Donora Pennsylvania was hit by a smog on October 26 in 1948. The smog was caused by the smelting of zinc and melting of metals from plants.The people of Donora Pennsylvania were hit with a fog that trapped the pollutants from the zinc causing a thick white cloud which looked like fog. Soon after the 14,000 resident felt the effects of the smog. People with Pre-existing health conditions, mostly old people, started to die. People of Donora were in a panic trying to evacuate but was unsuccessful because of the smog being to thick for people to drive.Zinc works the company running the smelting plants in Donora finally decided to shut down the plants, this was a smart move because it improved the conditions. The Donora smog incident revived national news coverage people are more aware of air pollution in the United states. This also lead to the United States passing an act called the clean air act of 1955 which gave government funding to the research of air pollution in the U.S.A.