Although laws had been enacted prior to the Clean Air Act (CCA) of 1970, none were as comprehensive in the regulation of air pollution from stationary (industrial) and mobile sources (cars, trucks, and planes). Major amendments to the CAA were made in 1977 and 1990.
The current CAA includes four basic programs: the National Ambient Air Quality Standards (to control six principle air pollutants, including ozone, nitrogen dioxide, particulate matter, and lead), National Emission Standards for Hazardous Air Pollutants (to control the release of 189 known toxins), New Source Performance Standards (to regulate new sources of industrial pollution), and State Implementation Plans (authorizing each state to implement CAA laws).
At the same time, the National Environmental Policy Act was enacted to create the U.S. Environmental Protection Agency and authorize the agency to implement the many requirements included in the Clean Air Act of 1970.
In addition, and particularly important to the work of NELC, the Clean Air Act authorizes the public to bring citizen suits against companies who violate the law when state and federal agencies fail to act.
Texas Senator Ralph Yarborough speaking to the Senate as they debate the Clean Air Act of 1970:
"We can no longer afford to allow millions of tons of contamination to be dumped into our atmosphere year after year by automobile and industry emissions. We hear many suggestions that this legislation establishes a goal, the achievement of which is beyond the capacity of American technology. I do not believe that we lack the ability to come up with the answers to the dilemma which confronts us. Certainly, the gravity of the challenge should not deter us from action."
S. 4358 Senate Debate, Sept. 22, 1970 (statement of Sen. Yarborough),reprinted in Comm. on Pub. Works, 93rd Cong., Legislative History of the Clean Air Amendments of 1970, at 394-95 (1974).