Jump to main content.


Substitutes for Halon 1301 as a Total Flooding Agent

Substitutes are reviewed on the basis of ozone depletion potential, global warming potential, toxicity, flammability, and exposure potential. Lists of acceptable and unacceptable substitutes are updated several times each year. A chronological list of SNAP updates is also available.

Note: SNAP Notices and Final Rules published in the Federal Register take precedence over all information on the web site.

Acceptable Substitutes for Halon 1301 in Total Flooding Systems

Substitute (Trade Name) Comments
Powdered Aerosol C (PyroGen, Soyuz) For use in unoccupied areas only.
Powdered Aerosol A (SFE) For use in unoccupied areas only.
Carbon Dioxide System design must adhere to OSHA 1910.162(b)(5) and NFPA Standard 12
Water None
Water Mist Systems using Potable or Natural Sea Water None
Foam A [formerly Water Mist / Surfactant Blend A] (Phirex+) This agent is not a clean agent, but is a low-density, short duration foam.
HCFC-22 Use of blends containing this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

The NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems gives guidelines for blends that contain HFC-134a or HCFC-22 and other acceptable total flooding agents, rather than referring to HFC-134a or HCFC-22 alone.

See additional comments 1, 2, 3, 4, 5.

HCFC-124 Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

See additional comments 1, 2, 3, 4, 5.

[HCFC Blend] A (NAF S-III) Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

See additional comments 1, 2, 3, 4, 5.

HFC-23 (FE-13) Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

See additional comments 1, 2, 3, 4, 5.

HFC-125 (FE 25) Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

See additional comments 1, 2, 3, 4, 5.

HFC-227ea (FM-200, FE-227) Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

See additional comments 1, 2, 3, 4, 5.

HFC-134a Use of blends containing this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

The NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems gives guidelines for blends that contain HFC-134a or HCFC-22 and other acceptable total flooding agents, rather than referring to HFC-134a or HCFC-22 alone.

See additional comments 1, 2, 3, 4, 5.

IG-100 (NN 100) Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

See additional comments 1, 2, 5.

IG-01 (Argotec; formally Inert Gas Blend C) Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

See additional comments 1, 2, 5.

IG-55 (Argonite; formally Inert Gas Blend B) Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

See additional comments 1, 2, 5.

IG-541 (Inergen) Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

This agent contains CO2, which is intended to increase blood oxygenation and cerebral blood flow in low oxygen atmospheres. The design concentration should result in no more than 5% CO2.

See additional comments 1, 2, 5.

C6-perfluoroketone [1,1,1,2,2,4,5,5,5-nonafluoro-4-(trifluoromethyl)-3-pentanone] (Novec 1230) Use of the agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

For operations that install and maintain total flooding systems using this agent, EPA recommends the following:
- install and use adequate ventilation ;
- clean up all spills immediately in accordance with good industrial hygiene practices; and
- provide training for safe handling procedures to all employees that would be likely to handle containers of the agent or extinguishing units filled with the agent.

See additional comments 1, 2, 3, 4, 5.

Gelled Halocarbon /Dry Chemical Suspension (Envirogel) with ammonium polyphosphate additive Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems, for whichever hydrofluorocarbon gas is employed.

See additional comments 1, 2, 3, 4, 5.

HFC-125 with 0.1% d-limonene (NAF S-125) Use of the agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

Extinguisher bottles should be clearly labeled with the potential hazards associated with the use of HFC-125 and d-limonene, as well as handling procedures to reduce risk resulting from these hazards.

See additional comments 1, 2, 3, 4, 5.

HFC-227ea with 0.1% d-limonene (NAF S 227) Use of the agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

Extinguisher bottles should be clearly labeled with the potential hazards associated with the use of HFC-227ea and d-limonene, as well as handling procedures to reduce risk resulting from these hazards.

See additional comments 1, 2, 3, 4, 5.

Uni-light Advanced Fire Fighting Foam 1% water mist system (Uni-light AFFF 1%) This agent is intended for use onboard ships and in off-shore installations. It may be used both in normally occupied and unoccupied areas.

Appropriate personal protective equipment should be worn during manufacture or in the event of a release. Personal protective equipment should include safety goggles, protective gloves, and a self-contained breathing apparatus.

Supply bottles for the foam should be clearly labeled with the potential hazards associated with the use of the chemicals in the foam, as well as handling procedures to reduce risk resulting from these hazards.

Use should conform with relevant OSHA requirements, including 29 CFR1910, Subpart L, Sections 1910.160

Victaulic Vortex Systems

EPA recommends that users consult Section VIII of the Occupational Safety & Health Administration (OSHA) Technical Manual for information on selecting the appropriate types of Personal Protective Equipment (PPE).

EPA recommends that use of this system should be in accordance with the safe exposure guidelines for inert gas systems in the latest edition of NFPA 2001, specifically the requirements for residual oxygen levels, and should be in accordance with the relevant operational requirements in NFPA 750 Standard on Water Mist Fire Protection Systems.

ATK OS-10

EPA recommends that users consult Section VIII of the Occupational Safety & Health Administration (OSHA) Technical Manual for information on selecting the appropriate types of Personal Protective Equipment (PPE).

EPA recommends that use of this system should be in accordance with the safe exposure guidelines for inert gas systems in the latest edition of NFPA 2001, specifically the requirements for residual oxygen levels, and should be in accordance with the relevant operational requirements in NFPA Standard 2010 for Aerosol Extinguishing Systems.

See additional comments 1 and 5.

Firebane® 1179 Follow the manufacturer’s guidelines in the MSDS.
N2 Towers® System EPA recommends that use of this system should be in accordance with the safe exposure guidelines for inert gas systems in the latest edition of NFPA 2001 Standard on Clean Agent Fire Extinguishing Systems, specifically the requirements for residual oxygen levels, and use should be in accordance with the NFPA Standard 2010 for Aerosol Extinguishing Systems.
Surfactant Blend A (Cold Fire® ) Observe recommendations in the manufacturer’s MSDS and guidance for using this substitute.
Solution of 50% potassium acetate and 50% water (K-Ace) EPA recommends that use of this system should be in accordance with the manufacturer’s MSDS.

EPA recommends that users consult Section VIII of the OSHA Technical Manual for information on selecting the appropriate types of personal protective equipment for all listed fire suppression agents. EPA has no intention of duplicating or displacing OSHA coverage related to the use of personal protective equipment (e.g., respiratory protection), fire protection, hazard communication, worker training or any other occupational safety and health standard with respect to EPA’s regulation of halon substitutes.

Use must conform to relevant OSHA requirements, including 29 CFR Part 1910, subpart L, sections 1910.160 and 1910.162.

Substitutes for Halon 1301 Subject to Use Conditions in Total Flooding Systems

Substitute (Trade Name) Conditions or Restrictions Comments
Inert Gas/Powdered Aerosol Blend (FS 0140) For use in normally unoccupied areas only.

Any employee who could possibly be in the area must be able to escape within 30 seconds.

The employer shall assure that no unprotected employees enter the area during discharge.

The manufacturer's SNAP application requested listing for use in unoccupied areas only.

See additional comment 2.

Powdered Aerosol D (Aero K/Stat X) For use only in normally unoccupied areas. Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2010 standard for Aerosol Extinguishing Systems.

For establishments manufacturing the agent or filling, installing, or servicing containers or systems to be used in total flooding applications, EPA recommends the following:
- adequate ventilation should be in place to reduce airborne exposure to constituents of agent;
- an eye wash fountain and quick drench facility should be close to the production area;
- training for safe handling procedures should be provided to all employees that would be likely to handle containers of the agent or extinguishing units filled with the agent;
- workers responsible for clean up should allow for maximum settling of all particulates before reentering area and wear appropriate protective equipment; and
- all spills should be cleaned up immediately in accordance with good industrial hygiene practices.

See additional comments 1, 2, 3, 4, 5.

Powdered Aerosol E (Fire Pro) For use only in normally unoccupied areas. Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2010 standard for Aerosol Extinguishing Systems.

For establishments manufacturing the agent or filling, installing, or servicing containers or systems to be used in total flooding applications, EPA recommends the following:
- adequate ventilation should be in place to reduce airborne exposure to constituents of agent;
- an eye wash fountain and quick drench facility should be close to the production area;
- training for safe handling procedures should be provided to all employees that would be likely to handle containers of the agent or extinguishing units filled with the agent;
- workers responsible for clean up should allow for maximum settling of all particulates before reentering area and wear appropriate protective equipment; and
- all spills should be cleaned up immediately in accordance with good industrial hygiene practices.

See additional comments 1, 2, 3, 4, 5.

Gelled Halocarbon /Dry Chemical Suspension with sodium bicarbonate (Envirogel B25 + 36) Use of whichever hydrofluorocarbon gas (HFC-125, HFC-227ea, or HFC-236fa) is employed in the formulation must be in accordance with all requirements for acceptability (i.e., narrowed use limits) of that HFC under EPA’s SNAP program. Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems, for whichever hydrofluorocarbon gas is employed, and the latest edition of the NFPA 2010 standard for Aerosol Extinguishing Systems.

Sodium bicarbonate release in all settings should be targeted so that increased blood pH level would not adversely affect exposed individuals.

Users should provide special training, including the potential hazards associated with the use of the HFC agent and sodium bicarbonate, to individuals required to be in environments protected by Envirogel with sodium bicarbonate additive extinguishing systems.

Each extinguisher should be clearly labeled with the potential hazards from use and safe handling procedures.

See additional comments 1, 2, 3, 4, 5.

Phosphorous tribromide (PhostrEx) For use only in aircraft engine nacelles. For establishments manufacturing the agent or filling, installing, or servicing containers or systems, EPA recommends the following:
- adequate ventilation should be in place and/or positive pressure, self-contained breathing apparatus (SCBA) should be worn;
- training for safe handling procedures should be provided to all employees that would be likely to handle containers of the agent or extinguishing units filled with the agent; and
- all spills should be cleaned up immediately in accordance with good industrial hygiene practices.

See additional comments 1, 2, 3, 4, 5.

Powdered Aerosol F (KSA®) For use only in normally unoccupied areas. Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2010 standard for Aerosol Extinguishing Systems.  

For establishments filling, installing,  servicing, using, or disposing of containers or systems to be used in total flooding applications, EPA recommends the following:
-  appropriate protective clothing (e.g., goggles, particulate removing respirators, and gloves) should be worn during the  installation and maintenance of the extinguishing units filled with the agent or during clean up and disposal of this agent;
- training should be provided to all employees that would be likely to handle containers of the agent or extinguishing units filled with the agent, required to clean up after discharge or required to work near spaces protected by Powdered Aerosol F.  

Releases in all settings should be limited to an appropriate design concentration for the protected space so that increased blood pH level would not adversely affect exposed individuals.  

Exposed individuals should be given an electrolyte solution to drink afterwards to restore the pH within the appropriate range.

Each extinguisher should be clearly labeled with the potential hazards from use and safe handling procedures.  

In the case of an accidental spill, the area should be well-ventilated, and workers should wear protective equipment while following good industrial hygiene practices for clean-up and disposal.  

See additional comments 1, 2, 4, 5.

Powdered Aerosol G (Dry Sprinkler Powdered Aerosol (DSPA) Fixed Generators) For use only in normally unoccupied areas. Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2010 standard for Aerosol Extinguishing Systems.  

DSPA generators produce combustion byproducts (micron-sized dry particles and a gaseous mixture), that mix together into a uniform fire-extinguishing aerosol before being released into the protected area.  The propellant components of the system generates inert gases, which function to physically extinguish the fire by the combined effects of straining the burning flame front and reducing the heat of the combustion sources.  The small aerosol particles have a high surface area­to-volume ratio, which increases their ability to rapidly distribute throughout enclosed areas and to act as heat sinks.   

For establishments filling, installing,  servicing, using or disposing of generator units or systems  in total flooding applications, EPA recommends the appropriate protective clothing (e.g., goggles, particulate removing respirators, and gloves) should be worn during the installation and maintenance of the extinguishing units filled with the agent or during clean up and disposal of this agent.  

Powdered Aerosol G should be collected by hand (e.g., with a dustpan and duster or a vacuum cleaner); waste should be collected in suitable drums for disposal and the area should be washed clean with sufficient quantities of water; and training should be provided to all employees that would be likely to handle the agent or generator units filled containing the agent, required to clean up after discharge or required to work near spaces protected by Powdered Aerosol G fixed generator total flooding systems.  

In accordance with Department of Health and Human Services regulations (42 CFR Part 84), safety glasses and a NIOSH/CDC-approved N99 respirator are required for individuals installing Powdered Aerosol G fixed systems.  

Each generator unit should be clearly labeled with the potential hazards from use and safe handling procedures.  

In the case of an accidental discharge, the area should be well-ventilated, and workers should wear protective equipment while following good industrial hygiene practices for clean-up and disposal.  

See additional comments 1, 2, 4, 5, 6.

Substitutes for Halon 1301 Subject to Narrowed Use Limits in Total Flooding Systems

Substitute (Trade Name) Conditions or Restrictions Comments
HFC-236fa (FE-36) Acceptable when manufactured using any process that does not convert perfluoroisobutylene (PFIB) directly to HFC-236fa in a single step:
  • for use in explosion suppression and explosion inertion applications, and
  • for use in fire suppression applications where other non-PFC agents or alternatives are not technically feasible due to performance or safety requirements;
  1. because of their physical or chemical properties, or
  2. where human exposure to the extinguishing agents may result in failure to meet safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Extinguishing Systems.
Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

The comparative design concentration based on cup burner values is approximately 6.4%.

Users should observe the limitations on HFC-236fa acceptability by taking the following measures:

  1. conduct an evaluation of foreseeable conditions of end use;
  2. determine that the physical or chemical properties or other technical constraints of the other available agents preclude their use;
  3. determine that human exposure to the other alternative extinguishing agents may result in failure to meet applicable use conditions;

Documentation of such measures should be available for review upon request.

Feasible for use in a normally occupied area.

The principal environmental characteristic of concern for HFC-236fa is its high GWP of 9400 and long atmospheric lifetime of 226 years. Actual contributions to global warming depend upon the quantities emitted.

See additional comments 1, 2, 3, 4, 5.

C3F8 (PFC-218, CEA-308) Acceptable for nonresidential uses where other alternatives are not technically feasible due to performance or safety requirements;
  1. because of their physical or chemical properties; or
  2. where human exposure to the extinguishing agents may result in failure to meet safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Extinguishing Systems.
Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

The comparative design concentration based on cup burner values is approximately 8.8%.

Users should observe the limitations on PFC acceptability by taking the following measures:

  1. conduct an evaluation of foreseeable conditions of end use;
  2. determine that the physical or chemical properties or other technical constraints of the other available agents preclude their use;
  3. determine that human exposure to the other alternative extinguishing agents may result in failure to meet applicable use conditions;
Documentation of such measures should be available for review upon request.

The principal environmental characteristic of concern for PFCs is that they have high GWPs and long atmospheric lifetimes. Actual contributions to global warming depend upon the quantities of PFCs emitted.

For additional guidance regarding applications in which PFCs may be appropriate, users should consult the description of potential uses which is included in the March 18, 1994, final rule (59 FR 13044).

See additional comments 1, 2, 3, 4, 5.
C4F10 (PFC-410, CEA-410) Acceptable for nonresidential uses where other alternatives are not technically feasible due to performance or safety requirements;
  1. because of their physical or chemical properties; or
  2. where human exposure to the extinguishing agents may result in failure to meet safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Extinguishing Systems.
Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

The comparative design concentration based on cup burner values is approximately 6.6%.

Users should observe the limitations on PFC acceptability by taking the following measures:

  1. conduct an evaluation of foreseeable conditions of end use;
  2. determine that the physical or chemical properties or other technical constraints of the other available agents preclude their use;
  3. determine that human exposure to the other alternative extinguishing agents may result in failure to meet applicable use conditions;
Documentation of such measures should be available for review upon request.

The principal environmental characteristic of concern for PFCs is that they have high GWPs and long atmospheric lifetimes. Actual contributions to global warming depend upon the quantities of PFCs emitted.

For additional guidance regarding applications in which PFCs may be appropriate, users should consult the description of potential uses which is included in the March 18, 1994, final rule (59 FR 13044).

See additional comments 1, 2, 3, 4, 5.
SF6 Only for use as a discharge agent in military applications and in civilian aircraft. Users should limit testing only to that which is essential to meet safety or performance requirements.

This agent is used only to test new Halon 1301 systems.

CF3I Use only in normally unoccupied areas. Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

See additional comments 1, 2, 3, 4, 5.

Haltron II Acceptable in areas that are not normally unoccupied only. See additional comments 1, 2, 3, 4, 5.
Gelled Halocarbon /Dry Chemical Suspension (Envirogel) with any additive other than ammonium polyphosphate or sodium bicarbonate Use only in normally unoccupied areas. Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems, for whichever hydrofluorocarbon gas is employed.

See additional comments 1, 2, 3, 4, 5.

HFC227-BC Sodium bicarbonate release in all settings should be targeted so that increased pH level would not adversely affect exposed individuals. Users should provide special training to individuals required to be in environments protected by HFC227–BC extinguishing systems.

Each HFC227–BC extinguisher should be clearly labeled with the potential hazards from use and safe handling procedures.

Use of this agent should be in accordance with the safety guidelines in the latest edition of the NFPA 2001 Standard for Clean Agent Fire Extinguishing Systems.

See additional comments 1, 2, 3, 4, 5.


Unacceptable Substitutes for Halon 1301 in Total Flooding Systems

Substitute (Trade Name) Comments
HFC-32 This agent is flammable.
Chlorobromomethane Other alternatives exist with zero or lower ODP; OSHA regulations prohibit its use as extinguishing agent in fixed extinguishing systems where employees may be exposed. See 29 CFR 1910.160(b)(11).
HBFC-22B1 (FM-100) HBFC-22B1 is a Class I ozone-depleting substance with an ozone depletion potential of 0.74. The manufacturer of this agent terminated production of this agent January 1, 1996, except for critical uses, and removed it from the market because it is a fetal toxin.
Additional Comments
  1. Must conform with OSHA 29 CFR 1910 Subpart L Sections 1910.160 and 1910.162.
  2. Per OSHA requirements, protective gear (SCBA) must be available in the event personnel must reenter the area.
  3. Discharge testing should be strictly limited only to that which is essential to meet safety or performance requirements.
  4. The agent should be recovered from the fire protection system in conjunction with testing or servicing, and recycled for later use or destroyed.
  5. EPA has no intention of duplicating OSHA coverage related to the use of personal protective equipment (e.g., respiratory protection), fire protection, hazard communication, worker training or any other occupational safety and health standard with respect to regulation of halon substitutes.
  6. DSPA generators produce combustion byproducts (micron-sized dry particles and a gaseous mixture), that mix together into a uniform fire-extinguishing aerosol before being released into the protected area.  The propellant components of the system generates inert gases, which function to physically extinguish the fire by the combined effects of straining the burning flame front and reducing the heat of the combustion sources.  The small aerosol particles have a high surface area­to-volume ratio, which increases their ability to rapidly distribute throughout enclosed areas and to act as heat sinks, while not displacing oxygen. 

Local Navigation



Jump to main content.