It is a primary part of daily life for Estonians of the Voro community in Estonia.
In Estonian, it is referred to as saun. Sauna originates in Finland.
The sauna is a building or room with an elevated platform for sitting or lying. The building is heated by a stove covered with stones, which produces hot steam-laden air. The smoke from the burning wood circulates the room. Visitors usually visit the sauna together and remain there until their body sweats.
Usually, on the eve of a New Year's Eve, Estonians would take a sauna before midnight to cleanse their body and spirits for the upcoming year, similar to the Finnish tradition.
The smoke sauna is almost identical to the Finnish sauna tradition in that saunas have traditionally played a central role in a person's life in Estonia. Traditional saunas were used not only for washing but to ceremoniously wash brides, give birth, and make the final resting place of the dying, as well. In ancient Estonia, saunas were thought to be inhabited by spirits.
There is a rich range of traditions associated with it, including the actual bathing customs, the skill of making bath whisks, the building and repair of saunas, as well as smoking meat in the sauna.
A sauna session can be a social event in which people unclothe and sit or recline at a temperature between 70 and 100 °C (158 and 212 °F). The temperature induces relaxation and promotes sweating. They use a bundle of fresh leaves with birch twigs called a vihta (or vasta) to slap on the skin and stimulate pores and cells further. People use whisks to scrub off dead skin, and they beat their bodies with the hot steam. The smoke sauna tradition is a family custom that is primarily practiced on Saturdays, but it is also practiced before major festivals or family events.
After sweating, whisking, and relaxing the body, people cool themselves outside and rinse their skin with water. The procedure is repeated. Saunas are usually prepared by an older family member, with the assistance of children who gradually acquire the necessary skills.
As of today, the smoke sauna is still in use in Estonia. Smoke saunas are considered to be cheap, easy to build, and durable (if precautions are taken to prevent fire when building the sauna). In addition, its durability is ensured by the disinfectant properties of smoke.
References
(https://ich.unesco.org/en/RL/smoke-sauna-tradition-in-vromaa-00951)
(https://en.wikipedia.org/wiki/Sauna#Finnish_and_Estonian_sauna) (https://wikimili.com/en/Finnish_sauna)