Clean Air Act
Updated: September 3, 2024The Clean Air Act (CAA) is a comprehensive federal law of the United States that regulates air emissions from stationary, mobile, and other air pollution sources, including greenhouse gases. Among many required statutory elements, it authorizes the Environmental Protection Agency (EPA) to establish National Ambient Air Quality Standards (NAAQS) to protect public health and welfare and to regulate emissions of hazardous pollutants. The CAA established detailed responsibilities of the individual states and EPA. Several acts and amendments were passed starting in 1963 that together form the basis of federal air quality administrative law regulations today, as well as extensive case law interpretations–the most recent amendments passed in 1990.