Class I substance

A Class I substance is one of several groups of chemicals given an ozone-depletion potential (ODP) of 0.2 or higher by the Environmental Protection Agency (EPA).

Class I substances listed in the Clean Air Act include chlorofluorocarbons, halons, carbon tetrachloride, and methyl chloroform.

The EPA later added HBFCs and methyl bromide to the list by regulation.

## External links[edit]

* Table of class I substances shows their lifetime ODPs, global warming potentials, and CAS numbers.