An Act of the UK Parliament introduced in 1956 to reduce the level of air pollution, in particular, by controlling the use of coal as a heating medium in homes. The Act was a major landmark in environmental protection in the UK and was responsible for reducing the level of smoke pollution as well as harmful sulphur dioxide emitted from domestic fireplaces into the environment. The Act was also responsible for the relocation of power stations away from urban areas, and also included an increase in the height of chimneys for more effective dispersion of emissions. The Act was amended in 1993.

In the US, the Clean Air Act was introduced in 1963 as a federal law to control air pollution. The Environmental Protection Agency is responsible for enforcing the regulations and for protecting the public from airborne contaminants that are hazardous to health arising from domestic and industrial sources. There have been subsequent amendments to the Act, particularly to address airborne pollution such as acid rain and effects of ozone depletion.

http://www.legislation.gov.uk/ukpga/1993/11/contents Official website of HM Government managed by the National Archives to publish all enacted legislation in the UK.