Firefighting – are we being sold a duff theory?

Any of you who have received any training in fighting fires will be familiar with the term ‘the fire triangle’. For those who aren’t, this is a triangle where each side represents the 3 items required to make fire, i.e. fuel, heat and oxygen. The idea of the triangle is that removal of one item breaks the triangle and it becomes imcomplete in the same way that removal of one item puts out a fire.

This theory has been the basis of fire training (at least within the airlines) for many years, however for the last year or so I have been challenging the thinking with no one yet capable of offering me a satisfactory answer.

Here’s what is taught –
1) In the event of a fire, smothering with a blanket will put out the flames. This is the example of removal of OXYGEN.
2) In an engine fire, the fire may be extinguished by turning off the supply cocks. This is the example of removal of the FUEL.
3) In a non-electrical (and certain non-chemical) fire water will put out the fire. This is the example of removing the HEAT.

It is this third situation that I have a problem with. In my view the actual occurence here is not that water cools a fire but changes the fuels nature into that of a cr@p combustor. If water was putting the fire out by cooling it then the following logic must apply – the water is liquid so it must be above 0 degrees C. In that case it is impossible to light a fire in sub-zero conditions. This is obviously not true, a match can be lit at the poles (as long as it isn’t too windy!). Conversely according to this theory, applying a hot jet of steam to a fire would not extinguish it. I think the actual result in case 3 is that adding the water to the fuel (say for example a piece of wood) causes the wood to be a poor fuel which is why the fire goes out. It doesn’t go out because the fire was cooled.

So can anyone prove the ‘fire triangle’ theory and tell me how you can remove the heat from a fire in order to put it out?