7,000 were hospitalized with respiratory problems. The cause was a weather anomaly that trapped toxic waste emissions from the town's zinc smelting plant close to the ground. The Donora disaster brought air pollution into focus in the United States, and paved the way for the Clean Air Act, enacted in 1963 and strengthened in 1970 .
Between December 5 and 9, 1952, 4,000 people died in London as a result of smog trapped in a thermal inversion (a condition where the air close to the ground is colder than the layer above it, and is therefore unable to rise above it). This incident brought about England's Clean Air Act in 1956 .
All around the world, the advent of the internal combustion engine-powered vehicles compounded air pollution, adding particulate and gaseous contaminate to the…show more content… Moreover, the local authorities were not obliged to declare their areas smoke control zones so the application of the Act to domestic smoke was left to the discretion of local authorities .
But, despite of all the above mentioned criticisms related to it the Clean Air Act 1956 has been viewed as a pioneering piece of legislation because, for the first time, it addressed the issue of controlling domestic as well as industrial smoke. As stated earlier also the Clean Air Act of 1968 was the follow-up to the Clean Air Act of 1956 which reduced pollution in the cities of England by creating smokeless zones, moving power plants out of the cities, and introducing cleaner burning fuels. The Act introduced the idea of using tall chimneys for industrial burning of coal and gaseous fuels because the legislation felt that the complete removal of sulphur dioxide was impossible. They therefore wanted to release the sulphur dioxide as high as possible to control the smoke pollution .