Clean Air Act (Caa) Definition

Clean Air Act (Caa)

The law that defines the United States Environmental Protection Agency's (EPA's) responsibility to protect and improve the nation's air quality and the stratospheric ozone layer. Among other things, the EPA regulates airborne contaminants, smog, and air pollution. The current Clean Air Act was passed in 1970 and significantly amended in 1977 and 1990.