When I was a kid and my parents built a sauna to our summer cottage, I spent two hours straight in the sauna, but that is pretty hardcore even on my standards. As long as you as you keep yourself hydrated, there is no real time limit how long you can be in a sauna. A normal sauna session usually consists of several short 5-20 minute sessions (depending on the amount of löyly thrown and the temperature of the sauna) where you go cool off in between.
You shouldn't stay in the sauna for more than 60 minutes.
The maximum temperature of an infrared sauna really does depend on which model a person owns. For example, the FAR infrared sauna typically gets as high as 110 degrees Fahrenheit. And for other versions, the sauna is best set from 120 to 130 degrees with a maximum of 140 degrees.
It is safe to use sauna every day, as long as you don't do it for long periods at a time.
Stay inside the sauna for no more than 30 minutes at a time and then lie down 10 minutes after use. If you use the sauna once a day, the evening is probably the best time. If you are ill, however, the morning may prove a better time because your energy levels are higher. Make sure you drink plenty of mineralized water before and after the sauna. Add minerals or juice to your water if it is mineral-free. It is also a good idea to add extra sea salt to your diet to replace minerals lost through sweating in the sauna. Use the sauna under supervision if you have a chronic condition. If you are debilitated or very sensitive to heat, begin with a shorter period of time in the sauna. The presence of an attendant or friend in the sauna can also be very helpful.
REALLY long time ago in Finland
Sauna suits are not meant to be worn in sauna. You are supposed to be naked in there.
Sauna twin is a product that makes you sweat, but disgraces the name of sauna because it has nothing to do with actual sauna.
In a Finnish sauna, yes. In a Turkish sauna, no.
In a Swedish sauna yes, in a Finnish sauna no.
Sauna World Championships are held in Finland, not Sweden. Swedish sauna is about 60 degrees colder than the Finnish sauna.
Sauna
You don't use sauna suit in the sauna.