Sounds hot. Here's the trick: they measure it right under the ceiling. It is like checking the bath water with your hair.
So why do saunas abroad feel cold? The dial, or the ladle? A Finnish heater maker's own manual: above the heater, 82. On the top bench, 60. On the floor, 38. So where did the heat go? Into the ceiling.
And then the other rule: no water on the rocks. At one American university gym, users poured it anyway. The heater shorted out. About five thousand dollars. But Finland's own manuals recommend 65 to 80 degrees. Finns run theirs hotter: the Finnish Sauna Society says 80 to 100. The cold foreign sauna was never about the dial. It's the missing ladle.
A Helsinki university gym has the fairest rule: ask others before throwing water. Ask first. Then throw.
Never tamper with a sauna heater. Feel unwell? Leave the heat.
Sources: International Residential Code 2021, M1902.4 (as adopted in Seattle): a thermostat that will "limit room temperature to not greater than 194°F (90°C)", its sensing element "within 6 inches (152 mm) of the ceiling" (a model code that states and cities adopt; commercial rules differ); Harvia's US heater manual (Harvia Club): "180 °F (82 °C) above Sauna heater … 140 °F (60 °C) on upper bench level … 100 °F (38 °C) at floor level", an illustration, not a measurement of any one gym, and "A suitable temperature for the sauna room is about 149-176 °F (65-80 °C)"; the Finnish Sauna Society "recommends heating a sauna to between 80 and 100 degrees Celsius" (Yle News, 17 Apr 2023), and "Most Finnish saunas are heated to 75-90 degrees Celsius" (L. Liikkanen, Saunologia); a US university student newspaper, 2017 (a gym's heater "shorted out due to water being poured on it by users", replacement about $5,000); UniSport Helsinki: "Ask others before throwing water on the heater and take different sauna preferences into account." The thermal-camera pictures in the film are drawings, not measurements.
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