Method of Extension and Prevention:
Fire depends upon a reaction between two substance and continuous because of self generated heat. There are four ways of Extinguishing fire i.e., by cooling the fuel below its ignition temperature. By cutting off the oxygen, by cutting off the supply of fuel or by prohibiting the formation of chain carriers.
This is achieved by -
- Taking away the heat faster heat it is generated.
- Separating the substance apart.
- Cooling the combustible material and its surrounding to a temperature search that fire die for want to heat.
- Smoothing the fire by preventing air from reaching eat or by diluting air with some inert gas ( smothering ).
- Starving the fire by removing combustible material fuel supply.
What are the Methods of Fire Extinguishing:
- COOLING METHOD:
Extinction by cooling is achieve, when the rate of heat generated is less than the rate the heat remove, hence the fire die water is an excellent cooling agent and is Alos available in penalty all around sea. It first observed the heat from the surrounding/ fire, than it required rise to boiling point and on further absorption of heat corporate ( using latent heat of vaporization ).
It has a few limitation/disadvantages too such as excess of water application has stability hazards, liquid fuels float on water. Hence a major oil fire is unlikely to be put off by water seawater may cause severe damage of the electrical machinery. The water thus can be used after properly protecting the machineries in either of the following modes :-
(A) As a Jet:
It can be used for structural fire and fire involving solid. It can be Jet lined on the fire from a considerable distance. In addition to cooling and smoothing effects, it produce a floating effect which will separate a small flame from its fuel.
(B) As a Spray:
If the water is broken up to into very fine particles it covers a large surface area and heat transfer is very fast. It also protects the fire fighters from any radiated heat.
- SMOOTHENING METHOD:
It is the process of cutting of the air/oxygen supply to the existing fire. Attempt to smother a fire would be ineffective, if all the air required for complete combustion is intimately mixed with the fuel as in case of an explosive and Alos, if combustible materials are containing oxygen in it, ( e.g. tentiale, wood ). Liquid fuels normally do not contain oxygen
Foam is used to blanket the surface of the fuel and separate it from air. It can be produced mechanically from water, air and foam a compound or may be chemically produce.
Your oxygen can also be cut off by using gas or vapour which is inactive such as inert CO or dry chemical powder ( NaH CO3 ).
Basic Smoothering Agents:
Some of the Smoothering Agents are as follow below:
- Foam
- CO2
- Steam dreanching
- Vaporizing liquid ( Halon )
- Liquid chemical
- Sand
- Blanket
- STARVING METHOD:
This can be achieved :
- removing combustible material from the neighbourhood of fire drainage of fuel from Burning oil tanks.
- removing the fire from the neighbourhood of combustible Material by pulling apart burning version of fear.
- Sub-dividing the burning material and then exiting using small fires.
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