When I was really young, like 11 or 12, I attempted suicide by exposure. There was probably around 2 feet of snow outside, and it was a school day. I pretended that I was going to the bus stop as usual and my mother had no suspicions whatsoever. I instead snuck into our backyard , took off my outer layer of clothing, and immersed myself in the snow. I sat there for 2 hours or so crying and hoping for death to arrive. The cold was unbearable at first, but after a while I didnt feel anything. Eventually I got too scared and ran back into the house. I immediately started a hot bath to bring my temperature back to normal, and my god, that was one of the worst pains i've ever felt in my life . Especially my private parts and lower extremities, which had begun to lose their color. I ended up getting a call from my frantic mother asking me why I wasn't at school. I lied and said I missed the bus lol. She came home and I actually finished the rest of the school day after my whole ctb attempt.
In summation, I do not reccomend ctb via exposure. Unless you're passed out high or something.