Significant New Alternatives Policy (SNAP) Program

Significant New Alternatives Policy (SNAP) Program

Class I Substance: one of several groups of chemicals with an ozone-depletion potential of 0.2 or higher

Class I substances listed in the Clean Air Act (CAA) include CFCs, halons, carbon tetrachloride, and methyl chloroform. EPA later added HBFCs and methyl bromide to the list by regulation. A table of class I substances shows their lifetime ODPs, GWPs, and CAS numbers.

Class II Substance: a chemical with an ozone-depletion potential of less than 0.2

Currently, all of the HCFCs are class II substances. Lists of class II substances with their ODPs, GWPs, and CAS numbers are available.

Federal Agencies

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Click here for more information on reducing hydrofluorocarbon (HFC) use and emissions in the Federal Sector.

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