The Clean Air Act (CAA) wasn’t the first major change in the regulatory environment. Today, we would like to look at a bit of background, sharing the demands for increased pollution controls in the 40s and 50s, and the move to write the Clean Air Act in 1963, before major changes in 1970.

The Clean Air Act traces its roots back to the Air Pollution Control Act of 1955, signed into law by the Eisenhower Administration, and the Clean Air Act of 1963 and Air Quality Act of 1967, both signed into law by the Johnson Administration. However, the act and pursuant regulations trace back millennia, as discussed in our last article, [link]Know the Playing Field: Air Pollution Laws and Regulations from AD 0 to 1950.[link]

The 1950s Created a Need for Pollution Controls

Following World War II, soldiers returned to the United States, the economy and population boomed, and the move toward urbanization and suburban living combined to create a pollution nightmare. The calls to control air pollution returned, as no longer was the civic duty of residents to tolerate pollution to support the war efforts in the Pacific and Europe.

The calls for additional oversight were driven by noteworthy events in the first half of the 20th Century including a period of near zero visibility in St. Louis in 1939, serious smog incidents in Los Angeles in the late 40s, an air pollution inversion event in Donora, PA that killed 40, and three incidents in New York City: a smog incident killing 170-260 and two air inversions killing 405 and 168, among others.

As cities, counties, and states moved to implement pollution controls, there was increasing pressure on Washington, D.C. to make something happen. This set forth a chain of events over the next few decades that changed the regulatory landscape starting in 1955.

Air Pollution Control Act of 1955

Touted as the first federal legislation involving air pollution, the Air Pollution Control Act was a non-regulatory bill that approved Federal spending on air pollution control research. Spanning only three pages, the bill was straightforward and established the federal government as having preeminent control over air pollution control matters. The bill was approved and signed into law, with amendments to continue funding in 1960 and expand the scope of research in 1962. You can read the entire text of the bill here.

Clean Air Act of 1963

The first legislation to include the term “Clean Air Act” was passed and signed into law in 1963, and set forth additional funding for education, research, and the creation of standards. Approved in December 1963, this legislation approved $95 million to state and local governments conduct research and conduct control studies. Amendments over the next seven years laid the groundwork for the Act of 1970:

  • Amendments of 1965 (Motor Vehicle Air Pollution Control Act): Worked to establish standards for automobile emissions. Promoted research into the effects of emissions on Canada and Mexico.
  • Amendments of 1966: Expanded local air pollution control programs.
  • Amendments of 1969: Extended authorization for research on low emissions fuels and automobiles.

Amendments of 1967 (Air Quality Act)

Immensely important to the 1970 Act, the Air Quality Act was the first step in setting regulations. This act:

  • Divided parts of the nation into Air Quality Control Regions for the purpose of monitoring ambient air
  • Established national emissions standards for stationary sources (contested until the establishment of industry standards)
  • Set timetables for State Implementation Plans, a major part of the 1970 Clean Air Act.

By 1969, all 50 states had passed legislation to implement some form of air pollution controls. The Journal of the Air Pollution Control Association explores the passage of state laws in their January 1982 issue, and we will discuss State Implementation Plans in an Upcoming Blog.

Ultimately, the AQA, while ambitious in nature, failed due to the lack of enforcement provisions.

The Clean Air Act of 1970

While technically a rewrite of the 1963 Act, the 1970 Act still exists as the act we know today (with major amendments in 1977 and 1990). Passed during a wave of environmentalism sweeping the nation, the Clean Air Act of 1970 was highly ambitious, highly complex, and set out to enforce standards.

The House Version passed by a vote of 375-1 in June 1970, and the slightly more stringent Senate Bill passed 73-0 in September. The reconciliation process was subject to lobbying—both from industry and President Nixon—but ultimately the bill passed and was signed into law on December 31, 1970.

EPA Gives CAA Legs on Which to Stand

Paired with the National Environmental Policy Act (the law creating the Environmental Protection Agency), the federal government now had two critical components of a federal program: Regulations and an Agency to enforce the Regulations.

New Source Performance Standards (NSPS)

New Source Pollution Standards (NSPS) were another major factor of the CAA of 1970. Setting more stringent standards for any new stationary source, the Act provided that new sources can and should be designed with the newest and most advanced technology.

National Ambient Air Quality Standards (NAAQS)

The CAA of 1970 requires the EPA to establish National Ambient Air Quality Standards (NAAQS) for air pollutants that endanger public health or welfare. Under the 1970 Act, NAAQS were set for six “criteria” pollutants, discussed below.

“Criteria” Pollutants

“Criteria” pollutants were among the most hazardous high volume pollutants that existed. The list of “criteria” pollutants (airborne particulates, sulfur oxide, nitrogen oxide, ozone, and lead) set the framework for a later focus—Hazardous Air Pollutants. The CAA allows the EPA to revise the list of pollutants, which led to the list of 188 as defined in 1990.

State Implementation Plans (SIPs)

While the Act authorizes the EPA to set NAAQS, the states are responsible for establishing procedures to attain and maintain the standards. SIPs take on current emissions amounts for their locale, determining where violations are likely to occur. From here, the EPA sets a minimum and the states can adopt standards meeting or exceeding the standards. We will discuss state implementation plans at a later date.


For the past 2000 years, there have been legal battles and regulations in place designed to reduce air pollution. While not as strict as those levied by King Edward I in 1306, noncompliance with current standards could not only lead to fines and other penalties, it could lead to lawsuits from affected persons, distrust from the community, and lost business. Simply put, taking control of your emissions isn’t just smart in terms of compliance, it’s just good business.

While it’s obvious that we can’t cover the entirety of any of these laws or regulations, we hope this scratches the surface and peaks your interest. In our next article, we will take a deeper look at the Clean Air Act Amendments of 1977 and 1990 in addition to smaller amendments pertaining. Learn more about HAP and VOC Abatement Tactics and Strategies, success stories, and tools used to fight pollution by contacting The CMM Group.

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