[generic92034]

So you are saying a small amount of water would be enough to cool you down when it is (for example) 35° C at 90% humidity? How would that work? Evaporative cooling is out, for the most part and a small amount of water would be heated up to 35° C in no time.

[jncfhnb]

You just put your feet in the water and transfer heat to the water. It would not heat up to 35 in no time.

[sokoloff]

1 BTU is the amount of energy required to raise 1 pound of water by 1°F. Take 5 gallons (~42 pounds) at say 70°F (21°C). Raising that 42 pounds of water by 25°F/14°C will take just over 1K BTU.

That's maybe 2 hours of cooling per person and it's not at all obvious that during such a heat event that you'll have access to a continued source of 70°F/21°C water. If you only have access to 82°F/28°C water, 5 gallons only lasts you an hour or less.

[jncfhnb]

So let’s use your logic and ask how long could a person survive in a sauna?