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Questions and Answers on Halons and Their Substitutes

This page provides a series of questions and answers on the regulations governing the production and use of halons and the development of substitute agents for fire suppression and explosion protection.

If you have questions beyond those in this fact sheet, or would like paper copies of the lists, please call the Stratospheric Ozone Protection Hotline toll-free at 1 (800) 296-1996 or direct dial (202) 343-9210 to leave inquiries.

You can also read more about EPA's Significant New Alternatives Policy (SNAP) Program, which evaluates alternatives for ozone-depleting substances.

General Questions

A. The Phaseout of Halons

  1. When was the production of halons banned?
  2. Must I now dismantle my halon fire protection system?
  3. Are there any federal laws on emissions of halons?

B. Halon Recycling and Banking

  1. Where can I purchase recycled halon?
  2. What is the HRC?
  3. Who set up the HRC?
  4. What do you mean by the term "critical use"?
  5. How is a use designated as critical?
  6. Why do these distinctions matter?
  7. What are the terms of the contract if I want to buy or sell halons through the HRC?
  8. How can I contact the HRC?
  9. Are there standards for recycled halon?
  10. Is recycling equipment available?
  11. Can I import halon?

C. Halon Disposal

  1. I am removing halon from my systems. I don't want to use it again. What can I do with it?
  2. Will the HRC come to take my halon?
  3. What if I can't find anyone to buy my halon because I have too little for it to be of interest or because I have Halon 1211 or Halon 2402?
  4. Tell me more about the DoD bank.
  5. How can I contact the DoD Bank?
  6. Are there any federal laws on the disposal of halons and halon-containing equipment?

D. SNAP Status and Review Process

  1. What does SNAP stand for?
  2. What is EPA doing under the SNAP program?
  3. When were the SNAP lists published in the Federal Register?
  4. What is the difference between a 'Notice,' a 'Proposed Rule' (Proposal), and a 'Final Rule' (Rule)?
  5. Will there be other agents available in the future?
  6. How does EPA decide whether a substitute is acceptable or unacceptable?
  7. What are the most significant criteria for evaluating a halocarbon halon substitute?
  8. Are there any restrictions on the use of these agents?
  9. I heard that HCFCs are not acceptable halon substitutes.
  10. What are the SNAP limitations on using a PFC (either C4F10, C6F14 or C3F8) in the U.S.?
  11. Do I have to obtain EPA approval to use a PFC?
  12. What is the SNAP status of alternative technologies such as inert gases, water mist, and powdered aerosols?
  13. What are the SNAP conditions on the use of inert gases, which work by lowering the oxygen level?
  14. Are there conditions on using water mist or water fog systems?
  15. Can I use a powdered aerosol in a total flooding system in an occupied area?
  16. What alternatives are suitable for my particular end use?
  17. How can I contact the vendors of these substitutes?
  18. How can I obtain copies of the SNAP rules and notices?
  19. Are the rules and notices available electronically?
  20. What other government regulations or industry standards concerning halons should I be aware of?
  21. Where can I obtain additional information about the SNAP program and likely alternatives for halon?

A. The Phaseout of Halons

  1. When was the production of halons banned?
    Under the Clean Air Act (CAA), the U.S. banned the production and import of virgin halons 1211, 1301, and 2402 beginning January 1, 1994 in compliance with the Montreal Protocol On Substances That Deplete The Ozone Layer. Recycled halon and inventories produced before January 1, 1994, are now the only sources of supply.

    EPA's final rule published March 5, 1998 (63 FR 11084) (14 pp, 222KB), bans the formulation of any blend of two or more of these halons with one exception. An exemption is provided for halon blends formulated using recycled halon solely for the purpose of aviation fire protection, provided that blends produced under this exemption are recycled to meet the relevant purity standards for each individual halon. A fact sheet summarizing this rule is also available.

  2. Must I now dismantle my halon fire protection system?
    No. It is legal to continue to use your existing halon system. It is even legal to purchase recycled halon and halon produced before the phaseout to recharge your system.

    However, due to the fact that halons deplete the ozone layer, users are encouraged to consider replacing their system and making their halon stock available for users with more critical needs.

  3. Are there any federal laws on emissions of halons?
    EPA's final rule published March 5, 1998 (63 FR 11084) prohibits the intentional release of Halon 1211, Halon 1301, and Halon 2402 during the testing, repairing, maintaining, servicing or disposal of halon-containing equipment or during the use of such equipment for technician training. The rule also requires appropriate training of technicians regarding emissions reduction and proper disposal of halon and halon-containing equipment. See the guidance document for more information (20 pp, 1.78 MB). The rule became effective April 6, 1998.
    Return to list of questions

B. Halon Recycling and Banking

  1. Where can I purchase recycled halon?
    Recycled halon can be purchased from many halon and fire protection equipment distributors or directly from owners who are decommissioning their halon systems. In addition, the Halon Recycling Corporation (HRC) may be able to provide information on such sellers.

  2. What is the HRC?
    The HRC is a non-profit information clearinghouse established to assist sellers wishing to dispose of halon in a responsible manner, and to help buyers with "critical uses" locate supplies of Halon 1301 and Halon 1211 for recharging their existing systems. 

  3. Who set up the HRC?
    The HRC was established by members of the fire protection community and by the Halon Alternatives Research Corporation (HARC), an industry consortium that promotes the research, development, and use of alternatives to halons for fire protection. 

  4. What do you mean by the term "critical use"?
    The term "critical use" is used by HRC to identify priority uses of recycled halon. A use is considered "critical" when a need exists "to minimize damage due to fires, explosions, or other extinguishing agents, which would otherwise result in serious impairment of an essential service to society or pose an unacceptable threat to life, the environment, or national security even though all other appropriate fire protection measures have been taken." 

  5. How is a use designated as critical?
    The HRC has established two ways to make this determination. To be "registered," a buyer must sign a self-evaluation form. To be "certified," a buyer must submit an application that will be reviewed by an independent review committee. The committee certifies that the user has a legitimate need to continue using halon, taking into account technological, economic, and legal considerations. 

  6. Why do these distinctions matter?
    The HRC facilitates the trade of recycled halon. However, some sellers may want to ensure that their halon is sold only to users with the most critical value to society. The "certified" rating, which is granted by HRC's independent review committee, will provide this assurance. 

  7. What are the terms of the contract if I want to buy or sell halons through the HRC?
    The terms of all transactions are completely between the buyer and the seller. HRC merely acts as a clearinghouse by putting buyers and sellers together. However, HRC will not facilitate transfers of recycled halon from (1) halon-producing countries (developing countries) or from (2) countries that import halon from halon-producing countries. HRC has stated its belief that exporting recycled ozone-depleting substances (ODSs) to developed countries by countries that still produce these ODSs goes against the spirit of the Montreal Protocol.

  8. How can I contact the HRC?
    You can phone the HRC at (800) 258-1283, at (703) 524-6636, or fax (703) 243-2874. You can E-mail the HRC at hrc97@aol.com.

  9. Are there standards for recycled halon?
    The military specification for Halon 1211 has been revised to allow the use of recycled halon. ASTM has developed D5632-95 (Standard Specification for Halon 1301) and D5631-94 (Standard Practice for Handling Transportation and Storage of Halon 1301). ISO 7201 contains standards for halon 1211 and halon 1301.

  10. Is recycling equipment available?
    Yes. Several manufacturers have developed recycling equipment for both Halon 1301 and Halon 1211 that recovers 98-99% of the halon and some units can reclaim it to meet certain specifications. Contact HRC for the list of vendors of recycling equipment. 

  11. Can I import halon?
    It is legal under the Montreal Protocol and the US CAA to import recycled halon, that is, halon that has been recovered from a fire suppression system. Each individual shipment of recycled halon requires prior EPA approval. Approved imports that enter the U.S. must be reported to EPA on a quarterly basis. Newly produced halon or halon never installed in a fire suppression system may not be imported into the U.S. Further information about importing recycled halon may be obtained by calling the Stratospheric Ozone Protection Hotline. The Internal Revenue Service imposes a tax on certain ozone-depleting chemicals. Contact the IRS at (202) 622-3130 to determine whether there is a tax on imported recycled halon.
    Return to list of questions

C. Halon Disposal

  1. I am removing halon from my systems. I don't want to use it again. What can I do with it?
    You can: (1) make it available to critical users through the HRC; (2) donate it to the Department of Defense Ozone Depleting Substances Reserve (DoD bank); (3) return it to your distributor for resale; or (4) send it to a halon recycler. The federal law on the disposal of halons or halon-containing equipment is discussed in question C.6 below.

  2. Will the HRC come to take my halon?
    No. The HRC is not a physical "bank," but is an information clearinghouse that will help you locate a user with a critical need for your halon. The HRC is discussed in Part B above.

  3. What if I can't find anyone to buy my halon because I have too little for it to be of interest or because I have Halon 1211 or Halon 2402?
    HRC and Friends of the Earth (FOE) can help you locate a regional organization that will take your halon as a service. FOE's Healing the Atmosphere Campaign has a grassroots initiative working in communities throughout the U.S. Middle Atlantic and New England states to promote the recovery of halons. Contact Jessica Vallette of FOE at (202) 783-7400 (ext. 227) or e-Mail jvallette@foe.org.

  4. Tell me more about the DoD bank.
    The Defense Logistics Agency (DLA) manages the DoD bank for the U.S. military in order to maintain a reserve of halons 1202, 1211, and 1301 to support "mission critical" requirements when commercial sources are not available. DLA has a policy to rely primarily on DoD turn-ins of recovered halons for future use.

  5. How can I contact the DoD Bank?
    Phone DLA at (804) 279-5203 or (804) 279-4525.

  6. Are there any federal laws on the disposal of halons and halon-containing equipment?
    EPA's rule published March 5, 1998 (63 FR 11084) establishes that halon-containing equipment must be properly disposed of at the end of its useful life. That is, such equipment must be sent for halon recovery to a facility operating in accordance with National Fire Protection Association standards (NFPA 10 and NFPA 12A). The halon itself must be sent for halon recycling to a facility operating in accordance with NFPA 10 and NFPA 12A, or for destruction using one of several controlled processes identified in the regulation. More details can be found on EPA's halons page.
    Return to list of questions

D. SNAP Status and Review Process

  1. What does SNAP stand for?
    SNAP stands for Significant New Alternatives Policy program. EPA set up the SNAP program under Section 612 of Title VI of the CAA, as amended in 1990. 

  2. What is EPA doing under the SNAP program?
    Under SNAP, EPA is evaluating substitute chemicals and alternative technologies that companies want to use in place of the ozone-depleting substances, to ensure that they won't cause greater damage to human health and the environment than the ozone depleters that are being replaced or other alternatives that are available. Based on this evaluation, EPA maintains a list of acceptable substitutes and a list of unacceptable substitutes. 

  3. When were the SNAP lists published in the Federal Register?
    The SNAP Chronology includes links to all SNAP rulemakings. A complete list of Fire Suppression and Explosion Protection Substitutes is found here.

  4. What is the difference between a 'Notice,' a 'Proposed Rule' (Proposal), and a 'Final Rule' (Rule)?
    A 'Notice' contains no regulatory controls and thus does not need to go through the notice-and-comment rulemaking process. It may contain technical corrections to earlier rules as well as listings of new agents which are 'Acceptable' without restrictions. It enters into force upon publication in the Federal Register.

    A 'Proposed Rule' (Proposal) contains proposed lists of agents deemed 'Acceptable' (but subject to use restrictions or conditions) or 'Unacceptable'. There is usually a 60-day public comment period beginning with the date of publication in the Federal Register.

    After the public has an opportunity to comment on EPA's proposed rules, EPA considers the comments, prepares a final rule, and a 'Final Rule' (Rule) is published enacting the provisions into law.

  5. Will there be other agents available in the future?
    Yes. Manufacturers are continuing to develop new agents and technologies which EPA will review and which will be included on future SNAP lists. These updated lists will be published periodically in the Federal Register.

  6. How does EPA decide whether a substitute is acceptable or unacceptable?
    EPA's decision on the acceptability of new substitutes proposed by manufacturers is based primarily on the potential human health and environmental risks posed by the substitutes as compared to (in the case of halons) the halon being replaced, as well as to other substitute fire-control agents. The screening of new substitutes is done separately for each specific application, such as for a total flooding agent or for use as a streaming agent. A listing of 'acceptable' does not imply that the agent is necessarily effective for a particular fire hazard or site, and users are advised to consult with a fire protection professional for selection of appropriate agents.

  7. What are the most significant criteria for evaluating a halocarbon halon substitute?
    The key factor in assessing the safety of a halocarbon flooding agent is cardiac sensitization. The amount of flooding agent to extinguish a fire is compared to results of a standard protocol to determine an agent's cardiosensitization levels. This is known as comparing the design concentration to the No Observed Adverse Effect Level (NOAEL) and the Lowest Observed Adverse Effect Level (LOAEL).

  8. Are there any restrictions on the use of these agents?
    These halocarbon substitutes are generally subject to use restrictions under the SNAP program. Please see the SNAP rules for complete details of the use restrictions for each agent.

    When using halocarbon substitutes as total flooding agents the following conditions, which were adopted from an OSHA safety and health standard (29 CFR 1910 Subpart L), generally apply:

    • Where egress from a normally occupied area cannot be accomplished within one minute, the employer shall not use the agent in concentrations exceeding its "No Observed Adverse Effect Level" (NOAEL).
    • Where egress from a normally occupied area takes longer than 30 seconds but less than one minute, the employer shall not use the agent in a concentration greater than its cardiotoxic "Lowest Observable Adverse Effect Level" (LOAEL).
    • Agent concentrations greater than the LOAEL are only permitted in areas not normally occupied by employees provided that any employee in the area can escape within 30 seconds. The employer shall assure that no unprotected employees enter the area during agent discharge.

    Halocarbon substitutes being used as streaming agents are restricted to non-residential uses.

  9. I heard that HCFCs are not acceptable halon substitutes.
    Under section 610(d) of the CAA, Congress requires EPA to ban the use of a class of substances including HCFCs in all `pressurized dispensers,' but allows EPA to grant exceptions from this ban in certain circumstances. Portable fire extinguishers fall under the definition of pressurized dispensers. In a final rule published by EPA on December 4, 1996 (61 FR 64424) EPA provided an exemption to the ban at CAA 610(d) for portable non-residential fire extinguishers; thus, EPA allows the sale and distribution of HCFCs for this use.

    In addition, HCFCs in total flooding systems and fixed streaming systems are not subject to the ban at CAA 610(d) because these systems don't fall under the definition of pressurized dispensers.

    For more specific guidance, contact the Stratospheric Ozone Protection Hotline or the Nonessential Products Ban Program Coordinator at (202) 564-9729.

  10. What are the SNAP limitations on using a PFC (either C4F10, C6F14 or C3F8) in the U.S.?
    PFCs may only be used where no other agent is technically feasible due to performance or safety requirements. The user must conduct an evaluation of the other alternatives and must determine that they either will not perform properly or that they will pose a risk to human health. In addition, PFC use must meet the conditions discussed in question D.8 above.

  11. Do I have to obtain EPA approval to use a PFC?
    No approval is required from EPA. However, the user must maintain documentation of the evaluation.

  12. What is the SNAP status of alternative technologies such as inert gases, water mist, and powdered aerosols?
    Non-halocarbon systems are considered "alternative technologies" and are subject to EPA SNAP review on the basis of ozone depletion potential, global warming potential, toxicity, flammability, and exposure potential. Several alternative technologies have been listed acceptable, and some are subject to use conditions or restrictions.

  13. What are the SNAP conditions on the use of inert gases, which work by lowering the oxygen level?
    Inert gas systems work by lowering the oxygen in a room to a level that will not sustain combustion, while remaining high enough to sustain human life.

    SNAP requires that the oxygen level must not fall below 10% if employees can egress the area within one minute; the oxygen level must be designed to the 12% level if it takes longer than one minute to egress the area. The CO2 level must not exceed 5%.

    Three inert gases are listed acceptable by SNAP: IG-01, IG-55, and IG-541. A fourth inert gas, IG-100, was proposed as an acceptable halon substitute (with use restrictions) on Feb. 18, 1999; final action on this agent is pending.

  14. Are there conditions on using water mist or water fog systems?
    EPA has listed water mist systems using potable water or natural sea water as acceptable without use restrictions or conditions. However, any system with an additive must be reviewed by EPA on a case-by-case basis.

  15. Can I use a powdered aerosol in a total flooding system in an occupied area?
    Powdered aerosol in total flooding systems have not undergone a medical panel peer review for physiological effects, and thus they have only been listed as acceptable in normally unoccupied areas.

  16. What alternatives are suitable for my particular end use?
    EPA maintains a list of acceptable substitutes, but it is up to manufacturers and users to assess their suitability for particular uses.

  17. How can I contact the vendors of these substitutes?
    A list of representatives of makers of halon substitutes who submitted notices to SNAP is available. HARC maintains a list of equipment manufacturers.Exit EPA disclaimer

  18. How can I obtain copies of the SNAP rules and notices?
    The SNAP rules and notices can be ordered from the Stratospheric Ozone Protection Hotline at (800) 296-1996 or 202-564-1613. They can also be ordered for a nominal fee from the Government Printing Office, (202) 512-1800 or fax (202) 512-2250. You must provide them with the date of publication of the rule or notice you want.

  19. Are the rules and notices available electronically?
    All SNAP rulemakings, notices, fact sheets and other publications are available electronically.

  20. What other government regulations or industry standards concerning halons should I be aware of?
    The National Fire Protection Association (NFPA) has published a standards document for halon alternative agents used in total flooding systems. "NFPA 2001 - Standard on Clean Agent Extinguishing Systems" contains design, installation, inspection, test, and use information on halocarbon and inert gas alternatives. The NFPA has also published a standard on water mist systems: "NFPA 750 - Standard for the Installation of Water Mist Fire Protecting System." In addition, manufacturers of systems containing the new alternative agents often obtain Underwriters Laboratories (UL) or Factory Mutual (FM) certification, which means certain standards may apply to the products.

  21. Where can I obtain additional information about the SNAP program and likely alternatives for halon?
    Interested parties may contact the Stratospheric Ozone Protection Hotline toll-free at 1 (800) 296-1996 or direct dial (202) 343-9210 to leave inquiries.

    or

    SNAP Coordinator
    Stratospheric Protection Division
    U.S. EPA 6205J
    Washington, DC 20460
    (202) 564-9163
    FAX (202) 565-2155

    Return to complete list of questions

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