An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to www.epa.gov. This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Exemptions to the Phaseout

Certain ozone-depleting substances (ODSHelpODSA compound that contributes to stratospheric ozone depletion. ODS include chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), halons, methyl bromide, carbon tetrachloride, hydrobromofluorocarbons, chlorobromomethane, and methyl chloroform. ODS are generally very stable in the troposphere and only degrade under intense ultraviolet light in the stratosphere. When they break down, they release chlorine or bromine atoms, which then deplete ozone. A detailed list (http://www.epa.gov/ozone/science/ods/index.html) of class I and class II substances with their ODPs, GWPs, and CAS numbers are available.) used in specific applications are exempt from the phaseout rules and schedules. Authorized exemptions under the Montreal ProtocolHelpMontreal ProtocolThe international treaty governing the protection of stratospheric ozone. The Montreal Protocol on Substances That Deplete the Ozone Layer and its amendments control the phaseout of ODS production and use. Under the Montreal Protocol, several international organizations report on the science of ozone depletion, implement projects to help move away from ODS, and provide a forum for policy discussions. In addition, the Multilateral Fund provides resources to developing nations to promote the transition to ozone-safe technologies. The full text of the Montreal Protocol (http://ozone.unep.org/Publications/MP_Handbook/Section_1.1_The_Montreal_Protocol/) is available from the United Nations Environmental Programme (UNEP). include: