CFC stands for compounds that are commonly referred to as chlorofluorocarbons, meaning they have chlorine, fluorine, and carbon chiefly as their molecular makeup. CFCs were used extensively as a refrigerant gas in the cooling and air conditioning industry. They went more commonly by the name "Freon" and "Freon-12" when in use by the DuPont Corporation. It was found in the 1970s that high CFC content in the atmosphere was contributing to degradation of the ozone layer in Earths stratosphere. The ozone layer is located in the stratosphere, which is the second layer of Earths atmosphere. The ozone layer absorbs most of the harmful cosmic radiation from the sun, and does not allow it to reach Earths surface. If the ozone layer were not in place, or not functioning as well as it does today, we would have to wear radiation suits just to go outside our houses and homes.