adminFire is a chemical reaction which involves a combination of a burning material and oxygen started by heat. That is to say for a fire to take place heat, fuel and oxygen should be always present. Therefore the ways used to extinguish fires involve removal of one or more of these elements.
COOLING
Cooling is the removal of heat. This is by far the mostly used method of extinguishing fire. Water is the readily available coolant to use especially on fires involving solid materials. The water will absorb heat from the fire and a result the fire will go out. However, water should never be used on fires involving live electrical equipment and on flammable liquids.
SMOTHERING
Smothering is a way of excluding oxygen from the fire. There are many agents such as foam which can cut off oxygen supply to the fire. Foam when applied on a fire, forms a blanket over the burning material thereby cutting off oxygen supply.
Since over three quarters of foam is water, never use foam on energized electrical equipment. Other smothering agents include carbon-dioxide which is found in black fire extinguishers.
STARVATION
The third method of extinguishing fires is to remove the fuel. This could be done by isolating the fuel supply, for example, cutting the flow of gas or removing solid fuels. In woodlands, constructing a fire break isolate burning material.
There are other substances that chemically react with the burning material thus extinguishing the flame.
Dry chemical powders extinguishes fire this way by inhibiting the flame.
Vaporising liquids also have a flame inhibiting action, but because of their high toxicity most of them have been phased out.
Online Reporter