Oh So Useful
Fire is a chemical reaction of fuel and oxygen in presence of heat. It is a chain reaction in which a minimum temperature is required which is called ignition temperature. But only fuel, heat and oxygen are not sufficient to catch fire unless chain reaction is not there. Fire is classified into four categories like class A-general fire, class B-oil fire, class C-gaseous fire and class D-metallic fire. There is another type of fire called electric fire which is nothing but a general fire when electric supply is switched off. There are many types of water fire extinguishers like foam type e.g. 9 liter Aqueous Film Forming Foam(AFFF) used for general and oil fire, Dry Chemical Powder used for metallic fire, Carbon dioxide used for electric fire, water, fire bitter, sand, fire blanket etc. Fire should be controlled it its initial stage otherwise it is very difficult to extinguish in later stage. There are many government and non government fire fighting agencies in the country.