The U.S. Environmental Protection Agency (EPA) has approved new climate-friendly refrigerants, increasing the options for chemicals used in refrigeration and air conditioning equipment in the United States.

The final rule, announced on Monday, was developed as part of the Significant New Alternatives Policy (SNAP) Program, which evaluates substitutes for ozone-depleting chemicals that are being phased out under the stratospheric ozone protection provisions of the Clean Air Act.

It includes:

  • Ethane in very low temperature refrigeration and in non-mechanical heat transfer;
  • Isobutane in retail food refrigeration (stand-alone commercial refrigerators and freezers) and in vending machines;
  • Propane in household refrigerators, freezers, or combination refrigerators and freezers, in vending machines and in room air conditioning units;
  • The hydrocarbon blend R-441A in retail food refrigeration, in vending machines and in room air conditioning units; and
  • HFC-32 (difluoromethane) in room air conditioning units. According to the EPA, HFC-32 has one-third the global warming potential (GWP) of conventional refrigerants currently used in room air conditioning units.

This expands the list of SNAP-approved substitutes to include more low-GWP alternatives that can replace both the ozone-depleting substances and high-GWP hydrofluorocarbons (HFCs), the agency explained. The approved substitutes have GWP values ranging from 3 to 675 and can replace older compounds with GWPs of between 1400 to 4000.

These refrigerants are already in use in many of these applications in Europe and Asia, the EPA pointed out.

The agency is also exempting all of these substances, except HFC-32, from the Clean Air Act refrigerant venting prohibition. This is because current evidence suggests that their venting, release or disposal does not pose a threat to the environment.