Saunas and steam rooms both use heat therapeutically, but they do it in different ways. Essentially, a sauna uses dry heat, while a steam room incorporates high humidity and warmth. Both open up the pores of the body, helping them to eliminate toxins through sweat, ease joint pain, improve circulation, relax bathers, and strengthen the immune system. Which one a person uses is a matter of personal preference; most people who cannot endure dry heat, for example, greatly enjoy a steam room, while people who do not enjoy the wet sensation benefit from using saunas instead.
A sauna uses a heater or a wood burning stove in an enclosed room to elevate the temperature, usually above 160°F (71°C). In a traditional dry sauna, bathers sit or lie in the room to absorb the warmth, which elevates the body's internal temperature, stimulates blood flow, and opens up the pores. After a set period of time, the bather jumps out into a cold plunge or shower, and then rests at room temperature before re-entering for another round.
Some saunas incorporate small amounts of steam, usually in the form of cold water that is sprinkled on the heater, or rocks placed on top of the stove. Often, the water is mixed with essential oils, such as lavender for relaxation or eucalyptus for easing muscle pain and killing germs. The brief burst of humidity caused by the steam makes the sauna feel more hot, and can in fact scald bathers if the room is too hot, causing the steam to boil the skin it contacts. For this reason, water is used sparingly.
A steam room is maintained at a much lower temperature, usually not more than 110°F (43°C), but the humidity is kept very high — usually around 100%. Bathers who enter are usually immediately surrounded by a cloud of vapor, and sit or lie on benches to absorb the benefits of the steam. The cooler temperature makes steam rooms more bearable for some people, and also helps asthmatics and other people suffering from breathing conditions.
Bathers using either type of therapy should immediately exit if they feel at all unwell, and they should also drink plenty of fluids. Drinking fluids helps the body to eliminate toxins through sweating and also prevents dehydration, which often causes dizziness and fainting. Individuals who are in a public sauna or steam room and notice someone feeling unwell should help him or her out and ask an attendant for assistance.