of the lightning protection system shall be provided to the owner at the completion of installation. Guidance on the content of an effective maintenance program are provided in Annex E." Renumber following sections. Substantiation: The Technical Committee realizes that maintenance is essential for continued system performance. There was previously a section in NFPA 780-2000 entitled Maintenance. This section was mistakenly omitted from the NFPA 780 "Draft" document. It is the TCs intent to retain this in the body of the document. Committee Meeting Action: Accept Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP ________________________________________________________________ 780-5 Log #7 Final Action: Accept in Principle ( 2.2 Definitions (GOT) ) ________________________________________________________________ Submitter: Timothy E. Russell, Underwriters Laboratories Inc. Comment on Proposal No: 780-4 Recommendation: Retain the "secondary" definitions for 3.2.2 Bonding, 3.2.3* Cable, 3.2.4 Chimney, 3.2.11 Fastener, and 3.2.20 High-Rise Building. Substantiation: The existing "secondary" definitions stated in NFPA 780, 2000 Edition, define these terms as they specifically apply to the NFPA 780 Standard. Changing to the "preferred" definitions will result in incorrect, or at least inadequate information for those using the NFPA 780 Standard. Note: Supporting material is available for review at NFPA Headquarters. Committee Meeting Action: Accept in Principle Change the following definitions as shown: "3.3.1 Bonding. An electrical connection between an electrically conductive object and a component of a lightning protection system that is intended to significantly reduce potential differences created by lightning currents." "3.3.2* Cable. A conductor formed of a number of wires stranded together." "3.3.3 Chimney. A smoke or vent stack having a flue with a cross-sectional area less than 0.3 m2 (500 in.2) and a total height of 23 m (75 ft) or less." "3.3.7 Fastener. An attachment device used to secure the conductor to the structure." "3.3.15 High-Rise Building. A structure exceeding 23 m (75 ft) in height." Committee Statement: The Committee agrees with the submitter that the original definitions for "Bonding", "Cable", "Chimney", "Fastener", and "High-Rise Building" must be retained from NFPA 780-2000. Although these words are well defined in the NFPA Glossary of Terms, they have specific/ unique meanings as used in this standard. The Committee made SI changes to comply with the NFPA MOS 4.1. Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP

780-2

Report on Comments -- Copyright, NFPA

________________________________________________________________ 780-6 Log #CC8 Final Action: Accept ( 3.3.5.3 ) ________________________________________________________________ Submitter: Technical Committee on Lightning Protection Comment on Proposal No: 780-1 Recommendation: Change Section 3.3.5.3 to reflect reference to Annex A as follows: "3.3.5.3* Main Conductor." Add to Annex A as follows: "A.3.3.5.3 Main Conductor. The main conductor also serves as a strike termination device for catenary lightning protection systems." Substantiation: The Technical Committee notes that in the NFPA 780 "Draft" document, the definition of Main Conductor has changed. The second sentence was mistakenly omitted from the NFPA 780 "Draft" document. It is the TCs intent to locate this second sentence in the Annex. Committee Meeting Action: Accept Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP

ERICO restates its position as follows: "ERICO has sought to act with proprietary concerning the submission (and subsequent withdrawal) of this proposal on the Collection Volume Method, Log #12. It has sought to withdraw this submission to allow the body of work to be returned to the Modeling Task Force for further evaluating its applicability. This action has been taken in good faith as an attempt to engender greater participation by interested parties in further evaluating its applicability.The action taken should in no way be construed to depict that the proposal is "deemed to lack validation". Rather the action is intended to allow opportunity for greater evaluation of the method proposed." ERICO agrees with the committee position as stated on the ballot i.e. that the body of work will be returned to the Modeling Task force for further evaluation.

NFPA 780

________________________________________________________________ 780-8 Log #3 Final Action: Reject ( 3.9.3 ) ________________________________________________________________ Submitter: Mitchell Guthrie, Universal Systems, Inc. Comment on Proposal No: 780-11 ________________________________________________________________ Recommendation: Delete proposed revision allowing the use of handrails and 780-7 Log #8 Final Action: Reject ladders as a substitute for down conductors. ( 3.7.4 (New) ) Substantiation: While it is agreed that the ladders and handrails should ________________________________________________________________ be bonded to the lightning protection system at their extremities and the Submitter: Franco DAlessandro, Erico Inc. surge impedance of the items is likely to be less than that for typical down Comment on Proposal No: 780-7 conductors, there is an inherent risk in the use of the items as a replacement Recommendation: (1) Committee Statement should read as follows: for required down conductors. There is a reasonable probability that the owner "The submitter has asked that the proposal be withdrawn at this time. The or user of the structure may move, replace, or eliminate these items during proposal will undergo further evaluation by the Modeling Task Force during the lifetime of the structure without knowledge that they play an integral role the next revision cycle." in the lightning protection system. The result will be fewer than the required (2) Replies to respondents: minimum number of down conductors for the structure. This is not a risk (a) Comment on Affirmative - Mr. Dillon worth taking. It is always better to have more down conductors than required 1. Reference is made to the "submitter" in this paragraph. It is assumed that than to be left with less than required. this party is intended to refer to Mr. ZIPSE (and his Explanation of Negative). Committee Meeting Action: Reject 2. A statement is made that, "the Scientific Committee of the International Committee Statement: The submitter has not provided sufficient Conference on Lightning Protection reviewed this same proposal last substantiation. September and issued a statement concluding that the CVM concept lacks The Committee will continue to allow the use of of permanent handrails and sufficient validation." The wording in this statement may have been ladders per ROP 780-11 (Log #7). unintentionally misinterpreted. The Scientific Committee of the International Number Eligible to Vote: 27 Conference on Lightning Protection in their statement stated "...the methods Ballot Results: Affirmative: 20 Negative: 3 are still under discussion and debate" and "...it is recommended to postpone the Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP inclusion (of the CVM/FIM) in the new standard (AS1768) until consensus in Explanation of Negative: the international scientific community has been achieved". In other words, the GUTHRIE: I do not concur with the Committee Action nor substantiation method proposed by the submitter is still to be evaluated. provided. The risk of removal of these items without the understanding Substantiation: Mr. Erico has sought to act with proprietary concerning the that they are an essential part of the lightning protection system is sufficient submission (and subsequent withdrawal) of this proposal on the Collection substantiation to not allow that they be used as a substitute for main Volume Method, Proposal 780-7 (Log #12). It has sought to withdraw this conductors. Comment 780-9 (Log #11) also provides an example of technical submission to allow the body of work to be returned to the Modeling Task issues that must be addressed if handrails and ladders are used in lieu of main Force for further evaluation. This action has been taken in good faith as conductors. It is far better to provide more main conductors than the minimum an attempt to engender greater participation by interested parties in further number required than it is to risk the possibility that fewer than the minimum evaluating its applicability. The action taken should in no way be construed to acceptable number of main conductors may exist; especially if the continuity of depict that the proposal is "deemed to lack validation". Rather, the action is any substituted conductors may be suspect. intended to allow opportunity for greater evaluation of the method proposed. KLEKOWSKI: I disagree with the Committees action to reject this Since the submitter sought to withdraw this proposal in good faith, and since comment and accept the original proposal. The original Proposal 780-11 committee governance only allows a tabled proposal to be "Accepted" or should not be accepted. Ladders and handrails are presently intended and "Rejected", the committee acted to "Reject" in compliance with the request of designed to facilitate safe climbing and walking. Assuming ladders and the submitter. It is important that these issues be clarified and responded to handrails are adequate conductors without defining minimum electrical at the ROC to prevent misinterpretation by outside parties of the Committees standards (design, construction, and inspection) for these primarily nonaction, in light of the request to withdraw by the submitter. electrical systems increases risk. Therefore, the Committees action to reject Committee Meeting Action: Reject Comment 780-8 and accept Proposal 780-11 results in increased risk. Committee Statement: The Committee understands the nature of submitters ZIPSE: I agree with the submitters substantiation, Mitchell Gurthrie. The comment. The NFPA Regulations Governing Committee Projects, 4-3.4, use of handrails can be detrimental to the safety of the structure. In addition, describes the procedure for withdrawal of a proposal. the connection to the handrails can pose hazards to persons using the handrail The submitter has not proposed a change to the document. due to the projection of bolts, cables, etc. The Committee has agreed to review the body of work to be returned to the Modeling Task Force for further evaluation. Number Eligible to Vote: 27 ________________________________________________________________ Ballot Results: Affirmative: 22 Negative: 1 780-9 Log #11 Final Action: Reject Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP ( 3.9.3 ) Explanation of Negative: ________________________________________________________________ DALESSANDRO: ERICO restates its position that the committee statement Submitter: Michael K. Toney, Equistar Chemcial following the ROP meeting incorrectly reflects the reason for ERICOs Comment on Proposal No: 780-11 decision to withdraw their proposal. Recommendation: Remove - "Permenant metal handrails and ladders that are ERICO believes the committee action taken at the ROC meeting to reject electrically continous shall be permitted to be substituted for main conductors its proposed clarification to the ROP committee statement as recorded, is where the minimum thickness is 1.63 mm (0.064 in)" incorrect. Substantiation: The explanation of negative comments give much cause for concern and they should be resolved before handrails and ladders are accepted as a conductor in place of the main conductor. Another issue that should be investigated is the requirement for bonding jumpers around mechanical joints -- would they be required.

780-3

Report on Comments -- Copyright, NFPA

Committee Meeting Action: Reject Committee Statement: See Committee Action and Statement on 780-8 (Log #3). Number Eligible to Vote: 27 Ballot Results: Affirmative: 21 Negative: 2 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP Explanation of Negative: KLEKOWSKI: See reason provided for Negative Vote on Comment 780-8. ZIPSE: I agree with the substantiation submitted by Mitchell Gurthrie in Comment 780- (Log #3). The use of handrails can be detrimental to the safety of the structure. In addition, the connection to the handrails can pose hazards to persons using the handrail due to the projection of bolts, cable, etc. ________________________________________________________________ 780-10 Log #CC1 Final Action: Accept ( 3.13.1.2 ) ________________________________________________________________ Submitter: Technical Committee on Lightning Protection Comment on Proposal No: 780-16 Recommendation: Revise Section 3.13.1.2* to read as follows: "3.13.1.2* Multiple Ground Rods. Where multiple connected ground rods are used, the separation between any two ground rods shall be at least the sum of their lengths where practicable." Annex A.3.13.1.2 is to remain unchanged. Substantiation: The Technical Committee recognizes that there is no value in the addition of an expanatory figure. Committee Meeting Action: Accept Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP ________________________________________________________________ 780-11 Log #6 Final Action: Reject ( Figure 3.13.7.2 ) ________________________________________________________________ Submitter: Stephen Humeniuk, Warren Lightning Rod Company Comment on Proposal No: 780-15 Recommendation: Revise figures as shown belo:w:

Substantiation: Formal drawing for concept approved at previous NFPA 780 Committee meeting in Las Vegas 3-19-03, 3-20-03. Committee Meeting Action: Reject Committee Statement: The Committee notes a typo in the ROC artwork reference: "Figure 3.1.3.7.2" should be "Figure 3.13.7.2". Also, the Print line "Figure B.13.7.2" should be "Figure 3.13.7.2". See Committee Comments 780-10 (Log #CC1) and 780-12 (Log #CC2). Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP

NFPA 780

________________________________________________________________ 780-12 Log #CC2 Final Action: Accept ( 3.13.7.2 ) ________________________________________________________________ Submitter: Technical Committee on Lightning Protection Comment on Proposal No: 780-15 Recommendation: Revise Section 3.13.7.2 as follows: "3.13.7.2 Sandy Soil Conditions. Because sandy or gravelly soil conditions are characterized by high soil resistivity, multiple ground electrodes shall be used to augment the lightning grounding terminal system." Delete Figure 3.13.7.2. Renumber all subsequent figures throughout the document. Substantiation: The Technical Committee recognizes that there is no value in the addition of this explanatory figure. Committee Meeting Action: Accept Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP Comment on Affirmative: HARGER: The recommendation accepted by the committee includes the statement to "Renumber all subsequent figures throughout the document." I believe this is an error. Figure numbers should match the referenced section and should not be renumbered. _______________________________________________________________ 780-13 Log #9 Final Action: Accept in Principle ( 3.18 ) ________________________________________________________________ Submitter: Michael K. Toney, Equistar Chemcial Comment on Proposal No: 780-17a Recommendation: Keep existing text and add references as recommended in 780-17. Substantiation: The five explanations of negative on this proposal identify the problem -- no substantiation for the additional installation requirements. Proposal 780-17 by Craig M. Wellman which was Accepted in Principle and included in 780-17a is all that is needed. Committee Meeting Action: Accept in Principle Replace proposed Proposal 780-17a (Log #CP6) New Section 4.18 to read as follows: 4.18 Surge Protection. 4.18.1* General. This section provides requirements for surge protection systems installed external to the facility electrical, CATV, alarm, data, or other electrical system hardware. The requirements included within this standard are limited to permanently- installed surge protective devices (SPDs). 4.18.2* Surge Protection Requirements. 4.18.2.1 Surge protection devices shall be installed at all power service entrances. 4.18.2.2* Surge protection devices shall be installed at entrances of conductive signal, data and communication services. 4.18.2.3 Surge protection devices shall be installed at all points where an electrical or electronic system conductor leaves a structure to supply another structure if the conductors or cables are run over 30 m (100 ft) and are not buried or enclosed in grounded metal conduit or tubing. 4.18.2.4 Surge protection shall be permitted for installation at sub/branch panels and at the point-of-utilization (receptacle or signal termination; also termed supplementary protection). 4.18.2.5* Surge protection devices shall not be required where, under engineering supervision, it is determined that surge threat is negligible or the lines are equivalently protected or where installation compromises safety. 4.18.3 Surge Threat Levels. 4.18.3.1* Electrical Power Circuits. The SPD shall protect against a surge produced by a 1.2/50, 8/20 combination waveform generator. SPDs shall function at their rated maximum discharge current (Imax) without failure. SPDs at the service entrance shall have an Imax rating of at least 40kA 8/20 per phase. 4.18.3.2 Signal, Data and Communication Protection. SPDs shall be listed for the protection of signal, data and communications systems and shall have an Imax rating of at least 10kA 8/20 or greater when installed at the entrance.

Figure 3.1.3.7.2

780-4

Report on Comments -- Copyright, NFPA

NFPA 780

Figure 3.13.7.2 780-11 (Log #6)

780-5

Report on Comments -- Copyright, NFPA

4.18.4* SPDs Measured Limiting Voltage. Where a SPD has been listed as a Transient Voltage Surge Suppressor, the declared suppressed voltage rating (SVR) for each mode of protection shall be selected to be no greater than those given in Table 4.18.4 for the different power distribution systems to which they may be connected. 4.18.5* Facility AC Surge Protection. 4.18.5.1 The short circuit current rating of the SPD shall be coordinated with the available fault current rating of the supply (panel) to which it is connected in accordance with NFPA 70, National Electrical Code. 4.18.5.2 The maximum continuous operating voltage (MCOV) of the SPD shall be selected to ensure that it is greater than the upper tolerance of the utility power system to which it is connected. 4.18.5.3 The SPD shall be listed for the protection of service entrances. 4.18.5.4 SPDs at grounded service entrances shall be wired in a line-toground (L-G) or line-to-neutral (L-N) configuration. 4.18.5.4.1 Additional modes, line-to-line (L-L), or neutral-to-ground (N-G) shall be permitted at the service entrance. 4.18.5.4.2 For services without a neutral, SPD elements shall be connected line-to-ground (L-G). Additional line-to-line (L-L) connections shall also be permitted. 4.18.6 Signal, Data and Communications Surge Protection. 4.18.6.1* Surge protection devices shall be provided for all signal, data and communication lines at facility entrances. 4.18.6.2 SPDs shall be selected taking into consideration aspects such as the frequency, bandwidth and voltage of the signal, data or other telecommunication lines; and ensuring the insertion losses (attenuation) introduced by the SPD(s) are within acceptable operational limits. 4.18.6.3 SPDs protecting signal, data and communications systems shall be grounded. 4.18.6.3.1 The SPD shall also be bonded to the point of grounding of the electrical service. 4.18.6.3.2 If this point is greater than 6 m (20 ft) away, a supplementary earth electrode or electrode system shall be installed at the SPD location. 4.18.6.3.3 Where provided, a supplementary earth electrode, or electrode system, shall be electrically bonded to the facilitys main ground electrode system in compliance with the NFPA 70, National Electrical Code. 4.18.6.3.4 SPDs shall not be grounded through a down conductor of the lightning protection system. 4.18.6.3.5* SPDs for data and signal line protection shall provide common mode protection. 4.18.7 Installation. 4.18.7.1 Installation of surge suppression hardware shall conform to the requirements of NFPA 70, National Electrical Code. 4.18.7.2* SPDs shall be located and installed so as to minimize lead length. Interconnecting leads shall be routed so as to avoid sharp bends or kinks. 4.18.7.3 The SPD grounding conductor shall be installed in accordance with the manufacturers instructions. 4.18.7.4* All SPD components shall be accessible for inspection and maintenance. 4.18.8* Earth Grounding Electrode. Resistance of the earth electrode system used in the grounding of surge protective devices shall comply with NFPA 70, National Electrical Code. Table 4.18.4 Maximum allowed Suppressed Voltage Ratings per mode of protection provided for different power distribution systems to which the SPD may be connected Power Distribution Line-toLine-to- NeutralLine-toSystem Neutral Ground toLine Ground 120 2W + Gnd 500 500 500 240 2W + Gnd 1000 1000 1000 120/240 3W + Gnd 500 500 500 1000 120/208 WYE 4W 500 500 500 1000 + Gnd 277/480 WYE 4W 1000 1000 1000 1500 + Gnd 277/480 WYE 4W + 1500 HRG 347/600 WYE 4W 1500 1500 1500 2000 + Gnd 240 DELTA 3W 1000 (ungrounded) 480 DELTA 3W 1500 (ungrounded) 240 DELTA 3W + 1000 1000 Gnd (corner grounded) 480 DELTA 3W + 1500 1500 Gnd (corner grounded)

Add the following to Annex A: A.4.18.1 Surge protection alone is not intended to prevent or limit physical damage from a direct lightning strike to a facility or structure. Rather, it is intended to defend against indirect lightning effects imposed upon the electrical services to a structure as part of a coordinated lightning protection system installed in accordance with the requirements of this standard. Surge currents and their corresponding overvoltage transients can be coupled onto electrical utility feeders in a number of ways. These mechanisms include magnetic or capacitive coupling of a nearby strike, or the more dramatic but much less frequent, conductive coupling of a direct cloud-to-ground discharge. These overvoltage transients pose a significant threat to modern electrical and electronic equipment. A.4.18.2 The SPD responds to surges by lowering its internal impedance so as to divert surge current to limit the voltage to its protective level; the measured limiting voltage. After the occurrence of surges, the SPD recovers to a high-impedance state line-to-ground and extinguishes current to ground through the device when line voltage returns to normal. The SPD achieves these functions under normal service conditions. The normal service conditions are specified by the frequency of the system, voltage, load current, altitude (i.e. air pressure), humidity and ambient air temperature. A.4.18.2.2 Antennas are considered a part of conductive signal, data and communication services. A.4.18.2.5 Most services to facilities will require discrete surge suppression devices installed to protect against damaging surges. Occasionally, services will be located in an area or manner where the threat from lightning induced surges and overvoltage transients may be negligible. For example, the requirements in 4.18.2.3 (also see A.4.18.6.1) exempt services less than 30m (100 ft) in length which are run in grounded metal conduit between buildings from requiring surge protection. These are examples of acceptable exceptions where SPDs may not be required on each service entrance. The standard recognizes that there may be acceptable exceptions and consequently allows for such exceptions to the requirements for surge suppression on electrical utility, data and other signal lines; provided a competent engineering authority has determined that the threat is negligible or that the system is protected in a manner equivalent to surge suppression. Allowance for the exemption of surge suppression at specific locations in this standard is not intended as a means to provide a broad exemption simply because surge suppression may be considered inconvenient to install. Rather, it recognizes that all possible circumstances and configurations, particularly those in specialized industries, cannot be covered by this standard. Determinations made by engineering authority for exempting installation of SPDs should focus on the likelihood of lightning activity in the region, the level of damage that may be incurred, and the potential loss to human life or essential services due to inadequate overvoltage protection. Three methods of analysis are commonly used for this determination, although other equivalent analysis can be used. The three are: lightning flash density/risk analysis, plant/facility statistical or maintenance records and lightning electromagnetic environmental analysis. The lightning flash density/risk analysis is an analysis to determine the frequency of lightning activity in the geographic area of the facility. As a rule of thumb, if the flash density exceeds one flash per square kilometer per year, surge suppression or other physical protection should be considered. Lightning energy can indirectly couple to services at ranges greater than one kilometer, to create potentially damaging overvoltages. Plant/facility statistical or maintenance records can also be used as a risk analysis. If these records can demonstrate the lack of damage on a service due to surges, it can be used to justify low risk of surge damage to a particular system or facility. Lastly, the lightning electromagnetic environment analysis starts with a threat electromagnetic field from a nearby lightning strike and computes the magnitude and rise-time characteristics of transients coupled into services feeding a structure or facility. Based on the computed threat, SPDs can be sized appropriately or omitted, as warranted. This analysis is typically performed for critical communications facilities and in military applications. Electromagnetic environments for such an analysis can be found in MIL-STD464, Interface Standard Electromagnetic Environmental Effects Requirements for Systems and IEC 62305-4, Protection Against lightning - Part 4: Electrical and Electronic Systems Within Structures. In all cases, the criticality of continued operation, potential life hazard to personnel and essential services, and the consequence of facility damage or shutdown should be factors in the analysis. If a hazardous condition results from a surge causing temporary shutdown without permanent damage (for example through the disabling of a computer or communication system), then the requirements for surge suppression as articulated by section 4.18 should not be exempted.

NFPA 780

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Report on Comments -- Copyright, NFPA

A.4.18.3.1 SPDs are typically sized significantly greater than the expected challenge level. At service entries, it is generally agreed that a maximum discharge current (Imax) between 40kA - 60kA will provide adequate protection. However, larger ratings that protect against less probable, but more powerful lightning events, will usually provide a better capability to handle multiple strikes and will usually provide a longer service life. Rating the SPDs Imax higher than the minimums in this document is recommended in areas with frequent lightning. Where installed, SPDs at branch panels or subpanels, should have an Imax rating of 20kA 8/20 or greater per phase. Where installed, supplementary protection (also called point-of-utilization) SPDs should have an Imax rating of 10kA 8/20 or greater per phase. A.4.18.4 The measured limiting voltages of the SPD should be selected to limit damage to the service or equipment protected. A.4.18.5 Modes of protection. Surges may be induced upon any line entering a structure. Where installed, branch panels over 30 m (100 ft) from the service entrance should have L-G or L-N and N-G modes of protection. Additionally, L-L protection is also permitted (although this is usually achieved by the L-N modes across two phases). L-L protection is achieved by the L-N modes across two phases. Several modes of protection are possible to minimize voltage differences between the individual conductors. a) Line to Line (L-L) protection places the SPD between the current carrying conductors in a power system. b) Line to Neutral (L-N) places the SPD between the current carrying conductors and the grounded conductor (neutral) in a power system. c) Line to Ground (L-G) places the SPD between the current carrying conductors and the grounding conductor (ground) in a power system. d) Neutral to Ground (N-G) places the SPD between the grounded conductor (neutral) and the grounding conductor (ground) in a power system. L-L, L-N and N-G modes of protection are not required at the service entrance. This is because a neutral-ground bond is implemented at the service entrance. e) Common mode is a term used in protecting telecommunications, data, etc., lines. This mode places the SPD between the signal conductor and ground. It is analogous to L-G mode in power systems. f) Differential mode is a term used in protecting telecommunications, data, etc., lines. In this mode, a SPD is placed between the individual signal lines, analogous to the L-L mode of protection in power systems. A.4.18.6.1 Surge protective devices should be placed on both ends of external signal, data and communication lines longer than 30 m (100 ft) connecting pieces of equipment or facilities, to protect against surges coupled into the wiring or caused by ground potential differences. A.4.18.6.3.5 Differential mode protection should also be provided where practicable. A.4.18.7.2 Longer, or looped, SPD ground conductors increase the impedance of the SPD ground circuit. The ability of the SPD to discharge current to ground is affected by this impedance. Consequently, it is essential to minimize impedance in this circuit. A.4.18.7.4 Some SPD units are provided with a failure indicator. This feature is recommended since it facilitates maintenance or test procedures. Where used, this indicator should be visible. Building maintenance should consider periodic inspection or test of SPDs. A.4.18.8 The SPD earth ground resistance is part of the total impedance of the SPD ground circuit. The ability of the SPD to discharge current to ground is affected by this impedance. Also, a lower ground resistance will minimize voltage differences of conductors attached to SPDs near the service entrance and reduce the chance of arcing or insulation breach. Consequently, it is essential to minimize impedance in this circuit. Add following definitions to Section 3.3: Combination Waveform Generator* A surge generator with a 2 ohm internal impedance producing a 1.2/50 s open circuit voltage and an 8/20 short circuit current waveshape. Measured Limiting Voltage (MLV) Maximum magnitude of voltage that is measured across the terminals of the Surge Protective Device (SPD) during the application of impulses of specified waveshape and amplitude. Maximum Continuous Operating Voltage (MCOV) The maximum designated rms value of the power frequency voltage that may be continuously applied to the mode of protection of a TVSS. Nominal System Voltage The nominal voltage (rms) of the power frequency supply. Maximum Discharge Current (Imax) The maximum instantaneous value of the current through the SPD having an 8/20 waveshape (per mode of protection). Normal Operating Voltage The normal ac power frequency voltage rating, as specified by the manufacturer, to which the SPD may be connected. Suppressed Voltage Rating (SVR)* A specific measured limiting voltage rating assigned to a Transient Voltage Surge Suppressor (TVSS). Surge A transient wave of current, potential or power in an electric circuit. Surges do not include longer duration temporary overvoltages (TOV) consisting of an increase in the power frequency voltage for several cycles. Surge Protective Device (SPD) A device composed of any combination of linear or nonlinear circuit elements intended for limiting surge voltages on equipment by diverting or limiting surge current.

Transient A subcycle disturbance in the ac waveform that is evidenced by a sharp, brief discontinuity of the waveform. It may be of either polarity and may be additive to, or subtractive from, the nominal waveform. Transient Voltage Surge Suppressor (TVSS) A surge protective device listed for connection on the load side of the main overcurrent protection in circuits not exceeding 600 volts rms. Add the following to Annex A: Combination Waveform Generator. For the open circuit waveform, the front time = 1.67(t90 - t30); where t90 and t30 are times to the 90 percent and the 30 percent amplitude points on leading edge of the waveform. The duration of this waveform will be the time between virtual origin and time to the 50 percent point on the tail. (Virtual origin is the intersection of the line connecting t90 and t30 with V=0.). For the short circuit waveform, the front time = 1.25(t90 - t10) where t90 and t10 are times to the 90 percent and the 10 percent amplitude points on leading edge of the waveform. The duration will be the time between virtual origin and time to 50 percent point on the tail. (Virtual origin is the intersection of the line connecting t90 and t10 with I=0.). Suppressed Voltage Rating (SVR) A rating (or ratings) selected by the manufacturer based on the measured limiting voltage determined during the transient-voltage surge suppression test specified in UL 1449. This rating is the maximum voltage developed when the SPD is exposed to a 500 A, 8/20 current limited waveform through the device. It is a specific measured limiting voltage rating assigned to a TVSS by testing done in accordance with UL 1449, Transient Voltage Surge Suppressors. Nominal SVR values include: 330V, 400V, 500V, 600V, 700V, etc. Add to Chapter 2 as follows: NFPA 70 National Electrical Code UL 1449 Standard for Transient Voltage Surge Suppressors Second Edition Add to Annex N as follows: NEMA LS-1, Low Voltage Surge Protective Devices IEC 62305-4, Protection Against Lightning - Part 4: Electrical and Electronic Systems Within Structures IEC 61643-12, Surge Protective Devices Connected To Low-Voltage Power Distribution Systems - Selection And Application Principles ANSI/IEEE C62.41.1 Recommended Practice on Surge Voltages in Low Voltage AC Power Circuits ANSI/IEEE C62.41.2 Recommended Practice on Characterization of Surges in Low Voltage (1000V & less) AC Power Circuits ANSI/IEEE C62.45 IEEE Guide on Surge Testing for Equipment Connected to Low-Voltage AC Power Circuits ANSI/IEEE 1100 Recommended Practice for Powering and Grounding Electronic Equipment (Emerald Book) MIL-STD-464, Interface Standard Electromagnetic Environmental Effects Requirements for Systems UL 452 Antenna Discharge Units UL 497 Protectors for Paired Conductor Communications Circuits UL 497A Secondary Protectors for Communications Circuits UL 497B Protectors for Data Communications and Fire Alarm Circuits UL 497C Protectors for Coaxial Communications Circuits Committee Statement: The Committee incorporated all of the proposed Proposal 780-17a (Log #CP6) into the new text. These changes address the submitters concerns. Number Eligible to Vote: 27 Ballot Results: Affirmative: 22 Negative: 1 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP Explanation of Negative: PORTFLEET: The uncompromising decision to include GP6 as mandatory in the main body of NFPA 780, rather than in the annex, is dysfunctional for primary users. The typical lightning protection provider/contractor will be mandated to supply a sophisticated level of multilayered surge protection under guidelines lacking the support and consensure of primary users. A much preferred option would be to include CP6 in the annex which would encourage further discussion, facilitate a more representative consensus, and provide a realistic learning curve for primary users. The annex location would also compliment the majority disposition which is that CP6 should be ultimately included as part of NFPA 70, National Electrical Code. Comment on Affirmative: GUTHRIE: I concur with the committee action with the following comments: (1) In 4.18.6.3.4, the term "down conductor" should be replaced with "main conductor". The term "down conductor" is not defined in the document and this could lead to possible confusion in interpretation of the application of the requirement. "Main conductor" is defined and more accurately reflects the intent of the requirement. (2) It may be of benefit to installers, designers, and inspectors to provide source information for the requirements specified in proposed 4.18.6.3. This will also serve to eliminate any confusion as to the applicability of the requirements in NFPA 780 versus those provided in the National Electric Code. It is recommended that the following text be added to Annex A. "A.4.18.6.3 - The grounding requirements for SPDs protecting signal, data and communications systems is in accordance with NFPA 70, Article 800.40. Where there is interpreted to be a perceived conflict between the requirements in NFPA 780 and the requirements of the National Electrical Code, the

NFPA 780

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National Electrical Code should take precedence." (3) In 4.18.6.3.3, delete "the" before NFPA 70. HARGER: It is important to stress as stated in 4.18.6.3.4 and the NEC that SPDs are not to be grounded directly to lightning protection system main conductors. Electrical construction specifications are written that allow (sometimes require) this method of grounding and the practice can be found in industry. It should be noted, however, that while a direct connection is not allowed, there will be equipotential bonding connections required between the lightning protection system conductors and the electric service ground and/or the supplementary earth electrode, or electrode system (4.18.6.3.3) to comply with the Potential Equalization requirements of 4.20. This will be at (or near) roof level for tall structures and may also occur at intermediate levels for high-rise structures. KLEKOWSKI: I applaud the Chairmans efforts to reach consensus on Proposal 780-17a and related Proposal 780-17. RUSSELL: We believe that Annex information will clarify the grounding requirements stated in 4.18.6.3.4, as follows: Surge Protection Device (SPD) grounding must comply with the provisions of the National Electrical Code (NEC), NFPA 70. The NEC prohibits grounding a SPD to a lightning protection system conductor or component. Refer to NEC Article 800.40 for methods for grounding a SPD. TOBIAS: 1) Discussion with the lightning protection installation community has revealed the desire for clarification for item 4.18.6.3.4. This paragraph was inserted to ensure explicit compliance and coordination with National Electrical Code. Consequently, I am recommending the following addition to the annex: "A.4.18.6.3.4 Grounding a SPD to a lightning protection system conductor or component is prohibited by National Electrical Code (NEC). Correct methods for grounding SPDs (specifically those installed on Signal, Data and Communications lines) are given in NEC Article 800.40. Any SPD grounding must comply with NEC. Grounding the SPD to a lightning protection conductor could present a high voltage, compared to the line voltage, on the ground terminal of the SPD. This situation may force the SPD to operate in a reverse mode, allowing unwanted surges into the protected line and the equipment grounding system of the facility electrical system, as well as damage the SPD." 2) (Also see supplemental ballot on 780-13) I concur with the supplemental ballot but note two typos in the table. The value of "1000" in the sixth row, second column should be deleted as L-N surge suppression is not effective on high-resistance grounded systems. The last row, first column should read "480 DELTA 3W + GND (corner grounded)." ________________________________________________________________ 780-14 Log #13 Final Action: Reject ( 3.18 ) ________________________________________________________________ Submitter: Paul S. Hamer, Chevron Texaco Energy Research and Technology Company Comment on Proposal No: 780-17 Recommendation: This proposal, as stated with changes required per the NFPA Style Manual, should be accepted on its own merits and Proposal 78017a should be rejected. Substantiation: A note pointing the user to the applicable reference material is needed. The information of Proposal 780-17a is incomplete and is not appropriate to add as a requirement. Committee Meeting Action: Reject Committee Statement: See Committee Action and Statement on 780-13 (Log #9). Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP ________________________________________________________________ 780-15 Log #14 Final Action: Reject ( 3.18 ) ________________________________________________________________ Submitter: Paul S. Hamer, Chevron Texaco Energy Research and Technology Company Comment on Proposal No: 780-17a Recommendation: Reject the additions of this proposal. Substantiation: By adopting the explanatory note of 780-17, the additional text is not needed. The text proposed in 780-17a is technically incomplete and inadequate to be included as a requirement in the NFPA 780 standard. Committee Meeting Action: Reject Committee Statement: See Committee Action and Statement on 780-13 (Log #9). Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP

________________________________________________________________ 780-16 Log #CC10 Final Action: Accept ( Table 4.1.1.1(A) ) ________________________________________________________________ Submitter: Technical Committee on Lightning Protection Comment on Proposal No: 780-5 Recommendation: Delete the fourth row in Table 4.1.1.1(A) in the NFPA 780 "Draft" document pertaining to "Main conductor, solid strip." Note that this pertains to the the row with "Thickness" and "Width" in the "Parameter" column. Substantiation: The Technical Committee notes that in the NFPA 780 "Draft" document, "Main conductor, solid strip" with "Thickness" and "Width" parameters was not deleted. Committee Meeting Action: Accept Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP ________________________________________________________________ 780-17 Log #CC9 Final Action: Accept ( 4.5 ) ________________________________________________________________ Submitter: Technical Committee on Lightning Protection Comment on Proposal No: 780-1 Recommendation: Change Section 4.5 in the NFPA 780 "Draft" document to read as follows: "4.5 Use of Aluminum. Aluminum systems shall be installed in accordance with other applicable sections and 4.5.1 through 4.5.4" Substantiation: The Technical Committee notes that in the NFPA 780 "Draft" document, the intent of Section 4.5 has changed. The Technical Committee clarified the the intent of the section. Committee Meeting Action: Accept Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP ________________________________________________________________ 780-18 Log #12 Final Action: Accept ( 5.3 ) ________________________________________________________________ Submitter: Michael K. Toney, Equistar Chemcial Comment on Proposal No: 780-18 Recommendation: Accept titanium. Substantiation: Mr Kaiser has provided the detailed substantiation in his explanation of his negative vote. Committee Meeting Action: Accept In Section 5.3, add "titanium" between "stainless steel," and "or". Committee Statement: The Committee accepts "titanium" as a strike termination device material. Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP

NFPA 780

________________________________________________________________ 780-19 Log #5 Final Action: Accept in Principle ( Annexes A through N ) ________________________________________________________________ Submitter: Mitchell Guthrie, Universal Systems, Inc. Comment on Proposal No: 780-25 Recommendation: Revise order of Annexes as follows: Annex A - Explanatory Material Annex B - Principles of Lightning Protection Annex C - Explanation of Bonding Principles Annex D - Inspection and Maintenance of Lightning Protection Systems Annex E - Ground Measurement Techniques Annex F - Protection for Trees Annex G - Protection for Picnic Grounds, Playgrounds, ... Annex H - Protection for Livestock in Fields Annex I - Protection for Parked Aircraft Annex J - Protection for Electronic Facilities Annex K - Protection for Structures Housing Explosives Materials Annex L - Risk Assessment Guide Annex M - Guide for Personal Safety Annex N - Referenced Publications Substantiation: I concur with the proposal to rearrange the annexes so they are in a logical sequence, but there is some benefit to renumbering (moving) as few as necessary. New annex reference numbers could cause confusion for longtime users of the document, some confusion as to the subject of the annex if only the annex letter is given (i.e. Annex C of 780-2000 would be Guide for Personal Safety but it would be Explanation of Bonding Principles in 7802004), and would require revision of any documents referencing the annexes (such as military documents referencing Annex K, etc.). The amount of change should be kept to a minimum where practicable.

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The proposed revision will allow the annex "number" for Trees (Annex F) and Explosives (Annex K) to remain the same and save some principle users of the document the problem of revising their documents while at the same time meeting the intent of the revision. Committee Meeting Action: Accept in Principle Revise order of annexes as follows: Annex A - Explanatory Material Annex B - Principles of Lightning Protection Annex C - Explanation of Bonding Principles Annex D - Inspection and Maintenance of Lightning Protection Systems Annex E - Ground Measurement Techniques Annex F - Protection for Trees Annex G - Protection for Picnic Grounds, Playgrounds, Ball Parks, and Other Open Places Annex H - Protection for Livestock in Fields Annex I - Protection for Parked Aircraft Annex J - Protection for Electronic Facilities (or reserved) Annex K - Protection of Structures Housing Explosives Materials Annex L - Lightning Risk Assessment Annex M - Guide for Personal Safety from Lightning Annex N - Informational References Committee Statement: The Committee agrees with the submitter. Because of the use of this standard by various agencies (ie., military, etc.), it is essential that Annex K (Protection of Structures Housing Explosives Materials) remain lettered as Annex K. Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP Comment on Affirmative: TOBIAS: Annex I should read "Reserved" as the committee intent is to hold the proposed Annex I.

or where extremely sensitive operations warrant this level of protection. The optimum protection for structures housing explosives would be to enclose the object to be protected within an earthed perfect conducting continuous shield of adequate thickness, and by providing adequate bonding of the services entering the structure at the entrance point into the shield. This would prevent the penetration of lightning current and related electromagnetic field into the object to be protected and prevent dangerous thermal and electrodynamic effects of current, as well as dangerous sparking and overvoltages for electrical and electronic systems. Effective lightning protection is similarly provided by metallic structures such as those formed by the steel arch or the reinforcing steel in the walls and floors of earth-covered magazines if the steel reinforcement is bonded together and it meets the minimum ground system resistance recommendations of Section K.4. Substantiation: The proposal is out of place and unnecessarily restrictive. K.3 deals with "Type of System" yet ROP 780-36 goes into great detail on the construction of a true Faraday cage versus a type of air termination system (as per the other subsections). The proper revision to this section would be to change the title of K.3.4 to "Metallic Structures" (or possibly "Mesh-type Systems"). Any existing discussion relative to a Faraday cage should be moved to K.2 where the term is introduced. This proposal goes above and beyond what is currently required in existing military documents and would be justified in less than 2 percent (conservative estimate) of all cases where the construction of the structure is currently allowed to serve as the air termination and down conductor subsystems; which is the obvious intent of existing K.3.4. There is no justification provided that would suggest why this annex should be more restrictive than applicable military and draft international documents on the subject and justify why the use of properly grounded all metallic structures of >3/16 in. steel would no longer be acceptable for those applications where the contents of the structure is not susceptible to radiated LEMP. Committee Meeting Action: Accept in Principle Change Section K.3.4 to read as follows: "K.3.4 Metallic Cage. The optimum protection for structures housing ________________________________________________________________ explosives would be to enclose the object to be protected within a grounded 780-20 Log #1 Final Action: Hold continuously conductive enclosure of adequate thickness, and by providing ( Annex I ) adequate bonding of the services entering the structure at the entrance ________________________________________________________________ point. This would prevent the penetration of lightning current and related Submitter: Mitchell Guthrie, Universal Systems, Inc. electromagnetic field into the object to be protected and prevent dangerous Comment on Proposal No: 780-33 thermal and electrodynamic effects of current as well as dangerous sparking Recommendation: Delete the proposed annex and return the document to a and overvoltages for electrical and electronic systems. task force for additional development. "Effective lightning protection is similarly provided by metallic structures Substantiation: The proposal is not currently mature enough for publication such as those formed by the steel arch or the reinforcing steel in the walls and as an annex to the document and should be returned to a task force for further floors of earth-covered magazines if the steel reinforcement is bonded together development. and it meets the minimum ground system resistance recommendations of Committee Meeting Action: Hold Section K.4." Committee Statement: This comment was held because it would propose Also, in Section K.4.2, replace "Faraday cage" with "metallic cage". something that could not be properly handled within the time frame for Delete text for new Section K.7.5 Faraday Cage System Inspection [780-38 processing the Report on Comments. A Committee task group is to be assigned (Log #CP13)]. to review this annex development. Committee Statement: The Committee agrees with the submitter that Number Eligible to Vote: 27 the term "Faraday Cage," per NFPA 780-2000, is not technically correct. Ballot Results: Affirmative: 23 Rewording Section K.3.4 provides the intended clarification. Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP The Committee also agrees with the submitter to delete new Section K.7.5 Comment on Affirmative: Faraday Cage System Inspection [780-38 (Log #CP13)]. GUTHRIE: I concur with the action to Hold the comment based on the Number Eligible to Vote: 27 understanding that the result of the action is that the proposed ROP 780-33 will Ballot Results: Affirmative: 22 Abstain: 1 not be published in the 2004 Edition of NFPA 780. Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP Explanation of Abstention: ________________________________________________________________ LANZONI: We object to the use of the word "optimum" in the phrase "The 780-21 Log #CC6 Final Action: Accept optimum protection for structures housing explosives...". This wording is too ( K.1.1 ) exclusive and does not allow for cost considerations, possible bound charge ________________________________________________________________ reactions, alternate technologies, etc. Submitter: Technical Committee on Lightning Protection We suggest an alternative phrase such as, "An effective protection methods Comment on Proposal No: 780-31 for structures housing explosives..." Recommendation: In Section K.1.1 of the NFPA 780 "Draft" document, change "Lighting protection systems for open shelters ..." to "Lightning ________________________________________________________________ protection systems for open shelters ..." 780-23 Log #2 Final Action: Accept Substantiation: The Technical Committee corrects the spelling of the word ( Appendix M ) "lightning" in Section K.1.1 of the NFPA 780 "Draft" document. ________________________________________________________________ Committee Meeting Action: Accept Submitter: Mitchell Guthrie, Universal Systems, Inc. Number Eligible to Vote: 27 Comment on Proposal No: 780-39 Ballot Results: Affirmative: 23 Recommendation: Update the references to AFR 127-100 and DoD 6055.9Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP STD as follows: AFR 127-100, Explosive Safety Standards, Dept. of Air Force, Washington, ________________________________________________________________ D.C. May 1983 780-22 Log #4 Final Action: Accept in Principle DoD 6055.9-STD, Ammunition and Explosives Safety Standards, Chapter 7, ( K.3.4 ) Department of Defense, October 1992 July 1999. ________________________________________________________________ AFMAN 91-201, Explosive Safety Standards, Department of Air Force, Submitter: Mitchell Guthrie, Universal Systems, Inc. Washington, DC, October 2001. Comment on Proposal No: 780-36 Substantiation: AFR 127-100 has been replaced by AFMAN 91-201 and DoD Recommendation: Delete proposal in its entirety and revise K.3.4 as follows 6055.9-STD has been revised. (also requiring the deletion of the proposed text for new K.7.5). Committee Meeting Action: Accept K.3.4 Metallic Structures Faraday Cage. The optimum scheme for protecting Number Eligible to Vote: 27 extremely sensitive operations from all forms of electromagnetic radiation is to Ballot Results: Affirmative: 23 enclose the operation(s) or facility inside a Faraday cage. A true Faraday cage Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP is difficult to construct and is economically justified only for critical facilities

NFPA 780

780-9

Report on Comments -- Copyright, NFPA

________________________________________________________________ 780-24 Log #10 Final Action: Accept in Part ( Annex M ) ________________________________________________________________ Submitter: Michael K. Toney, Equistar Chemcial / Rep. American Chemistry Councl Comment on Proposal No: 780-39 Recommendation: Include the reference to the Tobias Paper from the 2003 PCIC. Include the reference to IEEE 141-1997. Substantiation: The Tobias Paper is now published in the 2003 PCIC Technical Conference Record of Conference Papers Cat# 03CH37485. IEEE 141-1997 is the latest edition of IEEE 141 and chapter 6 is an extensive treatment of surge protection and therefore does have relevance to NFPA 780. Committee Meeting Action: Accept in Part Add the following to Annex M: "IEEE Std 141-1997, IEEE Recommended Practice for Electric Power Distribution for Industrial Plants, 1997." Committee Statement: The Committee has reviewed the two documents referenced by the submitter. The Committee accepts the second part presented by the submitter. The Committee agrees that IEEE Std 141-1997 is relevant. The Petroleum and Chemical Industry Conference (PCIP) paper provides no significant additional information to the use of this standard beyond Tobias, J. M., ed., The Basis of Conventional Lightning Protection Technology, Federal Interagency Lightning Protection Group, available on www.stinet.dtic.mil, Report #ADA396784, p.21, June 2001, that is already referenced. Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP

________________________________________________________________ 780-25 Log #15 Final Action: Reject ( Annex M ) ________________________________________________________________ Submitter: Paul S. Hamer, Chevron Texaco Energy Research and Technology Company Comment on Proposal No: 780-39 Recommendation: Include the second paper cited in the proposal. Include IEEE Std 141-1993. Substantiation: Include the second paper cited, since it has been published in the 2003 IEEE PCIC Conference Record (September 2003). Include IEEE Std 141-1993, since Chapter 6 (Surge Voltage Protection) and Chapter 7 (Grounding) are directly relevant to lightning protection. Committee Meeting Action: Reject Committee Statement: See Committee Action and Statement on 780-24 (Log #10). The Committee agrees that IEEE Std 141-1997 is relevant, while 141-1993 is not. Number Eligible to Vote: 27 Ballot Results: Affirmative: 23 Vote Not Returned: 4 FREDLUND, HEARY, MELTON, RAPP

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780-10

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