In line with previous iterations of the SNAP program, the EPA has expanded the list of acceptable alternatives for certain end-uses with its Final Rule 21, in December of 2016 to reduce the risk to human health and the environment.
The Significant New Alternatives Policy (SNAP) by the Environmental Protection Agency (EPA) of the United States provides a list of alternatives to the widespread ozone-depleting and polluting substitutes which were commonly used in the refrigeration industry. Following the Montreal Protocol, the use of CFCs was prohibited since 1989. Additionally, the Kyoto Protocol declared the reduction of HCFCs in 1997. The SNAP program is a part of the Climate Action Plan and makes decisions based on the overall understanding of the environmental and human health impacts as well as its current knowledge about available substitutes. Part of the policy is also the obligation to prohibit the use of a substitute where EPA did find a suitable replacement.
The SNAP program is designed to:
- Identify and evaluate substitutes in end-uses that have historically used ozone-depleting substances (ODS)
- Look at overall risk to human health and the environment of both existing and new substitutes
- Publish lists of acceptable and unacceptable substitutes by end-use
- Promote the use of acceptable substitutes
- Provide the public with information about the potential environmental and human health impacts of substitutes.
(Source: Environmental Protection Agency)
Propane Gaining Further Ground
As one of the last actions of the Obama administration, the SNAP program made a final step to reduce risk to human health and the environment by updating the list of effected end-uses. The latest version of SNAP includes a major step for the industry as the flammable hydrocarbon propane (R-290) is now listed as acceptable in more applications like self-contained commercial ice machines, water coolers, and very low-temperature refrigeration equipment. In addition, EPA exempted propane from venting prohibition under the Clean Air Act (CAA) section 608; thereby confirming that propane does not pose a threat to the environment, because of the relatively minimal air quality impacts of R-290. Even in the worst-case scenario, propane does not have a greater overall impact on human health and the environment in comparison to other refrigerants, which are listed as acceptable for commercial ice machines, water coolers, and very low-temperature refrigeration equipment.
Propylene and R-443A Still Listed As Unacceptable
In the same rule, the EPA also listed propylene (R-1270) as well as the blended refrigerant R-443A as unacceptable alternatives for new cold storage warehouses, where leakage of cooling systems is a big problem. The reason behind this listing lies neither in ozone depletion nor in its global warming potential. In addition to these two factors, the EPA also evaluates the potential impacts of propylene and the three components of R-443A on local air quality. The photochemical reactivity of propylene, which is also one of the three components of R-443A, is much higher than that of the other two HCs. That means that propylene as an unsaturated molecule is significantly more reactive in the atmosphere than propane, for example.
According to the latest releases of the EPA, the listing status for several refrigeration appliances will change in the future. As of the beginning of 2023, the most commonly used refrigerants for new cold storage warehouses will be listed as unacceptable. For new retail food refrigeration, refrigerated food processing and dispensing equipment as well as new household refrigerators and freezers, the same 2003 formulation will be listed as unacceptable as of January 1, 2021. For household applications, the refrigerants RS-24, SP34E, and THR-03 will be additionally listed as unacceptable.
- Market and Policy Trends for Natural Refrigerant Technology Around the World PDF download (5.15 MB)