Fire extinguisher useful in fighting fires with a particular group of fuel. Specifications for fire extinguishers are set out in the standard AS/NZS 1841, the most recent version being released in 2007. All fire extinguishers must be painted signal red. Except for water extinguishers, each extinguisher has a coloured band near the top, covering at least 10% of the extinguisher's body length, specifying its contents. In Australia, yellow (Halon) fire extinguishers are illegal to own or use on a fire, unless an essential use exemption has been granted, this is due to the ozone-depleting nature of halon. According to the standard BS
Fire extinguisher gas that works by inhibiting the chain reaction of the fire and is the most toxic of the vaporizing liquids, used until the 1960s. The vapor and combustion by-products of all vaporizing liquids were highly toxic and could cause death in confined spaces. The carbon dioxide (CO) extinguisher was invented (at least in the US) by the Walter Kidde Company in 1924 in response to Bell Telephone's request for an electrically non-conductive chemical for extinguishing the previously difficult-to-extinguish fires in telephone switchboards. It consisted of a tall metal cylinder containing of CO with a wheel valve and a woven brass,