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Clean Air Act Overview

Evolution of the Clean Air Act

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Introduction

The legal authority for federal programs regarding air pollution control is based on the 1990 Clean Air Act Amendments (1990 CAAA). These are the latest in a series of amendments made to the Clean Air Act (CAA). This legislation modified and extended federal legal authority provided by the earlier Clean Air Acts of 1963 and 1970.

The Air Pollution Control Act of 1955 was the first federal legislation involving air pollution. This Act provided funds for federal research in air pollution. The Clean Air Act of 1963 was the first federal legislation regarding air pollution control. It established a federal program within the U.S. Public Health Service and authorized research into techniques for monitoring and controlling air pollution. In 1967, the Air Quality Act was enacted in order to expand federal government activities. In accordance with this law, enforcement proceedings were initiated in areas subject to interstate air pollution transport. As part of these proceedings, the federal government for the first time conducted extensive ambient monitoring studies and stationary source inspections.

The Air Quality Act of 1967 also authorized expanded studies of air pollutant emission inventories, ambient monitoring techniques, and control techniques.

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Clean Air Act of 1970

The enactment of the Clean Air Act of 1970 (1970 CAA) resulted in a major shift in the federal government's role in air pollution control. This legislation authorized the development of comprehensive federal and state regulations to limit emissions from both stationary (industrial) sources and mobile sources. Four major regulatory programs affecting stationary sources were initiated: the National Ambient Air Quality Standards (NAAQS, pronounced "knacks"), State Implementation Plans (SIPs), New Source Performance Standards (NSPS), and National Emission Standards for Hazardous Air Pollutants (NESHAPs). Furthermore, the enforcement authority was substantially expanded. The adoption of this very important legislation occurred at approximately the same time as the National Environmental Policy Act that established the U.S. Environmental Protection Agency (EPA). The EPA was created on December 2, 1970 in order to implement the various requirements included in these Acts.

For articles and press releases see:

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Clean Air Act Amendments of 1977

Major amendments were added to the Clean Air Act in 1977 (1977 CAAA). The 1977 Amendments primarily concerned provisions for the Prevention of Significant Deterioration (PSD) of air quality in areas attaining the NAAQS. The 1977 CAAA also contained requirements pertaining to sources in non-attainment areas for NAAQS. A non-attainment area is a geographic area that does not meet one or more of the federal air quality standards. Both of these 1977 CAAA established major permit review requirements to ensure attainment and maintenance of the NAAQS.

For articles and press releases see:

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Clean Air Act Amendments of 1990

Another set of major amendments to the Clean Air Act occurred in 1990 (1990 CAAA). The 1990 CAAA substantially increased the authority and responsibility of the federal government. New regulatory programs were authorized for control of acid deposition (acid rain) and for the issuance of stationary source operating permits. The NESHAPs were incorporated into a greatly expanded program for controlling toxic air pollutants. The provisions for attainment and maintenance of NAAQS were substantially modified and expanded. Other revisions included provisions regarding stratospheric ozone protection, increased enforcement authority, and expanded research programs.

For articles and press releases see:

EPA History: Clean Air Act Amendments of 1990

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Milestones

Some principal milestones in the evolution of the Clean Air Act are:

The Air Pollution Control Act of 1955

  • First federal air pollution legislation
  • Funded research for scope and sources of air pollution

Clean Air Act of 1963

  • Authorized the development of a national program to address air pollution related environmental problems
  • Authorized research into techniques to minimize air pollution

Air Quality Act of 1967

  • Authorized enforcement procedures for air pollution problems involving interstate transport of pollutants
  • Authorized expanded research activities

Clean Air Act 1970

  • Authorized the establishment of National Ambient Air Quality Standards
  • Established requirements for State Implementation Plans to achieve the National Ambient Air Quality Standards
  • Authorized the establishment of New Source Performance Standards for new and modified stationary sources
  • Authorized the establishment of National Emission Standards for Hazardous Air Pollutants
  • Increased enforcement authority
  • Authorized requirements for control of motor vehicle emissions

1977 Amendments to the Clean Air Act of 1970

  • Authorized provisions related to the Prevention of Significant Deterioration
  • Authorized provisions relating to areas which are non-attainment with respect to the National Ambient Air Quality Standards

1990 Amendments to the Clean Air Act of 1970

  • Authorized programs for Acid Deposition Control
  • Authorized a program to control 189 toxic pollutants, including those previously regulated by the National Emission Standards for Hazardous Air Pollutants
  • Established permit program requirements
  • Expanded and modified provisions concerning the attainment of National Ambient Air Quality Standards
  • Expanded and modified enforcement authority
  • Established a program to phase out the use of chemicals that deplete the ozone layer.

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