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Overview of the Clean Air Act and Air Pollution

  • The Clean Air Act Text

    The Clean Air Act is the law that defines EPA's responsibilities for protecting and improving the nation's air quality and the stratospheric ozone layer.

    Read the Clean Air Act
  • Celebrating the Clean Air Act Amendments of 1990

    On November 15, 1990, the Clean Air Act was revised to curb four major threats to the environment and to the health of millions of Americans: acid rain, urban air pollution, toxic air emissions, and stratospheric ozone depletion. The amendments also established a national operating permits program and strengthened enforcement to help ensure better compliance with the Act.
    Read the amendments
  • Clean Air Excellence Awards

    The Clean Air Excellence Awards Program periodically recognizes and honors outstanding innovative efforts to help make progress in achieving cleaner air.

    Explore the Clean Air Excellence Awards
  • Air Pollution: Current and Future Challenges

    Despite dramatic progress cleaning the air since 1970, air pollution in the United States continues to harm people’s health and the environment.

    Read about the challenges

The Act calls for states and EPA to solve multiple air pollution problems through programs based on the latest science and technology information.

  • Requirements and History

    Congress designed the Clean Air Act to combat a variety of air pollution problems, and to tackle emerging pollution threats.

    Learn more about CAA requirements and history
  • Role of State, Local, Tribal and Federal Governments

    The Clean Air Act calls for state, local, tribal and federal governments to work in partnership to clean the air.

    Learn more about the partnership among governments
  • Flexibility and Accountability

    Under the Act, EPA seeks to provide industry with flexibility on ways to control emissions while maintaining accountability for achieving reductions.

    Read about building flexibility and accountability into CAA programs
  • Role of Science and Technology

    Under the Clean Air Act, health-based air quality standards are based on the latest science. Emissions standards for sources are based on information about available technologies.

    Learn more about solving problems with science and technology
  • Public Participation

    Stakeholders and the public play critical roles in developing standards and implementation of the Clean Air Act.

    Learn more about developing programs through dialogue
  • Clean Air and the Economy

    Over 40 years of experience with the Clean Air Act shows that clean air and a healthy economy can go hand in hand. 

    Learn more about clean air and the economy

 Progress Cleaning the Air

Actions to implement the Clean Air Act have achieved dramatic reductions in air pollution, preventing hundreds of thousands of cases of serious health effects each year.

  • Accomplishments Under the Clean Air Act

2019 Air Emissions Graph Showing Decline of Key Pollutants

Since 1990 there has been approximately a 50% decline emissions of key air pollutants.

All Clean Air Topics

  • Learn About Air
  • Studies of Clean Air Act Benefits and Costs
  • Explore the Clean Air Excellence Awards
  • Clean Air Act Advisory Committee
  • Conventional Air Pollution
  • Ozone Layer Depletion
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on March 10, 2025
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