The Fire Triangle
Generally, a fire needs three things to burn:
Fuel - something to bum, e.g.oi1.
Oxygen - to maintain combustion.
Ignition - something to start the fire, e.g. excessive heat, electrical spark, etc. This principle can be depicted in the form of a triangle as shown in Figure.
Figure: The fire triangle.
By removing any one of the three sides of the triangle, fire is prevented. For example, many fires obtain oxygen from the air where it is about 20% by volume. Fire extinguishers, e.g. sand or foam (subsection 12.4.2), prevent oxygen being available to the fuel or ignition source. Although air is the most common source of oxygen, other sources are,
- chlorates
- permanganates
- nitrates
- peroxides
- dichromates
- other oxidising agents
The essence of fire prevention is to prevent the formation of fire triangle.
With air containing oxygen all around us, this consists primarily of keeping fuel and ignition sources apart.