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Home > Resources > Fire Safety > How Fires Start

The Science behind it

Fire is a chemical reaction involving rapid oxidation or burning of a fuel. It needs three elements to occur:


Fuel can be any combustible material; solid, liquid or gas. Most solids and liquids become a vapor or gas before they will burn.


The air we breathe is about 21 percent oxygen. Fire only needs an atmosphere with at least 16 percent oxygen


Heat is the energy necessary to increase the temperature of the fuel to a point where sufficient vapors are given off for ignition to occur.


A chain reaction can occur when three elements of fire are present in the proper conditions and proportions. Fire occurs when this rapid oxidation, or burning takes place.

Take any one of these factors away, and the fire cannot occur or will be extinguished if it was already burning.