Official name: Clean Air Act
Citation: 42 U.S.C. § 7401 et seq. (1970; major amendments 1977 and 1990)
Year / status: Enacted 1970. Still in force, with later amendments.
What it does
The Act requires national ambient air-quality standards, state implementation plans, permits for new and modified sources, mobile-source controls, and: after 1990: an acid-rain cap-and-trade programme and tighter toxics rules. It is a pollution statute, not a comprehensive climate law, though some greenhouse-gas rules have been built on it.
Where it applies / status
United States federal law, implemented by EPA and by the states. It does not apply outside U.S. jurisdiction.
Documented benefits or intended effects
EPA’s Second Prospective study (2011), required by Section 812 of the 1990 amendments, estimated that those amendments would prevent about 230,000 premature deaths in the year 2020 and that the central benefits estimate exceeded costs by more than 30 to 1. Those figures are model results against a no-amendment baseline, not a count of named people.
Caveats
Benefits are estimated, not observed one-for-one. Some areas still miss standards. Litigation and political cycles change rules. Do not treat the Act as a finished climate instrument or as proof that every local airshed is clean.
Sources
EPA Clean Air Act overview; EPA “Benefits and Costs of the Clean Air Act 1990-2020, the Second Prospective Study”; U.S. Code chapter 85.