The original Fire Triangle showed oxygen, heat and fuel as the three components of fire. This fourth element (the chemical chain reaction) has been added to demonstrate how these three sources (oxygen, heat and fuel) interact to create fire. It’s this chain reaction process that creates the flames – the key to stopping fires is to stop this chain reaction from occurring.
But, what are the benefits of understanding the fire triangle/tetrahedron? And, is this something a fire warden should learn?
In short, yes. The idea behind the fire triangle/tetrahedron is that if you know how fires begin, it’s easier to grasp how to prevent and tackle fires.
The tetrahedron diagram works better than the triangle because it makes it clear how a fire extinguisher works.
Extinguishers work by creating a barrier between the fires components – fuel, heat and air – thus preventing the chemical chain reaction from happening.
To disrupt the elements that form the Fire Tetrahedron and thus put out the fire, you need to do one or more of these four things:
Remove fuel sources. This can be a preventative measure i.e. making sure potential fire hazards are stored safely or if a fire has started you can use water to disperse the fuel sources and to cool them.
Cool the burning materials with water.
Exclude oxygen. For example, with a fire blanket to prevent oxygen from reaching the process.
Break the chemical reaction. It is the chain reaction that keeps a fire going.
If you need to know more about what types of fire extinguishers are used to tackle specific classes of fire such as those needed for cooking oil fires or those involving flammable liquids, check out our guide to understanding fire extinguishers.