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Overview of the Clean Air Act and Air Pollution

The United States has made great progress since 1970 in cleaning the air, but the job is far from complete. November 15, 1990 marks a milestone in Clean Air Act history, the signing of the 1990 Amendments. These amendments set the stage for protecting the ozone layer, reducing acid rain and toxic pollutants, and improving air quality and visibility.

Overview of the Clean Air Act and Air Pollution

How the Act Works:

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 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>

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>

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>

Flexibility and Accountability

Under the Act, EPA seeks to provide industry with flexibility on ways to control emissions while maintaining accountability for achieving reductions. <Learn more about building flexibility and accountability into CAA programs>

Clean Air and the Economy

Over forty 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 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.

2019 Air Emissions Graph Showing Decline of Key Pollutants

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

Air Pollution Challenges:

Despite the dramatic progress to date, air pollution continues to threaten Americans’ health and welfare.

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