The Clean Air Act is the federal law designed to make sure that all Americans have air that is safe to breathe. Public health protection is the primary goal, though the law also seeks to protect our environment from damage caused by air pollution.
The Clean Air Act requires that the U.S. Environmental Protection Agency set national health-based air quality standards to protect against common pollutants including ozone (smog), carbon monoxide, sulfur dioxide, nitrogen dioxide, lead, and particulate soot. State governments must devise cleanup plans to meet the heath standards by a specific date. (Areas with the worst smog have a longer time to meet the standards.) In addition, the EPA sets national standards for major new sources of pollution including automobiles, trucks and electric power plants. The agency also is charged with developing controls for major sources of such toxic pollutants as benzene.
Congress passed the core provisions of the Clean Air Act in 1970. The law was amended in 1977 and again in 1990 to extend deadlines but also to specify new strategies for cleaning up the air. The basic framework of the law and its public health objective have remained intact.
By any objective measurement, the act has been a tremendous success. The air is cleaner and public health has improved. Emissions of toxic lead have dropped 98 percent. Emissions of sulfur dioxide have dropped by 35 percent percent even though the gross domestic product has more than doubled. Emissions of carbon monoxide have dropped by 32 percent even though driving has increased 127 percent. Even so, many areas of the country still violate the basic health standards, and the health of tens of millions of Americans remains at risk.