Halon has one of the higher ozone depletion potentials of any compound, and thus its production and use are being curtailed and eventually eliminated. The Montreal Protocol (1987 and subsequent) and the Clean Air Act Amendments (1990) identify Halon 1211 as a Class I ODS and established a ban on its domestic production effective 31 Dec 1993. Currently, halon use is restricted to recycled halon. It is estimated that recycled halon will be available until the end of Fiscal Year 2003.

In order for a substitute to be approved, it must pass certain requirements. These requirements are specific for each branch of the service. The requirements for the Army are: 1) U.S. Environmental Protection Agency (EPA)'s Significant New Alternatives Policy (SNAP) approval and 2) Toxicology clearance from the Army Surgeon General. Both of these requirements must be approved for both the specific application as well as the specific alternative agent.

For the Air Force, the specific application and alternative agent must comply with AFI-32-7086 “Hazardous Materials Management”, and must not impose a greater environmental or safety risk than Halon 1211. If the application is questionable, it must undergo an environmental safety and occupational health evaluation.

The Navy’s requirements are: 1) SNAP approval and 2) An ozone depleting potential (ODP) for the alternative of 0.05 or less (OPNAVINST 5090.1B, Environmental and Natural Resources Program Manual” 1 Nov 94).

In addition to these requirements, the applicable program office (for a weapon system) or fire chief (for an installation) will have regulations and directives that must be satisfied before substitutions are made. Ultimately, it is up to the program office or fire chief to make the substitution, not the user.

Several Halon 1211 substitutes have been approved by the EPA’s SNAP program. Although these substitutes are not ideal replacements for Halon 1211, they may be considered candidates for substitution, subject to specific use conditions as cited in 40 CFR 82 Appendix A to Subpart G, "Substitutes Subject to Use Restrictions and Unacceptable Substitutes." The following substitutes are listed:

• HCFC-123, (banned in residential applications),
• HCFC-124 (FE-241), (banned in residential applications),
• HCFC Blend B (Halotron 1), (banned in residential applications),
• HCFC Blend C (NAF P-III), (banned in residential applications) ,
• HCFC Blend D (Blitz III), (for use in large outdoor application, banned in residential applications),
• Gelled Halocarbon/Dry Chemical Suspension (formerly Powdered Aerosol B),
• Surfactant Blend A,
• Water Mist using potable water or natural sea water,
• Carbon Dioxide,
• Dry Chemical,
• Water, and
• Foam.

The following are acceptable subject to Narrowed Use Limits

• CF₃I (banned in residential applications),
• HBFC-22B1 (due to high ozone-depletion potential this substitute has already been phased out of production),
• C₆F₁₄ (PFC-614 or CEA-614), (acceptable for nonresidential uses when other alternatives are not technically feasible), and
• HFC-227ea (proposed acceptable in nonresidential uses only).

In addition, HFC-236fa (FE-36), HFC-227ea and water mist with additives are pending a decision from EPA.

The majority of Halon 1211 portable fire extinguishers found inside buildings can be replaced with dry chemical extinguishers and/or carbon dioxide extinguishers. However, research and implementation is still ongoing to identify replacements for Halon 1211 extinguishers used in weapon system/specialty applications [fire and rescue vehicles on flight-lines and carrier decks, portable (wheeled) flight-line fire extinguishers, etc.]

A substitute compound may not be as effective in extinguishing a fire, and so a higher concentration or greater quantity of the extinguishing may be required. The alternative for any application should be carefully reviewed for applicability to the use conditions.

Several steps must be taken in order to provide a suitable substitute for Halon 1211:

1. The first step is to identify a need for fire suppression. Since the ban, many 5 lb. Halon 1211 fire extinguishers were pulled without replacements because of a lack of need.

2. The next step is to identify fire suppression requirements. The first requirement is to determine what types of fires are most prominent in the area (A, B, and/or C). The second is to identify where and how often these fires occur. The third requirement is to determine what kind of response is needed (manual or automatic). Once these requirements have been met, then a suitable substitute may be identified.

3. The third step is to find the cheapest and easiest solution. Most of these agents are already stock-listed. There are also commercial products which are acceptable, as long as they are a SNAP-approved agent and a FM/UL delivery system