Clean Air Act The law that defines EPA's responsibilities for protecting and improving the nation's air quality and the stratospheric ozone layer. Draft Year: 1963 Amendment Years: 1965, 1970, 1990 Purpose: To control air pollution on a national level. Regulated and Enforced by: EPA

Amendments 1963 – funding for the study and the cleanup of air pollution – Amendment required the U.S. Department of Health, Education and Services to create and enforce auto emission standards – Congress passed a stronger CAA, which included a comprehensive federal response addressing air pollution.

1977 – Amendments required Prevention of Significant Deterioration (PSD) of air quality for areas attaining the NAAQS, and added requirements for non-attainment areas – Stricter and more cost-effective approaches to reduce air pollution.