Far-reaching environmental legislation continues to change the way Americans live, work, and run their businesses. For the past decade and a half, companies have worked toward meeting the latest air quality standards set by the Environmental Protection Agency (EPA).

In 2005, regulations introduced by the Clean Air Act of 1990 came into full effect with the goal of reducing harmful emissions by 57-billion pounds per year. The act continues to have a huge impact both economically and environmentally as it targets the sources of urban air pollution, acid rain, and stratospheric ozone depletion.

Air pollution is not a new problem in the United States. During the 1940s, a series of pollution-related disasters forced Americans to acknowledge the need for clean air standards. The worst of those incidents took place during a five day period in 1948, when smog caused by industrial emissions and coal-burning furnaces killed 20 people and sickened nearly 7,000 others in the small town of Donora, Pennsylvania.

The tragedy spurred the federal government to take control of air quality management. In 1955, the Air Pollution Control Act was introduced to mandate the national investigation of air pollution. More stringent air quality controls were later established with the creation of the Clean Air Act of 1970 and the formation of the EPA. In 1990, the Clean Air Act was revised to include the following amendments: