A sauna (// or //; Finnish pronunciation: [ˈsɑunɑ]), or sudatory, is a small room or building designed as a place to experience dry or wet heat sessions, or an establishment with one or more of these facilities. The steam and high heat make the bathers perspire. Infrared therapy is often referred to as a type of sauna, but according to the Finnish sauna organizations, infrared is not a sauna.
- 1 History
- 2 Modern saunas
- 3 Use
- 4 Technologies
- 5 Other sweat bathing facilities
- 6 Around the world
- 6.1 Africa
- 6.2 Asia
- 6.3 Australia and Canada
- 6.4 Europe
- 6.5 North America and Central America
- 7 Traditions and old beliefs
- 8 Environmental effects
- 9 See also
- 10 References
- 11 Further reading
- 12 External links
The oldest known saunas in Finland were made from pits dug in a slope in the ground and primarily used as dwellings in winter. The sauna featured a fireplace where stones were heated to a high temperature. Water was thrown on the hot stones to produce steam and to give a sensation of increased heat. This would raise the apparent temperature so high that people could take off their clothes. The first Finnish saunas are what nowadays are called savusaunas, or smoke saunas. These differed from present-day saunas in that they were heated by heating a pile of rocks called kiuas by burning large amounts of wood about 6 to 8 hours, and then letting the smoke out before enjoying the löyly, or sauna heat. A properly heated "savusauna" gives heat up to 12 hours.
As a result of the Industrial Revolution, the sauna evolved to use a metal woodstove, or kiuas [ˈkiu.ɑs], with a chimney. Air temperatures averaged around 75–100 °C (167–212 °F) but sometimes exceeded 110 °C (230 °F) in a traditional Finnish sauna. When the Finns migrated to other areas of the globe they brought their sauna designs and traditions with them. This led to further evolution of the sauna, including the electric sauna stove, which was introduced in 1938 by Metos Ltd in Vaasa. Although the culture of sauna nowadays is more or less related to Finnish culture, the evolution of sauna happened around the same time both in Finland and the Baltic countries sharing the same meaning and importance of sauna in daily life, shared still to this day. The Sauna became very popular especially in Scandinavia and the German speaking regions of Europe after the Second World War. German soldiers had got to know the Finnish saunas during their fight against the Soviet Union on the Soviet-Finnish front of WWII, where they fought on the same side. Finnish hygiene depended so exclusively on saunas, that they had built saunas not only in mobile tents but even in bunkers. After the war, the German soldiers brought the habit back to Germany and Austria, where it became popular in the second half of the 20th century. The German sauna culture also became popular in neighbouring countries such as Switzerland, Belgium, the Netherlands and Luxembourg.
Archaeological sites in Greenland and Newfoundland have uncovered structures very similar to traditional Scandinavian farm saunas, some with bathing platforms and "enormous quantities of badly scorched stones".
Areas of the Nordic diaspora, such as the rocky shores of the Orkney islands of Scotland, have many stone structures for normal habitation, some of which incorporate areas for fire and bathing. It is possible some of these structures also incorporated the use of steam, in a way similar to the sauna, but this is a matter of speculation. The sites are from the Neolithic age, dating to approximately 4000 B.C.E.
The traditional Korean sauna, called the hanjeungmak, is a domed structure constructed of stone that was first mentioned in the Sejong Sillok of the Annals of the Joseon Dynasty in the 15th century. Supported by Sejong the Great, the hanjeungmak was touted for its health benefits and used to treat illnesses. In the early 15th century, Buddhist monks maintained hanjeungmak clinics, called hanjeungso, to treat sick poor people; these clinics maintained separate facilities for men and women due to high demand. Korean sauna culture and kiln saunas are still popular today, and Korean saunas are ubiquitous.
Originally borrowed from the early Proto-Germanic *stakna- whose descendants include English stack, the word sauna is an ancient Finnish word referring to the traditional Finnish bath and to the bathhouse itself. In Finnic languages other than Finnish and Estonian, sauna and cognates do not necessarily mean a building or space built for bathing. It can also mean a small cabin or cottage, such as a cabin for a fisherman.
Under many circumstances, temperatures approaching and exceeding 100 °C (212 °F) would be completely intolerable and possibly fatal if exposed to long periods of time. Saunas overcome this problem by controlling the humidity. The hottest Finnish saunas have relatively low humidity levels in which steam is generated by pouring water on the hot stones. This allows air temperatures that could boil water to be tolerated and even enjoyed for longer periods of time. Steam baths, such as the Turkish bath, where the humidity approaches 100%, will be set to a much lower temperature of around 40 °C (104 °F) to compensate. The "wet heat" would cause scalding if the temperature were set much higher.
In a typical Finnish sauna, the temperature of the air, the room and the benches is above the dew point even when water is thrown on the hot stones and vaporized. Thus, they remain dry. In contrast, the sauna bathers are at about 38 °C (100 °F), which is below the dew point, so that water is condensed on the bathers' skin. This process releases heat and makes the steam feel hot.
Finer control over the temperature experienced can be achieved by choosing a higher level bench for those wishing a hotter experience or a lower level bench for a more moderate temperature. A good sauna has a relatively small temperature gradient between the various seating levels. Doors need to be kept closed and used quickly to maintain the temperature inside.
Some North American, Western European, Japanese, Russian, and South African public sport centres and gyms include sauna facilities. They may also be present at public and private swimming pools. As an additional facility, a sauna may have one or more jacuzzis. In some spa centers, there are the so-called special "snow rooms," also known as a cold sauna or cryotherapy. Operating at a temperature of −110 °C (−166 °F), the user is in the sauna for a period of only about 3 minutes.
A steam sauna can take 30 minutes to heat up when first started. Some users prefer taking a warm shower beforehand to speed up perspiration in the sauna. When in the sauna users often sit on a towel for hygiene and put a towel over the head if the face feels too hot but the body feels comfortable. In Russia, a felt "banya hat" may be worn to shield the head from the heat; this allows the wearer to increase the heat on the rest of the body. Most adjustment of temperature in a sauna comes from,
- amount of water thrown on the heater, this increases humidity, so that sauna bathers perspire more copiously.
- length of stay in the sauna
- positioning when in the sauna
Heating caused by direct radiation will be greatest closest to the stove. Heating from the air will be lower on the lower benches as the hot air rises. Provided the sauna is not crowded, lying on a bench is considered preferable as it gives more even temperature over the body. Heating caused by fresh steam can be very different in different parts of the sauna. As the steam rises directly upwards it will spread across the roof and travel out towards the corners, where it will then be forced downwards. Consequently, the heat of fresh steam may sometimes be felt most strongly in the furthest corners of the sauna. Users increase duration and the heat gradually over time as they adapt to sauna. When pouring water onto the heater, it will cool down the heater, but carry more heat into the air via advection, making the sauna warmer.
Perspiration is a sign of autonomic responses trying to cool the body. Users are advised to leave the sauna if the heat becomes unbearable, or if they feel faint or ill. Some saunas have a thermostat to adjust temperature, but management and other users expect to be consulted before changes are made. The sauna heater and rocks are very hot—one must stay well clear to avoid injury, particularly when water is poured on the sauna rocks, which creates an immediate blast of steam. Combustibles on or near the heater have been known to result in fire. Contact lenses dry out in the heat. Jewellery or anything metallic, including glasses, will get hot in the sauna and can cause discomfort or burning.
Temperature on different parts of the body can be adjusted by shielding from the steam radiator with a towel. Shielding the face with a towel has been found to reduce the perception of heat. It may be advisable to put an additional towel or special cap on the hair to avoid dryness. Few people can sit directly in front of the heater without feeling too hot from radiant heat, but their overall body temperature may be insufficient. As the person’s body is often the coolest object in a sauna room, steam will condense into water on the skin; this can be confused with perspiration.
Cooling down is a part of the sauna cycle and is as important as the heating. Among users it is considered good practice to take a few moments after exiting a sauna before entering a cold plunge, and to enter a plunge pool by stepping into it gradually, rather than immediately immersing fully. In summer, a session is often started with a cold shower. Therapeutic sauna has been shown to aid adaptation, reduce stress hormones, lower blood pressure and improve cardiovascular conditions.
Increased frequency of sauna bathing is associated with a reduced risk of sudden cardiac death, cardiovascular disease, and all-cause mortality. Its usage is also associated with lower markers of inflammation in the blood and a reduced risk of high blood pressure. In addition, it is associated with a decreased risk of pneumonia and may temporarily relieve symptoms of the common cold. It is also associated with a reduced risk of dementia and Alzheimer's disease. It has been pointed out that many of the positive health effects reported with sauna usage, in particular its cardiovascular benefits, are associative and may be non-causal.
Saunas may not be safe in cases of unstable angina pectoris, recent heart attack, or severe aortic stenosis. Additionally, there is risk of heat prostration, hyperthermia, heat stroke and even death. Children and older persons who have heart disease or seizure disorders or those who use alcohol or cocaine are especially vulnerable. Sauna use can affect spermatogenesis, and has been associated with loss of fertility in men lasting up to two months. Prolonged stay in a sauna may lead to the loss of electrolytes from the body, as after vigorous exercise. The risk of dehydration leading to heat stroke may be reduced by regular sipping of water or isotonic drinks, but not alcohol, during the sauna. Sauna bathing with heavy drinking of alcoholic beverages or during alcohol withdrawal phase can have serious adverse health effects. With sauna associated deaths in Finland, individuals usually had an underlying chronic illness. More than 50% were men over the age of 50, and 30% were over 70. Most were also intoxicated.
In some countries the closest and most convenient access to a sauna is at a gymnasium. Some pool, major sport, and resort complexes also contain a sauna. Therapeutic sauna sessions are often carried out in conjunction with physiotherapy or hydrotherapy, gentle exercises that do not exacerbate symptoms.
Today there are a wide variety of sauna options. Heat sources include wood, electricity, gas and other more unconventional methods such as solar power. There are wet saunas, dry saunas, smoke saunas, and steam saunas. There are two main types of stoves: continuous heating and heat storage-type. Continuously heating stoves have a small heat capacity and can be heated up on a fast on-demand basis, whereas a heat storage stove has a large heat (stone) capacity and can take much longer to heat.
Smoke sauna (Finnish savusauna, Estonian suitsusaun, Võro savvusann) is one of the earliest forms of the sauna. It is simply a room containing a pile of rocks, but without a chimney. A fire is lit directly under the rocks and after a while the fire is extinguished. The heat retained in the rocks, and the earlier fire, becomes the main source for heating the sauna. Following this process, the ashes and embers are removed from the hearth, the benches and floor are cleaned, and the room is allowed to air out and freshen for a period of time. The smoke deposits a layer of soot on every surface, so if the benches and back-rests can be removed while the fire is alight the amount of cleaning necessary is reduced. Depending on size of the stove and the airing time, the temperature may be low, about 60 °C (140 °F), while the humidity is relatively high. The tradition almost died out, but was revived by enthusiasts in the 1980s. These are still used in present-day Finland by some enthusiasts, but usually only on special occasions such as Christmas, New Year's, Easter, and juhannus (Midsummer).
The smoke-sauna stove is also used with a sealed stone compartment and chimney (a heat storage-stove) which eliminates the smoke odour and eye irritation of the smoke sauna. A heat storage stove does not give up much heat in the sauna before bathing since the stone compartment has an insulated lid. When the sauna bath is started and the löyly shutter opened a soft warmth flow into the otherwise relatively cold (60 °C; 140 °F) sauna. This heat is soft and clean because, thanks to combustion, the stove stones glow red, even white-hot, and are freed of dust at the same time. When bathing the heat-storage sauna will become as hot as a continuous fire type-sauna (80–110 °C; 176–230 °F) but more humid. The stones are usually durable heat proof and heat-retaining peridotite. The upper part of the stove is often insulated with rock wool and firebricks. Heat-storing stoves are also found with electric heating, with similar service but no need to maintain a fire.
Continuous fire sauna
A continuous fire stove, instead of stored heat, is a relatively recent invention. There is a firebox and a smokestack, and stones are placed in a compartment directly above the firebox. It takes shorter time to heat than the heat storage-sauna, about one hour. A fire-heated sauna requires manual labor in the form of maintaining the fire during bathing; the fire can also be seen as a hazard.
Fire-heated saunas are common in cottages, where the extra work of maintaining the fire is not a problem.
Electric stove sauna
The most common modern sauna types are those with electric stoves. The stones are heated up and kept on temperature using electric heating elements. There is thermostat and a timer (eight hour maximum continuous heating time) on the stove. This type of heating is generally used only in urban saunas.
Other sweat bathing facilities
Many cultures have sweat baths, though some have more spiritual uses while others are purely secular. In Ancient Rome there was the thermae or balneae (from Greek βαλανεῖον balaneîon), traits of which survive in the Turkish or Arab hammam. In the Americas there is the Nahuatl (Aztec) temāzcalli [temaːsˈkalːi], Maya zumpul-ché, and the Mixtec Ñihi; in Canada and the United States, a number of First Nations and Native American cultures have various kinds of spiritual sweat lodges (Lakota: inipi, Anishinaabemowin madoodiswan). In Europe we find the Estonian saun (almost identical to the Finnish sauna), Russian banya, Latvian pirts, the European Jews' shvitz, and the Swedish bastu. In Asia the Japanese Mushi-Buro and the Korean jjimjilbang. The Karo people of Indonesia have the oukup. In some parts of Africa there is the sifutu.
Around the world
Although cultures in all corners of the world have imported and adapted the sauna, many of the traditional customs have not survived the journey. Today, public perception of saunas, sauna "etiquette" and sauna customs vary hugely from country to country. In many countries sauna going is a recent fashion and attitudes towards saunas are changing, while in others traditions have survived over generations.
In Africa, the majority of sauna facilities are found in more upmarket hotel, spa and health club environments and predominantly share both sauna heater technology and design concepts as applied in Europe. Even though outdoor temperatures remain warmer and more humid, this does not affect the general application or intended sauna experience offered within these commercial environments offering a traditional sauna and or steam shower experience.
In Iran, most gyms, hotels and almost all public swimming pools have indoor saunas. It is very common for swimming pools to have two saunas which are known in Persian as سونای خشک "dry sauna" and سونای بخار "steam sauna", with the dry type customarily boasting a higher temperature. A cold water pool (and/or more recently a cold jacuzzi) is almost always accompanied and towels are usually provided. Adding therapeutic or relaxing essential oils to the rocks is common. In Iran, unlike Finland, sitting in sauna is mostly seen as part of the spa/club culture, rather than a bathing ritual. It is most usually perceived as a means for relaxation or detoxification (through perspiration). Having a sauna room on a private property is considered a luxury rather than a necessity. Public saunas are segregated and nudity is prohibited.
In Japan, many saunas exist at sports centers and public bathhouses (sentō). The saunas are almost always gender separated, often required by law, and nudity is a required part of proper sauna etiquette. While right after World War II, public bathhouses were commonplace in Japan, the number of customers have dwindled as more people were able to afford houses and apartments equipped with their own private baths as the nation became wealthier. As a result, many sentōs have added more features such as saunas in order to survive.
In Korea, saunas are essentially public bathhouses. Various names are used to describe them, such as the smaller mogyoktang, outdoor oncheon, and the elaborate jjimjilbang. The word "sauna" is used a lot for its 'English appeal', however it does not strictly refer to the original Fennoscandian steam rooms that have become popular throughout the world. The konglish word sauna (사우나) usually refers to bathhouses with jacuzzis, hot tubs, showers, steam rooms, and related facilities.
In Laos, herbal steam sauna or hom yaa in Lao language, is very popular especially with women, and is available in every village. Many women apply yogurt or a paste blend based on tamarind on their skin as beauty treatment. The sauna is always heated by wood fire and herbs are added either directly to the boiling water or steam jet in the room. The sitting lounge is mix gender but the steam rooms are gender separated. bael fruit tea known in lao as muktam tea is usually served.
Australia and Canada
In Australia and Canada, saunas are found mainly in hotels, swimming pools, and health clubs and if used by both men and women, nudity is forbidden. In gyms or health clubs with separate male and female change rooms, nudity is permitted, however members are usually asked to shower before using the sauna and to sit on a towel.
Public saunas can be found throughout the Netherlands and Flanders, both in major cities and in smaller municipalities, mixed-gender nudity is the generally accepted rule. Some saunas might offer women-only (or "bathing suit only") times for people who are less comfortable with mixed-gender nudity; Algemeen Dagblad reported in 2008 that women-only, bathing suit-required times are drawing Muslim women to the sauna.
Finnish and Estonian sauna
A sauna session can be a social affair in which the participants disrobe and sit or recline in temperatures typically between 70 and 100 °C (158 and 212 °F). This induces relaxation and promotes sweating. The Finns use a bundle of birch twigs with fresh leaves (Finnish: vihta or vasta), to gently slap the skin and create further stimulation of the pores and cells.
The sauna is an important part of daily life, and families bathe together in the home sauna. There are at least 2 million saunas according to official registers. The Finnish Sauna Society believes the number can actually be as high as 3.2 million saunas (population 5.5 million).. Many Finns take at least one a week, and much more when they visit their summer cottage in the countryside. Here the pattern of life tends to revolve around the sauna, and a nearby lake used for cooling off.
Sauna traditions in Estonia are almost identical to Finland as saunas have traditionally held a central role in the life of an individual. Ancient Estonians believed saunas were inhabited by spirits. In folk tradition sauna was not only the place where one washed, but also used as the place where brides were ceremoniously washed, where women gave birth and the place the dying made their final bed. The folk tradition related to the Estonian sauna is mostly identical to that surrounding the Finnish sauna. On New Year's Eve a sauna would be held before midnight to cleanse the body and spirit for the upcoming year.
France, the United Kingdom and Mediterranean Europe
In France, the United Kingdom and much of Southern Europe, single-gender saunas are the most common type. Nudity is expected in the segregated saunas but usually forbidden in the mixed saunas. This is a source of confusion when residents of these nations visit the Netherlands, Belgium, Germany and Austria or vice versa. Sauna sessions tend to be shorter and cold showers are shunned by most. In the United Kingdom, where public saunas are becoming increasingly fashionable, the practice of alternating between the sauna and the jacuzzi in short seatings (considered a faux pas in Northern Europe) has emerged. Foreign visitors should also be aware that some small establishments advertised as 'saunas' are in fact brothels and it is rare to have a legitimate sauna with no other health spa or gym facilities in the UK.
In Portugal, the steam baths were commonly used by the Castrejos people, prior to the arrival of the Romans in the western part of the Iberian Peninsula. The historian Strabo spoke of Lusitans traditions that consisted of having steam bath sessions followed by cold water baths. Pedra Formosa is the original name given to the central piece of the steam bath in pre-Roman times.
In Germany, Austria, Luxembourg and South Tyrol (but rarely in the remainder of Italy), most public swimming pool complexes have sauna areas; in these locales, nudity is the generally accepted rule, and benches are expected to be covered by patrons' towels. These rules are strictly enforced in some public saunas. Separate single-sex saunas for both genders are rare, most places offer women-only and mixed-gender saunas, or organise women-only days for the sauna once a week. Loud conversation is not usual as the sauna is seen as a place of healing rather than socialising. Contrary to Russia and Nordic countries, pouring water on hot stones to increase humidity (Aufguss, lit: "Onpouring") is not normally done by the sauna visitors themselves; larger sauna areas have a person in charge (the Saunameister) for that, either an employee of the sauna complex or a volunteer. Aufguss sessions can take up to 10 minutes, and take place according to a schedule. During an Aufguss session the Saunameister uses a large towel to circulate the hot air through the sauna, intensifying sweating and the perception of heat. Once the Aufguss session has started it is not considered good manners to enter the sauna, as opening the door would cause loss of heat (Sauna guests are expected to enter the sauna just in time before the Aufguss. Leaving the session is allowed, but grudgingly tolerated). Aufguss sessions are usually announced by a schedule on the sauna door. An Aufguss session in progress might be indicated by a light or sign hung above the sauna entrance. Cold showers or baths shortly after a sauna, as well as exposure to fresh air in a special balcony, garden or open-air room (Frischluftraum) are considered a must.
In German-speaking Switzerland, customs are generally the same as in Germany and Austria, although you tend to see more families (parents with their children) and young people. Also in respect to socialising in the sauna the Swiss tend more to be like the Finns, Scandinavians or Russians. Also in German-speaking countries, there are many facilities for washing after using the sauna, with 'dunking pools' (pools of very cold water in which a person dips themselves after using the sauna) or showers. In some saunas and steam rooms, scented salts are given out which can be rubbed into the skin for extra aroma and cleaning effects.
Hungarians see the sauna as part of a wider spa culture. Mixed genders use the sauna together and wear swimsuits. Single-sex saunas are rare, as well as those which tolerate nudity. Some Hungarian saunas have so-called "snow rooms" that look like little cages with snow and icicles, where visitors can cool down for a couple of minutes after each sauna session.
Czech republic and Slovakia
In Czech Republic and Slovakia saunas have long tradition and are often found as part of recreational facilities, as well as public swimming pools. Many people are regular goers, while many never go. Saunas became more popular after about the year 2000, when large aquaparks and wellness centers included them. Nudity is increasingly tolerated, many places prohibit the use of swimsuits, however most people cover themselves with a towel. Showers are typically semi-private. Having men and women only days was the norm in the past, but today, men-only facilities are rare, while women-only hours are sometimes provided.
Norway and Sweden
In Norway and Sweden saunas are found in many places, and are known as 'badstu' or 'bastu' (from 'badstuga' "bath cabin, bath house"). In Sweden, saunas are common in almost every public swimming pool and gym. The public saunas are generally single-sex and may or may not permit use of swimwear. Rules for swimwear and towels for sitting on or covering yourself differ between saunas. Removing body hair in the sauna, staring at other's nudity or spreading odors is considered impolite.
Russia, the Baltics and Eastern Europe
In Estonia, Latvia, Lithuania and Russia sauna-going plays a central social role. These countries also have the tradition of massaging fellow sauna-goers with leafy, wet birch bunches: vasta or vihta in Finnish, viht in Estonian, slota in Latvian, vanta in Lithuanian, venik (веник) in Russian. In Latvian, sauna is pirts, in Lithuanian, it is pirtis.
In Russophone nations the word banya (Russian: Баня) is widely used also when referring to a public bath. In Russia, public saunas are strictly single-sex, while in Finland, Estonia, Lithuania and Latvia, both types occur. During wintertime, Finns often run outdoors for either ice swimming or, in the absence of lake, just to roll around in the snow naked and then go back inside. This is popular in Estonia, Latvia, Lithuania and Russia as well. Finnish sauna is traditionally the same as Russian banya despite the popular misconception that Finnish sauna is very dry.
In ex-USSR there are three different types of saunas. The first one, previously very popular especially during the Soviet Era, is the public sauna or the banya, (also known as the Russian banya), as it is referred to among the locals, is similar in context to public bath houses in Russia and in all ex-Soviet nations. The banya is a large setting with many different rooms. There is at least one sauna (Finnish style), one cold pool of water, a relaxation area, another sauna where fellow-sauna goers beat other fellow-sauna goers with the leafy birch, a shower area, a small cafeteria with a TV and drinks, and a large common area that leads to the other areas. In this large area, there are marble bed-like structures where people lie down and receive a massage either by another sauna-member or by a designated masseur. In the resting area, there are also other bed-like structures made of marble or stone attached to the ground where people lie down to rest between different rounds of sauna or at the very end of their banya session. There is also a large public locker area where one keeps one's clothes as well as two other more private locker areas with individual doors that can lock these two separate locker rooms.
The second type of sauna is the Finnish sauna type one can find in any gym throughout the world or a hotel. It could be in the locker room or mixed (i. e. male and female together). Attitudes towards nudity are very liberal and people are less self-conscious about their nude bodies.
The third type of sauna is one that is rented by a group of friends. It is similar to the public banya bath house type, except that it is usually more modern and luxurious, and is often rented by groups of friends by the hour for the use of partying and socializing. Here it can be single-sex or mixed-sex.
North America and Central America
In the United States, the earliest saunas that arrived with the colonists were Swedish bastus in the colony New Sweden around the Delaware River. The Swedish Governor at the time had a bathhouse on Tinicum Island. Today sauna culture enjoys its greatest popularity in the Lake Superior Region, specifically the Upper Peninsula of Michigan, especially the Keweenaw Peninsula, and parts of Minnesota, Wisconsin, and Iowa, which are home to large populations of Swedish and particularly Finnish Americans. Duluth, Minnesota, at its peak, had as many as 14 public saunas. Indeed, among Finnish farms in Great Lakes "sauna country", the cultural geographer Matti Kaups, found that 90% had sauna structures-more even than the farms in Finland. Elsewhere, sauna facilities are normally provided at health clubs and at hotels, but there is no tradition or ritual to their use. To avoid liability, many saunas operate at only moderate temperatures and do not allow pouring water on the rocks. A wider range of sauna etiquette is usually acceptable in the United States compared to other countries, with the exception that most mixed-sex saunas usually require some clothing such as a bathing suit to be worn. These are uncommon, however, as most saunas are either small private rooms or in the changing rooms of health clubs or gyms. There are few restrictions and their use is casual; bathers may enter and exit the sauna as they please, be it nude, with a towel, dripping wet in swimsuits or even in workout clothes (the latter being very unusual). Like many aspects of US culture, there are few prescribed conventions and the bather should remain astute to "read" the specific family or community's expectations. Besides the Finnish Americans, the older generation of Korean-Americans still uses the saunas as it is available to them. Sauna societies are beginning to emerge in colleges across America, with the first one being formed at Gustavus Adolphus College.
A cultural legacy of Eastern European Jews in America is the culture of 'shvitz', which used to be widespread in the East Coast and occasionally in the Pacific West Coast. 
The Sweat lodge, used by a number of Native American and First Nations traditional ceremonial cultures, is a location for a spiritual ceremony. The focus is on the ceremony, and the sweating is only secondary. Unlike sauna traditions, and most forcefully in the case of the Inipi, the sweat lodge ceremonies have been robustly defended as an exclusively Native expression of spirituality rather than a recreational activity.
Traditions and old beliefs
A Finnish word löyly [ˈløyly] is strictly connected to the sauna. It can be translated as "sauna steam" and refers to the steam vapour created by splashing water on the heated rocks. In many languages related to Finnish, there is a word corresponding to löyly. The same approximate meaning is used across the Finnic languages such as in Estonian leil. Originally this word meant "spirit" or "life", as in e. g. Hungarian lélek and Khanty lil, which both mean "soul", referring to the sauna's old, spiritual essence. The same dual meaning of both "spirit" and "(sauna) steam" is also preserved in the Latvian word gars. There is an old Finnish saying, "saunassa ollaan kuin kirkossa," – one should behave in the sauna as in church.
Saunatonttu, literally translated as "sauna elf", is a little gnome or tutelary spirit that was believed to live in the sauna. He was always treated with respect, otherwise he might cause much trouble for people. It was customary to warm up the sauna just for the tonttu every now and then, or to leave some food outside for him. It is said that he warned the people if a fire was threatening the sauna, or punished people who behaved improperly in it – for example slept, or played games, argued, were generally noisy or behaved otherwise immorally there. Such creatures are believed to exist in different cultures. The Russian banya has an entirely corresponding character called a bannik.
In Thailand, women spend hours in a makeshift sauna tent during a month following childbirth. The steam is typically infused with several herbs. It is believed that the sauna helps the new mother's body return to its normal condition more quickly.
Communal sweat lodges were commonplace in Ireland until the 19th century. The structure was a low stone mound with a small entrance. After the lodge was heated, participants entered and the door was sealed shut from the outside with a stone slab, typically for five hours before the participants were let out.
Saunas consume large amounts of electricity, contributing significantly to global climate change. A typical house in Finland with a sauna consumes 5,514 kWh/yr, more than 1,000kWh/yr more than the 4,158kWh/yr consumed by households without saunas, or about 1/4 of household electricity usage. Using the above estimate of 2 million to 3.2 million saunas installed in Finland, the energy consumption can be measured in gigawatts for that country alone. When multiplied by the number of units installed worldwide, the energy used globally releases a substantial amount of carbon into the atmosphere. Most of this energy is used by people in wealthy northern countries, as the installation of saunas in Africa, India, and elsewhere in the tropics is negligible. Collective saunas, such as those in village centers, gyms, or hotels, are generally used by many more people per unit of energy consumed than are private saunas, and therefore produce a lower per-user carbon footprint. Saunas that use electricity instead of wood offset their carbon burning to power plants far from the point of consumption, making the emissions involved in power production invisible to the average user.
- Body treatment
- Contrast shower
- Finnish sauna
- Hot spring
- Hot tub
- Mud bath
- Public bathing
- Public sauna in North West Europe
- Purification Rundown
- Steam room
- Steam shower
- Sweat therapy
- Taiwanese hot springs
- Turkish bath
- World Sauna Championships
- "Sauna". The American Heritage Dictionary of the English Language. Houghton Mifflin. 2001. Archived from the original on 26 February 2014.
- Dictionary Reference: sauna
- The Free Dictionary: sauna
- "Don't Call it Sauna – Sauna Digest". Sauna Digest. 12 July 2017. Retrieved 28 April 2018.
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