Is it safe to use an iPhone during a sauna treatment?

Hello~ Adding on to with another resounding no… click on below and review.

Important handling information for iPhone - Apple Support*

*See the Apple Support article About splash, water, and dust resistance of iPhone 7 and later. To prevent liquid damage on iPhone, avoid the following:

• Swimming or bathing with iPhone
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• Exposing iPhone to pressurized water or high velocity water, such as when showering, water skiing, wake boarding, surfing, jet skiing, and so on
• 
  
• Using iPhone in a sauna or steam room
• 
  
• Intentionally submerging iPhone in water
• 
  
• Operating iPhone outside the suggested temperature ranges or in extremely humid conditions
• 
  
• Dropping iPhone or subjecting it to other impacts
• 
  
• Disassembling iPhone, including removing screws

~Katana-San~

No, it is not OK. The humidity in a sauna will exceed the permissible level, and the temperature might also.

Simple answer. No.