the air
That the supply of oxygen for the fire
A source of heat, a source of fuel, and oxygen.
Fire needs the oxygen in the air. Any other source of oxygen would also sustain fire.
To create a fire you need a fuel source of some kind, oxygen (O2), and a heat source.
Fuel, Oxygen and a heat source. Fuel, Oxygen and heat are everywhere why is the whole earth not on fire? because it is not Heat but a source of ignition that is needed.
There is what is known as a "fire/combustion" triangle, which has the three components necessary for fire: oxygen, fuel, heat
there isn't an actual chemical to start fire. all you need is an ignition source, oxygen, and a fuel source (such as wood)
Fuel, oxygen and an ignition source
heat,oxygen,fuel source
Fuel, oxygen, & an energy (heat) source.
Remove the oxygen supply, smother the flames thus removing the oxygen, remove the fuel source, or wet the fuel source.