Fire Hazards of Freon Gasby Nida Rasheed
Freon is a liquid/gaseous chemical compound commonly used in refrigerators, air conditioners, and freezers. Known by the chemical name chlorodifloromethane, it is a nontoxic and nonflammable material. Although freon does not burn at room temperature, it may combust when mixed with air (65 percent) at low pressure. Concentrations of chlorine may also induce combustion in chlorodifloromethane.
Freon poses a negligible fire hazard when it is directly exposed to heat or flames, but chlorides, fluorides, and phosgene are released as a result of the thermal decomposition of the gas. Notably, phosgene is a poisonous gas and poses a serious threat to health.
Freon is used as a refrigerant in car air conditioning systems, and older models have the R-12 variety of the gas. If such a car catches fire, it is important not to inhale the fumes because the R-12 will turn into phosgene (nerve gas), a lethal chemical.
Freon is compressed into self-pressure-releasing cylinders that may rupture because of extended exposure to fires over 900 degrees Celsius. Freon itself does not catch fire, but the cylinders containing the gas may explode if the fire is not controlled. This happens because of pressure buildup within the cylinders caused by the rise in surrounding temperature. The shards of a bursting cylinder pose a serious hazard.
Freon cylinders should be stored at room temperature to avoid accidental overheating of contents. If water is used for extinguishing a fire, it should be contained and neutralized before it is disposed. Use a self-contained breathing apparatus (SCBA) if the containers have leaked or have been damaged within an enclosed space. Inhaling freon poses a serious hazard to health, and exposure to higher concentrations of the gas can be fatal.
- the fire extinguisher image by Oleg Guryanov from Fotolia.com