A hot tub has a control panel with which the temperature is set to the desirable level. A good system has a panel that shows both the actual temperature and a setting temperature, which should be easy to read and set even in poor lighting.
Temperature control in hot tubs is important for both comfort and safety. The National Pool and Spa Institute recommends a maximum temperature of 104 degrees and a maximum soak time of 15 minutes, to avoid raising body heat to dangerous levels. Children, infants and pregnant women are more vulnerable to heat and should use lower temperatures. Water temperature should be checked with a floating thermometer before getting in. Users should avoid consuming alcohol and drugs while enjoying a hot tub, as these substances can increase the risk of hyperthermia.