A hot room at a spa is often referred to as a SAUNA. A SAUNA is a small room or house designed as a place to experience dry or wet heat sessions, or an establishment with one or more of these facilities. The heat and humidity in a SAUNA can be quite intense, and the temperature can range from 70 to 100 degrees Celsius. The purpose of a SAUNA is to relax muscles, improve circulation, and promote sweating to cleanse the body.