by Nick Gromicko, CMI®
A sauna is a small, sealed room, typically constructed of wood, designed to safely increase the user’s body temperature through a combination of heat and well-controlled humidity. Saunas are used recreationally and therapeutically, as users find them relaxing and health-promoting.
Facts and Figures
- “Sauna” is the only Finnish word in the English dictionary. Traditionally, the Finns used the sauna as a place to clear the mind, give birth, and prepare the dead for burial. They were not used for weight loss or as part of an exercise regimen, which are newer concepts for their use today.
- Saunas can be divided into two basic styles:
- infrared saunas directly warm occupants and other objects (much like the sun) using charcoal or other objects; and
- conventional saunas heat the room indirectly by warming the air.
- One of the earliest sauna designs is the smoke sauna, in which stones warm the room after being heated by a fire, which is extinguished before the room is ready for bathers. The smoke is vented from the sauna but its aroma lingers. The concept was nearly abandoned but has seen a revival over the past few decades.
- Saunas stimulate the cardiovascular system and should not be used by anyone with high blood pressure, diabetes, heart disease, or while under the use of antibiotics or other drugs. Never stay in a sauna longer than 30 minutes. While it may be fun to see who can stay in the sauna the longest, this sort of game is extremely dangerous and has led to injury and even death. One experienced sauna devotee died in a sauna competition in August 2010.
- Never wear jewelry in the sauna, as the metal and stones may heat up and burn exposed skin.
- Use a towel as a barrier between yourself and the seat in a public commercial sauna to protect yourself against disease. Strains of antibiotic-resistant bacteria, known collectively as methicillin-resistant Staphylococcus aureus, have been shown to inhabit excessively humid and poorly cleaned public saunas and steam rooms. Reducing the humidity can also control the risk of transmission.
- Children should not use saunas because they have trouble thermo-regulating to stave off hyperthermia.
Recommended Sauna Design Features
Adequate ventilation is perhaps the most overlooked sauna design feature. Outgoing ventilation expels stale air and reduces humidity-spawned mildew and moisture, which can cause wood decay. Incoming ventilation brings in fresh air, ensuring the safety and comfort of the users. Saunas typically have a vent behind the stove and another on the opposite wall near the ceiling. While the sauna may vent to the outside of the building, this is not required in residential saunas, and many systems utilize interior ventilation to heat the adjacent living space.
Some other essential design features include the following:
- Freestanding saunas must have a solid foundation.
- Sauna doors should be sealed and insulated.
- The sauna door should swing outward and should not be equipped with a latching mechanism. If the user is in distress, he should be able to easily push his way out of the sauna.
- Saunas should be constructed from a decay-resistant species of tree, such as cypress, redwood, spruce, cedar or Douglas fir.
- Any electrical wiring should be moisture-proof and able to resist high temperatures.
- Metal, especially screw heads, should not be exposed where people sit, lean or walk. Metal will get excessively hot and could burn exposed skin.
- The ceiling height should be between 6½ to 7½ feet, but not higher, as heat will uselessly pool above the user’s head. Also, undue stress will be placed on the heater, which will be forced to work harder to heat the room.
- The temperature should not exceed 195º F, as recommended by Underwriters Laboratories. Saunas heated by wood-burning stoves may be capable of exceeding this temperature, but this is not advisable, as it can endanger the users' safety. Saunas that utilize excessive amounts of steam should be set to a lower temperature, as wet heat can cause scalding.
- The floor can be made from concrete, vinyl or tile, but not carpet, which will deteriorate from the heat and humidity and create moisture-caused health hazards. Carpet is also a fire hazard.
- To best utilize the space and to achieve a balanced temperature throughout the sauna, the shape of the sauna room should be nearly square.
- The sauna should be regularly inspected for mildew and wood decay around its exterior.
In summary, saunas are sealed, heated rooms used for therapeutic purposes and relaxation, but must be used and maintained properly to ensure the health and safety of their users.