Clean Air Act

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Clean Air Act

United States [1990]

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Last updated

June 22, 2026

Quick Summary

The Clean Air Act (CAA) is a U.S. federal law enacted in 1970 and amended in 1990. Its primary goals are to prevent air pollution, protect the ozone layer, and promote public health. The act grants the Environmental Protection Agency (EPA) authority to regulate pollution.

Key aspects of the CAA include:
* National Ambient Air Quality Standards (NAAQS): These set limits for six major pollutants: sulfur dioxide, nitrogen dioxide, particulate matter, carbon monoxide, ozone, and lead. States must meet these standards or face penalties.
* New Source Performance Standards (NSPS): These regulate emissions from various industrial facilities.
* National Emissions Standards for Hazardous Air Pollutants (NESHAP): These address pollutants that pose risks to public health.
* Acid Rain Program: This market-based system aims to reduce sulfur dioxide emissions.
* Ozone Layer Protection: The act mandates the phasing out of substances like chlorofluorocarbons (CFCs) to protect the ozone layer.

The CAA has led to significant reductions in air pollution, improving public health and the environment.

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acid rain
History
…Act of 1970 and its amendments in 1990. Work toward developing a Memorandum of Intent between the U.S. and Canada to reduce air pollution and acid deposition began in the 1970s. However, it was not formalized until the Canada–United States Air Quality Agreement in 1991, which placed permanent caps on…
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…Act of 1970 and its amendments in 1990. Work toward developing a Memorandum of Intent between the U.S. and Canada to reduce air pollution and acid deposition began in the 1970s. However, it was not formalized until the Canada–United States Air Quality Agreement in 1991, which placed permanent caps on…
Read More

bituminous coal
…regulations stemming from the 1990 Clean Air Act, a growing number of coal-fired electric power plants in the United States have either installed cleaning devices to reduce air pollution emissions or switched to low-sulfur subbituminous coal. Some European countries have instituted similar measures, while others, such as France, have largely…
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…regulations stemming from the 1990 Clean Air Act, a growing number of coal-fired electric power plants in the United States have either installed cleaning devices to reduce air pollution emissions or switched to low-sulfur subbituminous coal. Some European countries have instituted similar measures, while others, such as France, have largely…
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Robert C. Byrd
… (1989–93) signed into law the Clean Air Act (1990), which threatened the livelihood of coal miners in his home state, Byrd worked to bring industry and federal jobs to West Virginia through his position as chairman of the Senate Appropriations Committee (1988–2008). He also provided needed guidance on procedural matters…
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… (1989–93) signed into law the Clean Air Act (1990), which threatened the livelihood of coal miners in his home state, Byrd worked to bring industry and federal jobs to West Virginia through his position as chairman of the Senate Appropriations Committee (1988–2008). He also provided needed guidance on procedural matters…
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environmental economics
Examples of regulation using corrective instruments
After the Clean Air Act Amendments of 1990, pollution taxes and permit markets became the preferred tools for environmental regulation. Although permit markets had been used in the United States as early as the 1970s, the Clean Air Act Amendments of 1990 ushered in an era of…
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After the Clean Air Act Amendments of 1990, pollution taxes and permit markets became the preferred tools for environmental regulation. Although permit markets had been used in the United States as early as the 1970s, the Clean Air Act Amendments of 1990 ushered in an era of…
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environmental law
Economic incentives
…as part of the 1990 Clean Air Act, was designed to reduce overall sulfur dioxide emissions by fossil-fuel-fired power plants. According to proponents, the program would provide financial rewards to cleaner plants, which could sell their unneeded credits on the market, and allow dirtier plants to stay in business while…
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…as part of the 1990 Clean Air Act, was designed to reduce overall sulfur dioxide emissions by fossil-fuel-fired power plants. According to proponents, the program would provide financial rewards to cleaner plants, which could sell their unneeded credits on the market, and allow dirtier plants to stay in business while…
Read More