United States. As part of President Obama's Climate Action Plan, the U.S. Environmental Protection Agency (EPA) is increasing the options for refrigerants used in various types of refrigeration and air conditioning equipment in the United States that offer better climate protection without damaging the ozone layer.
Under the authority of the Clean Air Act, EPA's SNAP Program evaluates chemical substitutes and technologies that are safe for the ozone layer. This final rule expands the list of SNAP-approved substitutes to include alternatives to the lower global global warming potential (GWP) that can replace both ozone-depleting substances and high-global warming potential hydrofluorocarbons (HFCs). Approved substitutes have global warming potential ranging from 3 to 675 and can replace older compounds with PCAs between 1400 and 4000.
After receiving input from industry, environmental groups, and others, EPA is approving low-GWP refrigerants in addition to hydrocarbons, subject to conditions of use, in the following refrigeration and air conditioning applications:
• Ethane in very low temperature refrigeration and in non-mechanical heat transfer;
• Isobutane in retail food refrigeration (stand-alone refrigerators and commercial freezers) and in vending machines;
• Propane in household refrigerators, freezers, refrigerators or combined refrigerators and freezers, in vending machines, and in the air conditioning units of the rooms;
• The mixture of R-441A hydrocarbons in the refrigeration of retail food (stand-alone refrigerators and commercial freezers), in vending machines and air conditioning units in the rooms;
• HFC-32 (difluormethane) in room air conditioning units. HFC-32 has one-third the GWP of conventional refrigerants currently used in room air conditioners.
In addition to adding these climate-friendly alternatives, the EPA also exempts all of these substances, except HFC-32, from the Clean Air Act prohibition of ventilation, as current evidence suggests that their ventilation, release, or disposal does not pose a threat to the environment.
