View source for Bromochlorodifluoromethane

{{chembox
| ImageFileL1 = Halon-1211-2D.png
| ImageSizeL1 = 112px
| ImageFileR1 = Halon-1211-3D-vdW.png
| ImageSizeR1 = 120px
| IUPACName = Bromochlorodifluoromethane
| OtherNames = Chlorodifluoromonobromomethane, Halon 1211, Halon 1211 BCF, BCF, Freon 12B1 
| Section1 = {{Chembox Identifiers
|   CASNo = 353-59-3
|   EINECS = 206-537-9
|   PubChem = 9625
|   SMILES = C(F)(F)(Cl)Br
|   InChI = 1/CBrClF2/c2-1(3,4)5
  }}
| Section2 = {{Chembox Properties
|   Formula = CBrClF<sub>2</sub>
|   MolarMass = 165.36 g/mol
|   Appearance = 
|   Density = 1.799 g/cm<sup>3</sup>
|   MeltingPt = −159.5 °C
|   BoilingPt = −3.7 °C
|   Solubility = 
  }}
| Section3 = {{Chembox Hazards
|   MainHazards = 
|   FlashPt = 
|   Autoignition = 
  }}
}}
'''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 [[carbon|C]][[fluorine|F]]<sub>2</sub>[[chlorine|Cl]][[bromine|Br]].  

Brominated haloalkanes were first used during World War II as [[fire extinguisher]] for aircraft and [[tank]]s. Bromochlorodifluoromethane was introduced as an effective [[gaseous fire suppression]] agent around 1973 for use around highly valuable materials in places such as [[museum]]s, [[Mainframe computer|mainframe]] rooms and telecommunication [[telephone exchange|switching centers]].  They were also widely used in the maritime industries in the engine rooms of ships.  Its efficiency as a fire extinguishing agent has also led it to be the predominant choice of fire extinguishing agent on commercial aircraft and is typically found in cylindrical hand-held canisters. Its advantages as a fire extinguishing agent are that it has lower toxicity than chemicals such as [[carbon tetrachloride]] and that since it is a [[Covalent bond|covalently bonded compound]], it does not form conductive ions which make it usable on electrical equipment. 

==Ozone depleting substance==
The production of bromochlorodifluoromethane and similar [[chlorofluorocarbon]]s has been [[Ban (law)|banned]] in most countries since January 1, 1994 as part of the [[Montreal Protocol]] on [[ozone layer|ozone]] depleting substances. However, recycling of halon 1211 allows it to remain in use, although parts availability is limited to a few manufacturers and can be an issue. Halon 1211 is still widely used in the United States, despite its high cost, with the US Military being the biggest user, but Europe and Australia have banned its use for all but "critical applications" such as aviation, military, and police use.

The manufacture of [[Underwriters' Laboratories|UL Listed]] halon 1211 extinguishers was supposed to stop October, 2009.  The future listing is still in discussion.  Halotron I is the replacement extinguishing agent.  It takes a larger volume to get the same ratings as 1211 has.

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

==See also==
*[[Bromotrifluoromethane]]
*[[Halon Ozone Depleting Potential]]

==References==
* George H. Tryon et al., "Fire Protection Handbook Thirteenth Edition 1969", National Fire Protection Association, Boston Massachusetts, 1969, Library of Congress 62-12655, no ISBN.
* Arthur E. Cote et al., "Fire Protection Handbook Eighteenth Edition", National Fire Protection Association, Quincy, Massachusetts, 1997, ISBN 0877653771

==External links==
*{{ICSC|0635|06}}
*{{INRS|title=Bromochlorodifluorométhane|number=165|year=1988}}
*[http://www.h3rcleanagents.com/support_faq_2.htm Basic Facts about Halon]
*[http://www.ansul.com/AnsulGetDoc.asp?FileID=13402 MSDS at ansul.com]
*[http://www.h3rcleanagents.com/support_faq_9.htm Recycling Halon]
*[http://www.h3raviation.com/support_faq_2.htm Aviation fire extinguisher requirements]

{{Halomethanes}}

[[Category:Halomethanes]]
[[Category:Fire suppression agents]]
[[Category:Greenhouse gases]]
[[Category:Air safety]]
[[Category:Organobromides]]
[[Category:Organochlorides]]
[[Category:Organofluorides]]

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