Three of four to make fire...

[Externet]

Read somewhere many years ago, that any three of :

Temperature, spark, fuel, oxygen

Are needed to make fire. Is that imprecise/incorrect ?

[Mordred]

Temperature or spark, fuel and oxygen are required. However as accurate as that is . There is one aspect missing. For this I will refer to haylon fire extinquishers . How did they work. They didn't cool the fuel, one version didn't displace oxygen and they didn't remove the fuel.

 

Instead it was realized haylon worked by interfering with the rapid oxydization or preventing the chemical chain reaction of oxygen with the fuel. So I would say there is 4 requirements.

 

Fuel, spark, oxygen and chemical chain reaction.

[MigL]

Yes, I deal with pyrophoric substances in my work and have limited fire-fighter training.

The training specifies all four are needed.

In effect, a spark is only needed for ignition and temperature is only needed to sustain.

Fuel and oxidizer are always needed ( unless combined in an organic oxidizer ).

[Mordred]

Here is a short coverage of Halon

http://www.h3rcleanagents.com/support_faq_2.htm

 

too bad it affects the ozone layer and is illegal in most countries as a result.

[mathematic]

Read somewhere many years ago, that any three of :

Temperature, spark, fuel, oxygen

Are needed to make fire. Is that imprecise/incorrect ?

Fuel and oxygen are always needed. Either spark or temperature is needed to get things going.

[Endy0816]

 

This is the one I learned.

 

You need to supply the activation energy for the reaction to take place. Other fires or "sparks" of typically burning wood or metal, can be a source, but you can accomplish the same thing with heat alone(autoignition). We probably all have fond memories of seeing flames once, while attempting to cook on a stove or in an oven.

Edited December 14, 2014 by Endy0816

[John Cuthber]

In some circumstances it's possible to have fire without oxygen.

Some things will burn in chlorine; most things will burn in fluorine.

[MigL]

Endy0816 has it right. Trainers used to talk of a fire triangle, but it has been amended to a tetrahedron.

Yes I have fond memories of fires also...

Flames 50 ft high around a gasholder containing several hundred kgs of phosphine gas.

With the 'real' firefighters afraid to come into the plant.

Sigh.

 

The last and only chemistry I actually recall from school ( gr 13, pre-university ) is that titanium burns in a nitrogen atmosphere.

[Endy0816]

Yeah, we are just bad about considering fire only in terms of our atmospheric composition. Admittedly it does play a large role in terms of what we see on a regular basis, but you can end up with cases where the reaction could care less about oxygen deprivation.