International Sauna Association (ISA) defines a sauna bath as:

“The sauna bath is a health-promoting and relaxing hot-air bath in which overheating and cooling alternate. In a room made of wood, with a typical climate of about 80-105 degrees C, about 100 cm above the top bench, as well as a low level of humidity, which is briefly increased by infusions, the whole body is heated several times and then cooled with outside air and cold water.”