The History of the Halon Phaseout and Regulation ... - ACS Publications

Chapter 2

The History of the Halon Phaseout and Regulation of Halon Alternatives 1

Downloaded by UNIV MASSACHUSETTS AMHERST on October 6, 2012 | http://pubs.acs.org Publication Date: May 5, 1997 | doi: 10.1021/bk-1995-0611.ch002

Stephen O. Andersen, Karen L. Metchis , and Reva Rubenstein U.S. Environmental Protection Agency, Mail Code 6205J, 401 M Street, S.W., Washington, DC 20460

Halogenated fire agents (Halon 1301, Halon 1211 and Halon 2402) were once thought to be essential for fire safety. However, once their role as potent ozone depleters became scientifically confirmed, fire protection engineers, the military, and regulators rallied world-wide to reevaluate fire protection practices and to develop new chemical and technological solutions. Today, production of halon has ceased in the industrialized world, and less then 20 percent of former uses still require halon. These remaining uses are being served by the existing supplies of halon while research on alternatives continues. The Montreal Protocol and International Cooperation The fire protection community has been one of the most important proponents and early implementers of new technology and management to protect the stratospheric ozone layer. This introduction looks back over the last ten years to explain how public, government and industry stakeholders came together on a common and successful global agenda. Stratospheric ozone is depleted by halons and other ozone-depleting substances. Depletion of ozone allows more harmful ultraviolet radiation to reach the Earth's surface. Increases in UV-B radiation are likely to have substantial adverse effects on human health, including increases in the incidence of, and morbidity from, skin cancer, eye diseases, and infectious diseases (7). Peak global ozone depletion is expected to occur during the next several years, and the stratospheric ozone layer is expected to recover in about 50 years in response to international actions under the Montreal Protocol and its Amendments and Adjustments (2). The early phaseout of halon production produced at least 15 percent of the protection under the Montreal Protocol (3)(4). 1

Corresponding author This chapter not subject to U.S. copyright Published 1995 American Chemical Society In Halon Replacements; Miziolek, A., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1997.


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The halon production phaseout took effect January 1, 1994 with little disruption because the fire protection community had established global information networks and coordinated halon banks. Halon banks are important because environmentally acceptable alternatives have not been commercialized for some critical fire protection applications representing 15-20% of former uses (5)(6). In 1985 a small group of countries signed the Vienna Convention of Ozone Layer Protection which is the framework for negotiating the Montreal Protocol. In that document halons are only briefly mentioned in an annex on monitoring of data because earlier analysis had concluded that halon was rarely released and predicted that halon use would decline as computer systems became smaller. In 1986 few substitutes were identified for any of the ozone-depleting substances and it was widely believed that halon uses were all essential. It was hoped that chlorofluorocarbon (CFC) restrictions alone would adequately protect the ozone layer. By late 1986 the U.S. Environmental Protection Agency (EPA) began to take a new look at halon use. E P A quickly discovered that the National Fire Protection Association (NFPA) planned to mandate full discharge testing of all new Halon 1301 (CF Br) systems in order to verify that the controls and hardware properly functioned and that the concentration of halon gas was high enough and contained long enough in the enclosure to extinguish the design fire. The E P A concern was that property owners, insurance companies, and fire authorities might also conclude that older systems should be discharge tested or that all systems should be periodically discharge tested. This action alone would have substantially increased the threat to the ozone layer. Because halons were not part of any regulatory plan and because fire protection involved human life and property, E P A decided to seek cooperative and collaborative solutions. N F P A managers suggested that E P A contact Gary Taylor, Chair of their Halon 1301 Committee and partner in one of the largest North American fire protection companies. Gary Taylor had worked for DuPont during the early promotion of Halon 1301 and had designed halon systems for some of the most demanding national defense, industrial, and cultural heritage applications. In the late 1970s Mr. Taylor testified before the U.S. Congress that halon use was essential and should not be restricted. In the first meeting with EPA, Gary Taylor estimated that very little halon was used to actually fight fires but that emissions from testing, training, and accidental discharge were far higher than analysts had calculated. He proposed a plan to investigate halon use, to involve the best global experts in problem solving, and to use market incentives to change the way that engineers and property owners protected against fire risk. He advocated that the full range of stakeholders from chemical manufacturers to building designers and insurance underwriters, fire equipment manufacturers and installers, and military and civilian halon system customers be recruited to participate in developing a solution to the problem. His proposal was that E P A and the fire protection community jointly investigate halon controls with the goal of only acting by broad consensus. 3

In Halon Replacements; Miziolek, A., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1997.


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In early 1987 EPA initiated projects with the U.S. Department of Defense and U.S. Air Force. Gary Vest, then the Deputy Assistant Secretary of the A i r Force for Environment, Safety and Occupational Health, and then-Captain Edward "Tom" Morehouse of the A i r Force Engineering and Services Center, became the first of many military leaders to spearhead halon elimination efforts. By September 1987 the A i r Force was confident enough to send Captain Morehouse to Montreal to help make the case that halon should be included in the Protocol. Diplomats reasoned that if the military could reduce their use, so could the civilian sector. Without this endorsement halon production might not have been included in the 1987 Protocol. Meanwhile, analysis was documenting that less than ten percent of halon emissions were actually for fire fighting (7). E P A , N F P A , and other organizations were now working as a team to educate stakeholders on the importance of eliminating testing, training, and accidental discharges. In Australia the State of Victoria implemented strong controls on halon use and plumbers unions refused to install or service halon systems unless it was deemed essential by a committee of public and private experts. Elsewhere, authorities of jurisdiction were helping eliminate requirements for discharge testing and training with halon. In 1989 the United Nations Environment Programme (UNEP) organized the first Technology Assessment including the work of the Halon Technical Options Committee, Co-Chaired by Gary Taylor and Tom Morehouse. This Committee of international experts became the catalyst of global efforts. Slowly even more fundamental change was occurring. Property owners began to use a broader range of strategies to protect property. Computer manufacturers confirmed that, contrary to advertizing claims for halon, most equipment could be protected with water sprinklers. Insurance companies agreed to offer their most favorable rates to ensure property with protection other than halon. Telecommunication companies reduced the need for halon by using cable materials that would not burn. The military began to design weapons systems that did not depend on halon. Broader fire protection engineering considerations and fire prevention began to take precedence over the basic fire extinguishing perspective. These efforts stimulated other important paradigm shifts. For example, military aircraft designers reevaluated whether space and weight might be better allocated to threat avoidance or weapons rather than fire protection. Commercial aircraft engineers realized that water mist systems might better protect against fires and offer passengers protection from the poisonous gases of combustion. EPA and the A i r Force helped organize the Halon Alternatives Consortium to help identify the most promising research opportunities and worked to prepare markets to accept alternatives and substitutes as they developed. Marine Corps, Navy, and A i r Force cooperated to develop the first practical halon recycling equipment and were the first organizations in the world to deploy this equipment. The Navy and Marine Corps teamed up with E P A to teach halon recycling to experts form Argentina, Brazil, Chile, China, Costa Rica, Ecuador, Fiji, Guatemala, India, Malaysia, the Maldives, Mexico, Panama, the Philippines, Thailand, Trinidad and Tobago, Uruguay, and Venezuela.


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Halons are still required for 15-20% of the applications they satisfied in 1986. If halons presently contained in existing equipment were never released to the atmosphere, the integrated effective future chlorine loading above the 1980 level is predicted to be 10% less over the next 50 years (8). Thus much work remains to complete the phaseout of halon use. Chemical substitutes to halon for the remaining important uses are an important part of the ultimate solution.


U.S. Regulation of Halons and Halon Substitutes When the Montreal Protocol was signed in 1987, the Environmental Protection Agency's (EPA) role in stratospheric ozone protection derived from the Clean Air Act of 1977, Part B, section 157(b): "...theAdministrator shall propose regulations for the control of any substance, practice, process or activity (or any combination thereof) which in his judgment may reasonably be anticipated to affect the stratosphere, especially ozone in the stratosphere, if such effect in the stratosphere may reasonably be anticipated to endanger public health or welfare." This language gave EPA broad latitude but it did not give clear guidance. EPA began developing control strategies based primarily on ozone depletion potential (ODP). A product with an ODP lower than the CFCs was considered to have an advantage over the halons. Thus, FM-100 (HBFC-22B1) with an ODP of 0.74 (9) was investigated as an effective halon substitute. With the enactment of the Clean A i r Act Amendments of 1990 ( C A A A ) , Congress provided guidance to EPA by stipulating that any substance with an ODP of 0.2 or greater would be a class I substance and would be subject to the same production phaseout as the CFCs and halons. This effectively eliminated some potential substitutes, such as FM-100, and mixtures using CFCs. Title VI of the U.S. Clean A i r Act of 1990 enacts the U.S. strategy to comply with the Montreal Protocol for protection of the stratospheric ozone layer (10). Title VI is administered by the Stratospheric Protection Division within the Office of Air and Radiation. Section 612 of that Title directs E P A to set up a program, named ' S N A P ' or the Significant New Alternatives Policy program, to evaluate any halon substitute or alternative technology to ensure that the substitutes reduce the overall risk to human health and the environment and to promote these substitutes to achieve rapid market acceptance. EPA's goal is to ensure that industry and consumers have ample choices for the diversity of applications in which CFCs and halons are currently used. EPA adopted a risk balancing approach on health and safety issues by looking at use of the agent in each sector under likely exposure pathways. "The risk to individuals from exposure to halon substitutes is generally from discharges that occur infrequently. Chronic effects are not the usual concern for halon substitutes because when used, these substances are discharged in high concentrations over short periods of time, and thus, are potentially acutely hazardous. Risk from exposure to halon substitutes is accordingly best assessed by analysis of acute toxic effects associated with exposure to these compounds,



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such as developmental toxicity and cardiotoxicity. In most instances, cardiotoxicity occurs at lower levels than fetotoxicity, and therefore, unless otherwise warranted by the developmental data, E P A will base the estimates for emergency limits during halon use on the no observable adverse effect level (NOAEL) and lowest observable adverse effect level (LOAEL) reported for epinephrine-sensitized cardiotoxicity in dogs (and in a few instances monkeys). Human heart arrhythmias and sudden death resulting from overexposure to CFCs, halons, other halogenated and nonhalogenated hydrocarbons have been documented in work place settings and in volatile substance abuse (e.g., glue sniffing) (77)." To assess the safety of an agent for use in a total flooding system, E P A analysts examine the actual design concentration as N F P A defines it (72) (cup burner plus 20%) or in some cases the actual large scale testing design concentration, and compare this value to the cardiotoxic effect levels. It is a different situation for streaming agents because it is a localized application, and the air exchange further dilutes the concentration of the agent. EPA requires manufacturers to submit data acquired by personal monitoring for the anticipated usage. A device is attached to the breathing zone of a firefighter to collect samples of the actual levels of exposure. The results of these tests show that actual exposure is much lower than what the models predict. Consequently, E P A has listed agents as acceptable, even with L O A E L as low as 1.0 or 2.0 percent (13). In fact, Halon 1211 (CF ClBr) has a L O A E L of 1.0 percent which shows that these agents can be used safely by trained firefighters (although there are known incidents of accidental deaths with Halon 1211). The conditions stipulated under SNAP for use of total flooding agents are patterned after current Occupational Safety and Health Administration (OSHA) requirements for Halon 1301 (CF Br) systems. Because OSHA does not currently specify the acceptable exposure levels to the substitute agents, E P A is laying these values out very specifically, and has initiated efforts to work with OSHA as that agency takes steps to amend their regulation of fixed gaseous extinguishing systems (OSHA Regulation 1910.162). On environmental criteria, E P A first looks at ozone depletion potential. The Clean A i r Act specifies that any substance with an ODP of 0.2 or higher must be listed by EPA as a class I substance in the United States and must be phased out of production within seven years of listing. While the Clean Air Act does not explicitly define a class II substance, by implication it is an agent with an ODP of less than 0.2. The E P A Administrator is to determine if a substance could significantly damage the stratospheric ozone layer. Currently the chemical with the lowest ODP that E P A has listed as a class II substance is HCFC-123 (CF CHC1 ) with an ODP of 0.02. While EPA considers other environmental media besides ozone depletion potential, including aquatic toxicity, air pollution, etc., global warming potential (GWP) and atmospheric lifetime are the key issues in evaluating halon substitutes. Action #40 of President Clinton's Climate Change Action Plan, released November, 1993, directs E P A to minimize unnecessary emissions of greenhouse gases to help meet the national goal of reducing emissions in the year 2000 to 1990 levels. E P A again has adopted a risk balanced approach 2

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between ODP and GWP and the related atmospheric lifetimes of these agents. However, substitute agents with no ODP tend to be moderate to high global warmers, while those with some ODP tend to be low global warmers. The C A A A directs E P A to "reduce overall risks to human health and the environment (14)." E P A has attempted to characterize emission levels and exposure routes in each use sector in order to minimize environmental impacts. Thus, E P A first looks for the outliers, such as an agent with an extremely long atmospheric lifetime. The perfluorinated carbons (PFCs) are outliers, with atmospheric lifetimes in excess of 3,000 years, and which are virtually indestructible (75). However, because of their extremely favorable toxicity profile, E P A recognizes that they have a role to play in fire protection applications where other agents are not suitable for either technical or safety reasons. Thus, E P A has listed PFCs as acceptable under certain contingent restrictions. Although HFC-23 has a 300 year lifetime (76), E P A recognizes that it is a byproduct of the manufacture of HCFC-22 (CF HC1), which will continue to be produced as a feedstock for the manufacture of polymers such as teflon and thus placed no restriction on its use. The acceptance of this agent adds another choice for users in their arsenal of fire protection agents. In response to environmental and efficacy concerns, fire protection manufacturers are also developing several new alternative technologies, including inert gas systems, water mist systems, and powdered aerosol systems. These nonhalocarbon alternative agents require a different means of determining risk during use. Some of the newer nonhalocarbon alternative agents-the inert gas systems-limit but do not entirely remove the oxygen available to the fire. The most important condition of safe use of such agents is the stipulation that the amount of remaining oxygen in the area is sufficient to maintain Central Nervous System function and that the restriction of oxygen does not impair escape from the area. Powdered aerosol systems present still other risk assessment issues. The conditions determining the safe use of these agents must account for the potential deposition of very small inhalable particles in the respiratory tract. These powder particles may range from very small and potentially respirable into the alveoli to large particles capable of irritation of the upper nasal passages. The size of the particles may be the most significant factor determining risk. Water mist systems using pure water pose little risk, although additives must be evaluated on a case-by-case basis to determine potential health risks. A concern for both mist and powdered aerosol systems is the visual obscuration which occurs during discharge and which may potentially inhibit the ability to egress the area. Because the risk analyses of these alternative technologies differs somewhat from the standard E P A risk assessment procedures, E P A has encouraged the formation of ad hoc workshops and medical peer review panels to characterize the risk issues presented by each new technology and to help delineate the appropriate exposure limits for different clinical groups. Workshops and panels have been formed to analyze issues concerning powdered aerosols and water mists. Conditions describing the appropriate use of inert gases with limited oxygen were evaluated by special medical panels. In addition, 2


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EPA solicited guidance from OSHA on these use conditions since OSHA will ultimately determine the proper usage of all fire suppressant systems.


Halon Banking The EPA's SNAP program has been largely successful in identifying several agents and technologies which can be used in most total flooding and streaming fire protection applications. However, there are still some application areas which pose technical challenges, including aviation, military tanks, some military shipboard uses, and explosion inertion applications. The U.S. military has been a leader in research and development efforts, and has selected HFC-125 (CHF CF ) for the design of systems on new military aircraft. For commercial aircraft, the Federal Aviation Administration (FAA) is spearheading an industry wide R & D effort to identify effective substitutes. However, once an agent is identified for complex systems, much work still remains to design, manufacture and certify not only the fire protection system but the entire redesign of, for example, the aircraft itself. To serve existing equipment that cannot be cost-effectively retrofitted, EPA encourages halon banking programs. The Department of Defense maintains such a bank for mission critical systems, managed by the Defense Logistics Agency, which also serves as the buffer needed while new agents are identified and systems developed for new platforms. In the commercial sector, users have undertaken similar actions to redeploy and bank halon. Private-sector business have sprung up to work the halon recycling market, and the non-profit Halon Recycling Corporation plays an important role in aiding buyers and sellers of halon both in the U.S. and abroad. 2

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Conclusion The collaborative efforts of industry, military, end-users, and regulators described in this chapter is a success story. Not only has this community of professionals and citizens contributed significantly to ozone layer protection, but they have gone the extra length to recognize the broader environmental implications of chemical use and fire fighting practices. Environmental protection, in this case, has truly evolved to pollution prevention and stewardship of the earth's ecosystem. Literature Cited 1. J.D. Longstreth et al., "Effects of Increased Solar Ultraviolet Radiation on Human Health" in Environmental Effects of Ozone Depletion: 1994 Assessment, ed. J . C . van der Leun (Nairobi, Kenya: United Nations Environment Programme, Nov. 1994), pp. 23-48.



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2. Solomon, S.,Wuebbles, D . , et al., "Ozone Depletion Potentials, Global Warming Potentials, and Future Chlorine/Bromine Loading" In Scientific Assessment of Ozone Depletion: 1994; Cochairs, Albritton, Daniel L . , Watson, Robert T . , and Aucamp, Piet J.; World Meteorological Organization: Geneva, Switzerland, 1994; pp. 13.9-13.13. 3. U.S. Environmental Protection Agency. Risk Screen on the use of Substitutes for Class I Ozone Depleting Substances: Fire Suppression and Explosion Protection. Washington, D . C . : E P A , March 1994. p. 2-2 to 2-4. 4. U.S. Environmental Protection Agency. Global Change Division. "Integrated Assessment Model" and from "Atmospheric and Health Effects Framework" model run for Regulatory Impact Analysis. Washington, D . C . : U . S E P A , 1987; 1992. 5. Taylor, Gary. "Halon Bank Management - A Rationale to Evaluate Future World Supplies." In Proceedings of the Second International Conference on Halons and the Environment. Geneva, Switzerland: C F P A Europe/NFPA, Sept. 28, 1990. 6. Environment Canada. Halon Bank Management - A Rationale for Canada. March 15, 1990. 7. Halon Fire Extinguishing Agents Technical Options Report to the United Nations Environment Programme Technology Review Panel. Gary Taylor and Major E . Thomas Morehouse Jr., Co-Chairmen. Toronto, Canada: June, 1989), p. 9. 8. Solomon S., Wuebbles D . , et al.; "Ozone Depletion Potentials, Global Warming Potentials, and Future Chlorine/Bromine Loading" in Scientific Assessment of Ozone Depletion: 1994; Cochairs Albritton, Daniel L., Watson, Robert T . , and Aucamp, Piet J.; World Meteorological Organization: Geneva, Switzerland, 1994; p. 13.13. 9. Ozone Secretariat. Handbook for the Montreal Protocol on Substances that Deplete the Ozone Layer. Nairobi, Kenya: United Nations Environment Programme. Third edition, Aug. 1993. p. 27. 10. Clean Air Act. U.S. Code, Title VI, vol. 42, secs. 7450 et seq. (1990). 11. Rubenstein, Reva. "Human health and environmental toxicity issues for evaluation of halon replacements." Toxicology Letters. (1993), 68, pp. 21-24. 12. National Fire Protection Association. NFPA 12A: Halon 1301 Fire Extinguishing Systems. Quincy, Massachusetts: N F P A , 1992. p. 12A-11. 13. U.S. Environmental Protection Agency. Significant New Alternatives Policy Program, rulemakings and notices. 59 FR 13044 (March 18, 1994); 59 FR 44240 (August 26, 1994); 60 FR 3318 (January 13, 1995). 14. Clean Air Act. U.S. Code, vol. 42, secs. 7401 et seq. "Title VI", sec. 612(a), (1990). 15. Ravishankara, A . R . et al. "Atmospheric Lifetimes of Long-Lived Halogenated Species." Science. January 8, 1993, 259, pp. 194-199. 16. Du Pont Fluorochemicals. "EPA SNAP Submission for HFC-23." Jan. 1993. RECEIVED June 12,1995


The History of the Halon Phaseout and Regulation ... - ACS Publications

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