Learn how air pollution can harm your health and the environment, and what EPA is doing to protect the air we breathe.

The Earth’s ozone layer protects all life from the sun’s harmful radiation, but human activities have damaged this shield.

This page provides information on compounds recognized as ozone-depleting substances (ODS) under the Montreal Protocol.

The Atmospheric and Health Effects Framework (AHEF) model is used by the EPA to evaluate human health effects associated with a depleted stratospheric ozone layer.

As part of the United States’ commitment to implementing the Montreal Protocol on Substances that Deplete the Ozone Layer, Congress amended the Clean Air Act to add provisions (under Title VI) for protecting the ozone layer.