# Compressed air explosing or fire

## Main Question or Discussion Point

Please every1 put your 2 cents in. I joined this forum as a few of my buddys are arguing about compressed air. here is the situation.
We have a car with a air compressor (not an oxygen tank) in the trunk the car is rear ended and catches on fire, during the accident the tank was broken open. what would happen?
Would the compressed air explode?
would it add to the fire and make it larger?
or would nothing happen?

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DaveC426913
Gold Member
So you're asking if the air would create a fireball, not whether the tank would explode.

LURCH
Two possibilities; the tank is punctured but holds its structural integrity for the most part, in which case the air rushes out through the rupture. Otherwise, the rupture could comprimise the structural integrity of the tank, like perhaps causing a crack or rip in the metal that continues along its entire length. In that case, the air would escape in a small fraction of a second, accompanied by fragments of metal, which could easily fit most people's definition of an "explossion."

DaveC426913
Gold Member
Two possibilities; the tank is punctured but holds its structural integrity for the most part, in which case the air rushes out through the rupture. Otherwise, the rupture could comprimise the structural integrity of the tank, like perhaps causing a crack or rip in the metal that continues along its entire length. In that case, the air would escape in a small fraction of a second, accompanied by fragments of metal, which could easily fit most people's definition of an "explossion."
See, this is what I thought he was asking at first too. But I think he's actually asking how the compressed air would act in the presence of fire. Would the compressed air basically make a fireball, I think is what he wants to know.

yes sorry for the bad wording just not sure how else to put it. would the escaping air from the tank cause the fire to "fireball" or become larger? would that air feed the fire? or would it be to much air? A fire marshal told me that it would be a huge explosion because compressed air is oxygen and extremely flammable. I wasnt aware that compressed air is oxygen? i thought it 2 different things. I know compressed air contains oxygen but isnt air moslty nitrogen? thanks!

DaveC426913
Gold Member
yes sorry for the bad wording just not sure how else to put it. would the escaping air from the tank cause the fire to "fireball" or become larger? would that air feed the fire? or would it be to much air? A fire marshal told me that it would be a huge explosion because compressed air is oxygen and extremely flammable. I wasnt aware that compressed air is oxygen? i thought it 2 different things. I know compressed air contains oxygen but isnt air moslty nitrogen? thanks!
If you blow on a dying firepit, the embers will glow and eventually re-ignite.

Part of the thing that keeps a fire in check is the inavailablity of oxygen. Giving a fire an unlimitged supply of oxygen (even if you also give it an unlimited supply of nitrogen), will definitely increase it. I'm just not sure how much.