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Copyright © 2010 American Institute of Chemical Engineers (AIChE)

Safety

Create Effective Process Safety Moments

Deborah Luper NANA Worley Parsons

Process safety topics are underrepresented in safety communications. Here are ideas on how to convey your organization's safety priorities in messages tailored to the audience.

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ost companies recognize the value that a strong safety ethic brings to business, and many organizations begin business meetings with a brief "safety moment" or use monthly safety meetings to reinforce management's commitment to safety. These messages generally focus on personal safety -- often to the exclusion of process safety, which deserves more emphasis than it typically gets. Many individuals who are responsible for conducting a safety meeting or preparing a safety moment struggle to find new, interesting and pertinent topics. It can be a challenge to provide safety messages that are relevant and applicable, that target a site's most pressing issues, and that inspire people to take action -- especially in facilities that remain fundamentally the same year after year. Introducing process safety topics can expand the breadth and depth of safety messages as well as provide emphasis on the importance of process safety.

Additional CCPS Resources

"A Practical Approach to Hazard Identification for Operations and Maintenance Workers" is a new publication from the Center for Chemical Process Safety (CCPS) that provides extensive step-by-step instructions on how to recognize a broad range of hazards and how to take appropriate steps to correct them before they become disasters. CCPS is also preparing Process Safety Moment presentations, with slides and an accompanying script, that can be tailored for any audience. The first CCPS Process Safety Moment will be available this fall. For updates, check the Beacon website, www.aiche.org/beacon.

Differentiating personal and process safety Safety messages can be divided into three categories: personal safety on the job, personal safety off the job, and process safety. Although all three areas are important, the relative importance of each varies by business and work location. Personal safety on and off the job is relevant to all businesses and all types of employees, from the operator or process engineer at a chemical plant or refinery to the administrative assistant in the corporate office. Each employee has the ability to take action to improve his or her own personal safety, and often that of coworkers. Personal on-the-job safety topics include: reducing slips, trips and falls; using ladders and power tools correctly; and wearing appropriate personal protective equipment. Personal off-the-job safety topics include: driving safety, proper nutrition, prevention of house fires, and accidents associated with sports and hobbies. A company's personal safety performance is important because it affects medical and liability insurance costs, productivity due to lost work time, the ability to get and keep work, and the business's reputation with the public. Process safety is relevant primarily to the process industries and businesses that support them. Process safety topics include safe operating limits, overpressure scenarios and relief paths, and failure mechanisms and safeguards. The chemical industry has become increasingly aware of the profound effects that catastrophic industrial accidents arising from process upsets have on a business's reputation, the monetary and nonmonetary costs due to facility damage and lost production, and the impact of regulatory citations and fines. Therefore, it is essential to emphasize process safety messages.

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The CCPS Process Safety Beacon Illustrates Common Failures Storage Tanks Tank collapse due to the creation of an internal vacuum ­ Feb. 2002 Overpressure due to the addition of excess heat ­ Apr. 2005 Overfilled tanks ­ Sept. 2006, Sept. 2009, Oct. 2009 Tank collapse due to a vent being plugged with a plastic sheet ­ Feb. 2007 Large ( > 1 million gal) tank failure and resulting flood ­ May 2007 Automatic shutoff malfunction ­ Mar. 2008 Fire due to inadequate bonding, grounding and/or filling ­ Dec. 2008, Jan. 2009, Feb. 2009 Maintenance Work Corrosion and/or erosion ­ Feb. 2005, Jan. 2010 Massive fire/damage from carelessness with oily rags ­ May 2005 Lock-out/tag-out mistakes ­ June 2005 Lack of process isolation (and/or communication) during maintenance ­ July 2005 Unauthorized cylinder modification and resulting overpressurization ­ Dec. 2006 Temporary shelter becoming a confined space ­ Aug. 2007 Pipeline nicked during construction activity ­ Apr. 2008 Infrequent Operations: Startup, Shutdown, Out-of-Service Equipment Valves providing insufficient process isolation ­ Mar. 2005 Rupture of an out-of-service line due to insufficient isolation ­ Oct. 2008 Accidents during plant and process startups ­ Dec. 2005 Compressed-Gas Cylinders Fire-suppression system cylinders ­ Feb. 2002 Compressed gas cylinder becoming a projectile ­ June 2008 Vapor Clouds Flammable gas release and fire ­ Sept. 2004 Gas leaks, and previous warning signs and near misses ­ Oct. 2005 Flammable materials stored in standard refrigerators ­ Nov. 2008 Storage Facilities Explosion and fire in a gas cylinder storage facility ­ Oct. 2006 Explosion resulting from batteries releasing hydrogen ­ May 2002 Reactive Chemicals and Incompatibilities Chemical incompatibility ­ July 2006, Mar. 2009 Transferring and/or Disposing of Chemicals Toxic reaction in a sewer ­ Aug. 2005 Hose failure during chlorine transfer ­ Aug. 2004 Bypassed/Inoperative Safety Systems Mexico City accident ­ Nov. 2009 Bhopal accident ­ Dec. 2009 Miscellaneous Dust explosion ­ May 2006 Cold embrittlement ­ Nov. 2007 Safe work locations ­ Mar. 2010 The searchable CCPS Process Safety Beacon archive is available at: www.sache.org/beacon/products.asp. The archives are readonly for nonmembers.

Know your safety priorities The chemical process industries (CPI) have become increasingly aware of the difference between process and personal safety. It is clear that emphasizing personal safety is not necessarily sufficient to avoid harm to personnel and equipment that results from process upsets or process equipment failures. Unlike personal safety, the key group of individuals that has the knowledge and influence to meaningfully affect process safety tend to be the facility and design engineers, management, and operations and maintenance personnel. Although nontechnical staff are generally less capable of making a profound impact on process safety than a process engineer or plant manager, it is important that they have a general understanding of process safety. Chemical engineers are uniquely qualified to introduce process safety to the rest of the workforce. Monthly safety meetings and meeting safety moments are prime opportunities to get the message out. When selecting a safety topic for discussion, take a moment to reflect on the safety issues that are applicable to

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your site, particularly the relevance of process safety and personal safety.

Know your audience At facilities that perform chemical processing, introducing pertinent process safety topics can enhance all employees' understanding of the process and what they can do to reduce the potential for safety incidents. Select topics that are meaningful and relevant to the workforce. Whenever possible, use examples from your own plant rather than leaving it to the audience to draw parallels between theory and its relevance to their facility. Topics should be selected and presented so that they can be understood by the audience and so that suggested actions are within their personal sphere of influence. For example, giving a presentation on what upper management can do to promote a strong safety culture to an audience of maintenance staff is unlikely to result in them taking any action, simply because they are not senior management. On the other hand, a presentation that explains how the limit switches placed on certain valves are essential to limiting

flow and ensuring that downstream pressure safety valves (PSVs) can relieve system pressure is likely to result in the maintenance staff remembering to reinstall the limit switches after performing maintenance. Presentations that illustrate a dramatic effect can be memorable, such as a tank collapsing due to cooling of a volatile chemical in a closed-loop system. A case study about an incident at a facility similar to your own can also make an impact. The case study can be used effectively as a springboard to discuss how and why a similar incident could occur at your own plant, the current safeguards that are in place to prevent it, and what more could or should be done. The "Process Safety Beacon" from the Center for Chemical Process Safety (CCPS) is a source of succinct case studies of industrial accidents that can easily be adapted for use in a safety moment. Aimed at delivering process safety messages to plant operators and other manufacturing personnel, the monthly one-page Beacon covers the breadth of process safety issues. Each edition presents a real-life incident, describes the lessons learned, and provides practical tips to prevent a similar accident. The Beacon appears each month in CEP (see p. 37) and a free e-mail subscription is available in various languages at www.aiche.org/beacon. For more in-depth discussions, case studies are also available from the U.S. Chemical

Safety and Hazard Investigation Board (www.csb.gov). It is often helpful to show how a piece of legislation or a regulation that the facility must comply with has resulted in positive outcomes that are not intuitively obvious (e.g., the reduction in ozone-depleting chemicals). Other subjects include information that enables individuals to understand the ramifications of doing routine tasks properly or that aids in making the right decisions. For example, a presentation that shows how specific pressure gages or flowmeters are used to monitor a process and avoid runaway reactions could serve as a lead-in to a discussion underscoring the importance of routinely and conscientiously calibrating instruments. A case study of a failed compressor could be used to illustrate why it is important to pay attention to and respond to the results of vibration monitoring tests. Case studies of failed pipelines can emphasize the importance of corrosion inhibitors and corrosion monitoring programs. Videos showing the results of mixing incompatible chemicals can remind operators to check and follow procedures for mixing chemicals. The following sections describe process safety topics that may be applicable to various groups of employees. Many of the topics focus on motivating individuals by explaining the potential consequences of their actions, while others focus on providing insight into how their actions fit into the big picture.

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For facility operations and maintenance staff

hen addressing operations and maintenance staff, choose topics that illustrate the importance of tasks that they normally perform and that are within their realm of influence. For example, operators might benefit from insight into high-consequence process upset conditions that even experienced operators have not encountered because of their low frequency. Other topics include: · engineering design issues, such as process upset scenarios that result in flowrates that are far greater than one would expect based on operating experience · causes and effects of potential failures that are lowprobability but high-consequence events, such as heat exchanger tube rupture or gas blow-by through a separator; site-specific examples can be identified by reviewing the pressure relief valve (PRV) sizing documentation · an overview of site-specific equipment, such as flow-limiting orifice plates that are used to reduce the size and cost of downstream pressure-relief devices · results of dispersion modeling of toxic gas releases · signs and symptoms of impending catastrophic events · the theory behind and consequences of repetitive, low-consequence events, such as steam hammer, that have the potential to lead to significant, high-consequence events, such as vibration-induced failures · unique physical and chemical properties -- especially those that would matter only in an upset condition, such as a heater failure that could result in the formation of hydrocarbon hydrates at an unexpected and inconvenient piping location · potential problems resulting from uncommon weather patterns, such as temperature extremes or high wind loads, to enable operators to react appropriately to unforeseen conditions.

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For engineering or management audiences

rocess safety is often an elusive objective for facilities because it requires an understanding of both the big picture and the minute details of implementation. In contrast, many chemical engineers are specialists. For example, process safety requires an understanding of basic theory (e.g., formation of highly hazardous byproducts under abnormal conditions), the assumptions made in the design phase (e.g., safety-related devices that limit flowrates or heat release), equipment design (e.g., relationships among operating pressure, maximum allowable working pressure (MAWP), design pressure, and hydrotest pressure), instrumentation (e.g., assumptions and expectations of safety instrumented systems), operations (e.g., atypical conditions during startup, shutdown and conditioning procedures), and maintenance (e.g., the proper gasket materials, and how to properly install a gasket). Fortunately, significant improvement in process safety can result from sharing information among disciplines or departments and encouraging employees to learn more about topics outside their primary area of responsibility. Presentations to engineering or management audiences are typically a review of standard process safety elements rather than a presentation of new ideas. They serve as reminders of the importance of established process safety practices in everyday work. Some process safety topics naturally lead into environmental issues because of the effects some process upsets have on public safety. Suggested topics include: · current flows and maximum allowable capacities for pressure-relief or waste-management systems · how to document process safety information and procedures for keeping the relevant documents up to date · changes to the process since startup and how they affect overpressure scenarios or operating and maintenance procedures · in meetings that include other engineering disciplines, discussions of mechanical engineering or instrumentation work related to the system's safety · presentations by specialists in safety instrumented systems or dynamic process modeling that provide an overview of the topic or recent innovations · presentations by operations or maintenance personnel about ongoing operations and/or maintenance problems, followed by a brainstorming session on what might be happening and what can be done about it (accidents are often foreshadowed by a chronic, ongoing, unresolved operations or maintenance problem) · discussion of piping dead legs within the facility and factors that create hazards (e.g., corrosion, abnormally cold temperatures that can result in freezing or the formation of petroleum hydrates, elevated temperatures and the resulting overpressure scenarios) · results of studies done by corporate staff or external consultants, such as a layer of protection analysis (LOPA) or facility siting study · air dispersion modeling results for potential hazardous and toxic gas releases · presentations that link water discharge limits in environmental permits with geotechnical characteristics of the site, such as underlying aquifers, soil permeability, and nearby drinking water sources or fish habitats · presentations that link the site's air emission limits with local air quality (e.g., areas of nonattainment or daily air quality ratings in the newspaper) and/or how such limits protect employees who are particularly susceptible (e.g., those with temporary respiratory ailments, such as a cold, flu, bronchitis or pneumonia, or with long-term ailments such as allergies, asthma, or emphysema, as well as those who are vulnerable as a result of personal choices such as smoking) · highlights of the dramatic improvements that early regulations have made (e.g., rivers that no longer catch fire, or reductions in acid rain) · in meetings with design engineers, a review of startup/shutdown and maintenance scenarios that result in temperatures, pressures and flow paths that differ from normal operating conditions · at meetings that include nontechnical managers, overviews that explain how a particular policy or procedure is intended to head off specific, undesirable consequences, such as case studies or video showing catastrophic failures due to corrosion in pipes or vessels. This can be a good lead-in to an overview of the elements of your own plant's corrosion control programs. Alternatively, presenting examples and/or statistics showing the prevalence of process safety incidents during startup, shutdown and nonroutine activities can segue into a discussion on the safety precautions necessary for an upcoming plant turnaround.

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For nontechnical audiences

ontechnical personnel are often interested in topics that can be applied to their own residence or home maintenance. Elements of process safety such as pressure relief and backflow prevention are incorporated into residential housing and can be interesting topics for a nontechnical audience -- especially if the presentation focuses on clear, simple actions the individual can take regardless of whether he or she understands the theory behind the action. With a little thought, the underlying process safety concepts associated with popular hobbies or sports can be identified and articulated, too. A few ideas for topics and tips include: · the concept of overpressure in home heating systems and tips on recognizing the pressure relief valve on the boiler and/or hot water heater, illustrations of fouling, and how to perform periodic inspections · a discussion of backflow prevention in household drinking water loops and related homeowner choices, such as outdoor hose connections (with or without vacuum release), locating indoor water spigots well above the high-water level of sinks and tubs, and the location of key backflow prevention devices (e.g., from the house to the public system, and from heating system to the home's potable water loop) · in locations where homeowners often undertake their own repairs, a review of how to distinguish piping and solder suitable for different systems, e.g., drinking water vs. nondrinking water, such as heating systems · an explanation of how carbon monoxide is formed from incomplete combustion and tips for comparing options for upgrading or replacing a heating system, such as the advantages of sealed combustion chambers and of isolating fired equipment from the living areas; this is particularly relevant as many homeowners consider replacing old heating systems with more energy-efficient ones · tips for improving indoor air quality, such as avoiding indoor air purifiers that generate high levels of ozone, minimizing air flow between living areas and garages (where auto exhaust and paint and solvent fumes could build up), using nonvolatile cleaning products (with an explanation of volatile vs. nonvolatile solutions), and changing air filters on forced-air furnaces · how flammable vapors, due to their density, can accumulate in unexpected places and eventually reach flammable levels, and suggestions for safely storing flammable paints, fuels and maintenance materials away from ignition sources, such as autos, gas-powered lawn mowers, boilers, and non-electric water heaters. An excellent visual aid is the February 2004 Process Safety Beacon, which describes an incident involving a gas cylinder of acetylene with a slight leak that was left in a closed vehicle and shows the damage done to the vehicle from the resulting explosion · the chemical hazards associated with household products · the reactive chemical hazards of common household chemicals, such as bleach and ammonia, which form toxic chloramines · a presentation on the inherent dangers associated with the stored energy of containerized gases found in residential settings, such as fire extinguishers, propane cylinders used for outdoor barbeques, and butane fuel cylinders for portable stoves or hand-held torches.

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Final thoughts Chemical engineers have a unique role to play in communicating the actions necessary to maintain the integrity of chemical process industry facilities. We have knowledge of factors that influence process safety -- such as the essential safeguards identified during process hazard assessments, the potential for and consequences of runaway reactions, and identities of incompatible chemicals used at the site. In order to reduce the incidence of catastrophic process-related failures, it is crucial that we develop skill at reiterating essential process safety information clearly and precisely to our colleagues in operations, maintenance, management, CEP and other engineering disciplines.

DEBORAH LUPER is a principal process engineer for NANA Worley Parsons (Box 111100, Anchorage, AK 99511-1100; Phone: (907) 273-3900; E-mail: [email protected]), where she is assigned as a process engineer at the BP gas-to-liquids demonstration plant developing a proprietary clean-energy technology. Her previous projects included high-level planning for new oilfields, incremental improvements for existing Prudhoe Bay units, and numerous environmental projects. She has worked on projects that exemplify innovation and a commitment to sustainable technology, such as developing a hydro-biodegradable plastic. She began her career in a Western Electric semiconductor processing facility and for two years volunteered in Somalia manufacturing hand-operated water pumps. She has been a member of AIChE for 30 years, serving as both director and treasurer of a local section. She earned a BS in chemical engineering from Worcester Polytechnic Institute and an MS in manufacturing systems from Clarkson Univ.

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