You can bring it into the room, but do not take it into the heat. Most phones are rated to around 35°C in operation, and an infrared sauna runs well above that.
What the heat does to a phone
Lithium-ion batteries degrade faster at high temperatures, and the damage accumulates rather than reversing when the phone cools. Before that, the phone will protect itself: screens dim, charging stops, apps close and most phones eventually display a temperature warning and shut down until they cool.
Humidity is the second problem. Water-resistance ratings are tested with cool water, not hot vapour, and steam finds its way past seals that cope perfectly well with rain. In a traditional sauna that matters more than in an infrared cabin, which is drier — but sweat is still sweat.
Infrared Sauna is one of five treatments at Floatwell Cambridge, 500 m from the station — about infrared sauna →
What we suggest
- Leave it outside the cabin. The room is private, so it is not going anywhere.
- If you want music, play it from outside the cabin rather than taking the phone in with you.
- If you are waiting on a call you cannot miss, keep the phone in the room and the door ajar rather than bringing it into the heat.
- Do not charge a phone in a hot or humid room.
The other reason to leave it
Thirty minutes is not very long, and it is one of the few blocks of time in a week where there is genuinely nothing to do. Most people who bring a phone in spend the session scrolling and leave feeling much as they arrived. The treatment works better when you are not also working.
If the idea of half an hour with no phone is uncomfortable, that is worth noticing rather than solving.
Red light and floatation
The red light bed is less punishing on a phone — no steam and lower ambient heat — but you should keep your eyes closed throughout, so there is not much to look at. Floatation is the opposite: the room is humid, the water is saturated with salt, and a phone that goes in the tank does not come out working. Leave it in the room.
Valuables
Treatments take place in private rooms, so your belongings stay with you rather than in a shared changing area.