Bromochlorodifluoromethane

Bromochlorodifluoromethane, also known by the trade name Halon 1211, or BCF, or Halon 1211 BCF, or Freon 12B1, is a haloalkane with the chemical formula is CF2ClBr.

Brominated halogens were first used during World War II as fire extinguisher for aircraft and tanks. Bromochlorodifluoromethane was introduced as an effective gaseous fire suppression agent around 1973 for use around highly valuable materials in places such as museums, mainframe rooms and telecommunication switching centers. They were also widely used in the maritime industries in the engine rooms of ships. Its advantages as a fire extinguishing agent was that it had lower toxicity than chemicals such as carbon tetrachloride and that since it was a covalently bonded compound, it did not form conductive ions which made it usable on electrical equipment.

The production of bromochlorodifluoromethane and similar chlorofluorocarbons has been banned in most countries since January 1, 1994 as part of the Montreal Protocol on ozone depleting substances.

This is a volatile extinguishant that should be used only with a breathing apparatus (when volume exceeds 5%).