freon

thumb|A can of 1,1,1,2-Tetrafluoroethane (Freon 134a) used for recharging vehicle air conditioning Freon ( ) is a registered trademark of Chemours and generic descriptor for a number of halocarbon products. They are stable, nonflammable, low toxicity gases or liquids which have generally been used as refrigerants and as aerosol propellants. They include chlorofluorocarbons (CFCs) and hydrofluorocarbons (HFCs), both of which cause ozone depletion (although the latter much less so) and contribute to global warming. "Freon" is the brand name for the refrigerants R-12, R-13B1, R-22, R-410A, R-502, and R-503 manufactured by Chemours. They emit a strong smell similar to acetone. Freon has been found to cause damage to human health when inhaled in large amounts. Studies have been conducted in the pursuit to find beneficial reuses for gases under the Freon umbrella as an alternative to disposal.

==History== The first CFCs were synthesized by Frédéric Swarts in the 1890s. In the late 1920s, a research team was formed by Charles Franklin Kettering in General Motors to find a replacement for the dangerous refrigerants then in use, such as ammonia. The team was headed by Thomas Midgley Jr. In 1928, they improved the synthesis of CFCs and demonstrated their usefulness for such a purpose and their stability and nontoxicity. Kettering patented a refrigerating apparatus to use the gas; this was issued to Frigidaire, a wholly owned subsidiary of General Motors.