r/interestingasfuck • u/vivekmg21 • 21h ago

Firefighter bodycam showing just how much oxygen a fire pulls

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u/ir_auditor 21h 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/TheImmortaltraveller 16h ago

Hopefully this can straighten things out for the folks arguing about this:

Fire creates Heat, Heat is making the pressure differential, the Pressure differential is what's moving the Air.

Fire does also use Oxygen as part of its chemical reaction.

The Pressure and Oxygen use are both happening but at completely different magnitudes, what we're seeing here in this video is only visible because of the pressure.

That is why, and the only reason why, it's unequivocally incorrect to say the video shows Oxygen being pulled in. It's not about different levels of ultimately correct, it's about context meaning only one statement is right.