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by falcolas 1029 days ago
I'm not sure a bucket would be enough to cool a person down if they have no other form of heat dissipation available to them - specifically I'm not sure feet alone could dissipate heat fast enough. If the water is too cold (around 70°F IIRC), your body would constrict the blood vessels to your hands and feet, limiting how much heat could be moved to those extremities from your core.

Hence mentioning a bath tub.

Some interesting reading to go along with this topic:

https://ntrs.nasa.gov/api/citations/19750007244/downloads/19...

Of particular note is the need to remove about 1k BTU/hour when walking/doing light work, and that's only from metabolic heat generation.

And 1 BTU raises 1 pint of water 1 degree, so 1k BTU/hour would raise 5 gallons of water by an unrealistic 25° every hour.
1 comments
jncfhnb 1029 days ago
You’re going to need to set some practical constraints here.

Can you survive wet bulb temperatures given a bucket of water indefinitely? No. Can you survive working hard labor with the water bucket? No. Can you survive wet bulb events significantly higher than the threshold? No.

Can you survive several hours in a typical (current typical) wet bulb event? Yes, definitely. Bucket of water is fine.

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falcolas 1029 days ago
> Can you survive several hours in a typical wet bulb event?

I'm going to vote maybe. At best, it'll be close.

Resting metabolic output is about half the active value I provided (per NASA's PDF). That means for a bucket of water that starts at 32°, you have 5 hours before the bucket is also 95° if you discount ambient heating from the air, circulatory constriction, and assuming no prior conditions.

Since you can't discount those (and are unlikely to find barely-not-frozen water for an entire city's population), survival for more than an hour or two is nowhere near guaranteed.

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sokoloff 1028 days ago
> survival for more than an hour or two is nowhere near guaranteed.

Does that pass your personal sniff test for reasonability? Have you ever soaked in a 104°F (40°C) hot tub for an hour or more? Was your survival in serious doubt?

Wet bulb temperatures in excess of 35°C need to persist for around 6 hours to represent a serious hyperthermia risk. This is not a "you will die inside of 1-2 hours" scenario.

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