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Exemptions for Essential Uses of Chlorofluorocarbons for Metered-Dose Inhalers

Under the Montreal Protocol on Substances that Deplete the Ozone Layer, the production and consumption of most Class I ozone depleting substances (ODS) has been banned. However, the Parties to the Montreal Protocol provided an exemption for essential uses.

For a time, the United States received annual exemptions for chlorofluorocarbons for metered-dose inhalers (MDIs) used to treat asthma and chronic obstructive pulmonary disease. Today, all former essential uses have transitioned to ozone-safe alternatives. Additional information on the transition to ozone-safe MDIs can be found here:

The Clean Air ActHelpClean Air ActA law amended by Congress in 1990. Title VI of the CAA ( directs EPA to protect the ozone layer through several regulatory and voluntary programs. Sections within Title VI cover production of ozone-depleting substances (ODS), the recycling and handling of ODS, the evaluation of substitutes, and efforts to educate the public. still allows limited essential use exemptions if the Montreal Protocol criteria are met. Information on how to apply for an essential use exemption can be found in the Federal Register notice Protection of Stratospheric Ozone: Request for Applications for Essential Use Exemptions  (June 6, 2014, 79 FR 32728).

Montreal Protocol Essential Use Decision Criteria

A controlled substance qualifies as essential only if:

  1. It is necessary for the health and safety—or is critical for the functioning—of society (encompassing cultural and intellectual aspects).
  2. There are no available technically and economically feasible alternatives or substitutes that are acceptable from the standpoint of environment and health.

Production and consumption, if any, of a controlled substance for essential uses is permitted only if:

  1. All economically feasible steps have been taken to minimize the essential use and any associated emission of the controlled substance.
  2. The controlled substance is not available in sufficient quantity and quality from the existing stocks of banked or recycled controlled substances.