International efforts are on to save the ozone layer, which protects earth from ultraviolet (UV) radiations. UV rays are harmful to human health and several other life forms in water bodies. India has joined in this effort by signing the Montreal Protocol Treaty in 1992. It stipulates phasing out of CFCs including halons, being used in aerosol products, pressurized dispensers, domestic refrigerators, air-conditioners and fire extinguishers etc. Halon exhibit exceptional fire fighting characteristics and render the fire fighting operations neat and smooth. These have, therefore, found extensive usage as an agent in fire extinguishers/systems. Halons however possess high ozone depleting potential which is an environmental concern. Halons are fully halogenated chemicals that have relatively long life in the atmosphere, travel to stratosphere and are broken down by sunlight releasing bromine atoms which are very destructive to earth's protective ozone layer. Its global warming potential is also very high.
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