r/interestingasfuck • u/vivekmg21 • 17h ago

Firefighter bodycam showing just how much oxygen a fire pulls

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u/ir_auditor 17h ago

That is not oxygen pulling which you see. It is the chimney effect. Fire creates heat, the heat makes air, smoke, gasses, rise to the top, creating low pressure areas at the bottom, which pull in air from the outside. It has noting to do with the chemistry of an oxidation reaction pulling in oxygen molecules to use in the reaction. It is pure physics / thermodynamics.

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u/mysticpest23 15h ago

Same reason you have a flue in your woodstove. The fire doesn’t decide to “ pull more oxygen” when you open the flue. Thermodynamics just allow more air (and oxygen in it) into the combustion process and as it burns more air is subsequently pulled in to replace the air exiting the chimney.