Why can't water be used for oil fires?

Question

I know oil floats on water. But when you spray water on an oil fire, the water has to sink, meaning it goes 'through' the burning oil, which means it has to cool the oil below kindling point and/or temporarily choke off oxygen. So why doesn't water work?

Answer 1

Because the oil is so hot, that it scatters in reaction to water. So, in fact, the fire would spread!
It has nothing to do with cooling, although a very very small oil fire controlled, in a deep pan, with enough water it could put it out, its not impossible, however the hot oil will react by jumping regardless. The best way is to smother it by using powder, flour, or even covering the pot with a lid.

Answer 2

Your thinking is slightly flawed...

Water and oil do not intermingle or mix (under some circumstances, water and oil can emulsify). So, the oil that is fueling the fire will allow the water to break through it as it floats on top of it, and the water will collect under the film of oil. Since the water cannot break down the oil to diffuse the fire, it is an extremely poor extinguisher for oil-based fires. And, since the oil floats on top of the water, it has plenty of oxygen supply to help sustain a fire. Foam, or foaming agents, has been the most effective form of extinguishing oil-based fires, as the foam floats on top of the water (much like the oil), and chokes off the oxygen supply.

Answer 3

Ok so to pu tout oa fire, you need to cut its oxygen source or cool it down.

Anyways, ok when you burn wood, the wood is burning itself, or coal.

Oils, the liquid, doesn't burn. Its the vapor that catches on fire.

YOu can hypothetically put out ao fire with gasoline. Neat trick to show this. Set a splint of wood on fire and get some tiny container, like a testtube full of gasoline and throw the splint in. The top will ignite, but you'll see below in the testtube, splint's fire beign put out.

Anyways, the liquid oil is not ever on fire, its the vapour which is burning. Even throwing water on it, the air will still be hto enough and when the oil gets back to the top its vapours will ignite again. Not to mention the process will spread out the oil too.

Answer 4

In order for water to work on a fire, it must effectively cover it with a liquid layer, thus choking off the oxygen. The trouble is, an oil fire is much, much hotter than the boiling point of water. Therefore, if you put water on it, it will all evaporate- instantly, and explosively. Of course, if you put enough water on it, you would achieve the desired effect. Dropping an entire lake on your fat-fire for instance, would put it out pretty fast.

Answer 5

I don't know for sure, but I think it's because you need to put out the fire at its source, so unless you can cover the oil with water it wouldnt work.
With wood fire, you wet the wood so the fire can't burn on it anymore. You can't wet or cover oil with water, so the fire continues to burn. Putting water through the flames doesn't douse them.