I always use cool/warm water on my hair systems. I do everything I can to keep the hair from drying out. I would never go into a sauna with my hair system. There’s a guy I see at the gym who’s wearing one of the best hair systems I’ve ever seen. I only know he wears because I’ve seen him bald and one day he showed up with hair. It’s totally undetectable! His own hair is very short on the sides and his system is short on top and it has an amazing blend. Whoever works on his hair really knows what they’re doing. His density is light and you can see his scalp through it. He comes out of the shower with his hair soaking wet and I’m amazed how real it looks. He uses the steam room every day. Within a couple of weeks I started to notice his hair drying out and it also began to fade rapidly. His hair went from brown to copper. After about a month his system looked very obvious. It looked better the following week after he got it colored but it still looked dry. I would definitely stay away from steam rooms and saunas.