A participant in the World Sauna Championships in Finland died after suffering severe burns in temperatures of 110°C. So, what is a safe temperature in a sauna?
Sitting in a room with water so hot it could boil might seem crazy, but that’s exactly what competitors at the World Sauna Championships in Finland have been doing for more than a decade.
Five-time champion Timo Kaukonen handled the 110-degree Celsius (230-degree Fahrenheit) championship temperatures well, lasting more than 16 minutes in 2003.
However, this year the Finnish player fell along with his Russian opponent Vladimir Radizinsky in the sixth minute of the final. Mr. Radizinsky later died in hospital.
The organisers later claimed that such high temperatures are not uncommon in Finnish saunas.
Kristian Miettinen, CEO of the Finnish Sauna Association, said most sauna users maintain the temperature at around 80 degrees Celsius for five to six minutes.
However, being a self-confessed “sauna maniac”, he usually heats the room to 100 degrees Celsius, while others prefer short sessions of three to four minutes at a temperature of 130-140 degrees Celsius.
“People who like to swim in the hottest temperatures always wear felt hats and flip-flops, as wooden surfaces tend to get very hot.
“How long you stay there depends on your body type. Then you have to take a shower or jump into a lake or the sea.”
The association recommends that people with underlying health problems such as heart disease, high blood pressure, asthma or skin conditions maintain a “moderate” temperature of below 90 degrees Celsius, and pregnant women below 70 degrees Celsius.
However, Mr Miettinen said he could not understand why temperatures of “only 110 degrees Celsius” could kill people, while people could happily enjoy temperatures of 160 degrees Celsius.
He said informal competitions are common among young people in Finland, but participants know when to stop and calm down.
However, his organisation has spoken out against the world championships, which he says “have nothing to do with saunas”.
“It’s an extreme race – a test of endurance to heat stress,” he said, adding that competitors are exposed to high temperatures repeatedly throughout the day.
John Brewer, professor of sports science at the University of Bedfordshire, said if body temperature rises to dangerous levels it could be fatal.
He said that although the body temperature is between 37 and 38 degrees Celsius, an increase of just four degrees can lead to hyperthermia, collapse and coma.
“The main defence mechanism is sweating – the loss of latent heat to the environment through the evaporation of sweat, allowing the body to stay cool,” Professor Brewer said.
For example, during exercise, sweating helps regulate body temperature below dangerous levels of around 39 degrees Celsius.
Heat and humidity can also affect the efficiency of sweating because the temperature difference between the body and the outside environment is reduced, making it more difficult for sweat to evaporate.
However, this means that the heart needs to pump blood faster to supply the skin and muscles. If this continues for too long and the body continues to heat up, the brain can become deprived of oxygen and blood supply, leading to brain failure.
“You don’t normally sweat in that environment, but extreme heat can cause your body temperature to rise to that level,” he added.
Dr Keith Judkins, an injury prevention specialist at the British Burns Association, said he was not surprised that competitors had suffered burns.
“Serious tissue damage occurs within 10 seconds of contact with water at 60C (140F), so it must be this dry heat that makes it tolerable,” said Dr Judkins, from the burns unit at Pinderfields Hospital in Wakefield.
While playing, water is poured onto the stones in the oven every 30 seconds to increase the heat and also to raise the humidity.
Dr Judkins compared 110 degrees Celsius to a “cold oven” and said such “cooking temperatures” could cause burns due to the high humidity.
However, he added that even if competitors do not suffer immediate burns, their bodies will reach their endurance limits and there is a risk of overheating.
Copyright © 2025 BBC. The BBC is not responsible for the content of external websites. Find out more about our understanding of external links.