Debate: Should we use hot water or cold water for saturation dives?

I was working out of Port Fourchon last month on a 300-foot bell dive, and the debate came up again about whether hot water suits are safer for decompression or if the old cold-water method has its place. A guy from Murphy Oil swore by cold water to reduce heat stress issues, but my supervisor said the hot water system prevents DCS better. I've seen both ways work, but I'm leaning toward hot water because of a 2018 incident where a diver got bent after a cold-water run. Has anyone here switched methods and noticed a real difference in safety or bottom times?

3 comments

3 Comments

hannah3201mo ago

Funny you mention that 2018 incident, I remember reading a study a couple years back about how cold water can actually slow down the offgassing process in your tissues. It basically said the cold makes your blood vessels squeeze up, so the nitrogen takes longer to leave. That alone made me rethink the whole cold water thing. Plus, I talked to an old saturation diver out of Lafayette who said he switched to hot water after his second bend and never looked back. Have you ever noticed a difference in how clear your head feels after a cold water hang vs a hot one?

ivan_murphy801mo ago

Funny enough my last hot water suit decided to leak right on the coldest part of my back, talk about a wake up call. I've been on both sides of this argument and honestly it feels like choosing between getting your toes frozen off or sweating through a wetsuit. That 2018 incident you mentioned sticks with me too, seen enough bent divers to know cold water makes the bubbles just a little too happy to form. Your mileage may vary but I've had way better luck with hot water keeping my core temp steady during those long decompression hangs. Plus the comfort factor alone makes me less likely to rush the stops and make a stupid mistake.

samflores1mo ago

Funny you mention that leak on your back, @ivan_murphy80, because I used to be one of those guys who swore by cold water. Thought it kept me alert and less sleepy during long hangs. But after switching to hot water a few years back, I have not had a single case of post dive joint pain or feeling foggy like I used to. That 2018 story and a close call with a buddy who got bent on a cold water dive in the Gulf really sold me on keeping my core temp steady with hot water.