|any of a class of chemical compounds derived from hydrocarbons by replacing one or more hydrogen atoms by bromine atoms and other hydrogen atoms by other halogen atoms (chlorine, fluorine, or iodine). Halons are stable compounds that are used in fire extinguishers, although they may contribute to depletion of the ozone layer|
|halon (hā'lŏn) Pronunciation Key
Any of several compounds consisting of one or two carbon atoms combined with bromine and one or more other halogens. Halons are gases and are used as fire-extinguishing agents. They are between three and ten times more destructive to the ozone layer than CFCs are.
chemical compound formerly used in firefighting. A halon may be any of a group of organohalogen compounds containing bromine and fluorine and one or two carbons. The effectiveness of halons in extinguishing fires arises from their action in interrupting chain reactions that propagate the combustion process. Halons are nonconductors of electricity and can be used in fighting fires in flammable liquids and most solid combustible materials, including those in electrical equipment; they are ineffective on fuels containing their own oxidizing agent or highly reactive metals, such as sodium or potassium. Halon 1301 (bromotrifluoromethane) is especially favoured for extinguishing fires involving electronic equipment because it leaves no residue and does not cause electrical short circuits or damaging corrosion of the equipment.
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