The aluminum foil shelter that Wildland Firefighters carry as part of their 50 lb back-country fire kit is intended to be that last resort when the fire is not only gaining on their position but has skipped ahead, and they are trapped with fire coming from all sides.


The physics of this 'last chance' technology are real and can be easily calculated. Hotshot Firefighters drill on this like their very lives depend on it. Any fire is the equation of heat + fuel + oxygen. Heat is temperature of the the available mass either mitigated by high humidity, or greatly boosted by low humidity. Fuel in a forest is a given. Oxygen in the outdoors is a matter of wind speed.

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