Exposure protection lesson

[pipedope]

In water much over 90 degrees a resting diver will overheat.
In water over about 85 degrees a working diver can overheat.

Trust me, you don't want a case of heat exhaustion or heat stroke underwater.
It is NOT fun.

In lots of commercial diving keeping the diver cool is an important part of the exposure protection.

 

[Al Mialkovsky]

My core temps lowered pretty good on our last trip to Maui in 77-78 degree waters. After a few days I wished I had a 5 mil.

Then I did the rebreather thing and was totally toasty. Breathing 98.6 degree air does wonders.

 

[DiverDebbie]

DiveMe, I was diving in Kona a month ago, and did 27 dives over 6 days. Using a 3mm suit I was (very) chilled by day 3. Water temps were 80 to 76, depending on the dive site.

I have a 3mm core warmer as well as a 3mm hood I take on these trips, and was toasty warm with those on top of the 3mm suit, even on the last days.

My wife has a White's Tropical Drysuit she switches to when she gets chilled.

All the best, James

Great points about the exposure suits. I thought I'd look like a wuss taking my 5/4 to Hawaii as well as my 3 full, but now I don't feel so bad. I get cold easy and dive dry up here.
So James... what is a "tropical" drysuit? Is it basically a shell that you don't wear an undergarmet with?

 

[fdog]

<snip>
So James... what is a "tropical" drysuit? Is it basically a shell that you don't wear an undergarmet with?

A lightweight drysuit with ankle seals so you can use full foot flippers. Long underwear and a tee-shirt, or, very light fleece as undergarments.

My wife loves hers....I'm next in line to get one...

All the best, James

 

[Al Mialkovsky]

I was tempted to go dry with the tropical but another instructor at our shop went one and I decided I'd do dry only in cold waters. I love dry but sometimes it's a hassle.

 

[DiverDebbie]

I was tempted to go dry with the tropical but another instructor at our shop went one and I decided I'd do dry only in cold waters. I love dry but sometimes it's a hassle.

Well I learned something, as I never knew a tropical drysuit existed... but I'm with you Al... I plan to leave the drysuit diving for cold waters. I'm looking forward to getting *wet*... and not unintentionally by a leaky drysuit! lol. The worst part I find about diving dry around here is in the summer before and after a dive. Everyone has to time gearing up so you can do it quickly and hurry to the water before dying of heat stroke... and unzipping and getting out after a dive is top priority. Nope, I could not even imagine enduring a drysuit in Hawaii !! ...but hey, to each his (or her) own... whatever works

 

[bluemagoo]

Body heat is lost not only from skin exposure but also from exhaled air. In the initial stages of exposure, the body reacts by constricting the peripheral vascular system. But the humidity of exhaled breaths not only continues to carry away heat, it also carries heat away directly from the core areas of the body. This is why rebreathers are warmer; the exhaled heat is recirculated in the loop rather than dumped into the sea. Lost core temperatures are tough to recover; if the person is alert with intact gag reflexes, sipping warm fluids help (not coffee or booze or other diuretics since these encourage more heat loss with the pee) as well as warm packs to the armpits, groin, and abdomen. In genuine danger-zone hypothermia, warmed intravenous fluids, enemas, and humidified O2 may be needed to keep the furnace from going completely out -- warming the extremities must be done carefully because of the risk of circulatory collapse/cardiac shock from suddenly shunting warmed blood away from the core where it's most needed and simultaneously circulating still-cool peripheral blood back into the core.

 

[Shaka Doug]

You'll find that many of the local pro divers here on Maui go with a 5/3 full suit if they dive a lot. I personally have stuck with a 3/2 for almost a year straight and I'm not getting cold but I do remember my old 5/3 was extra nice. Full suits provide much more than just thermal protection. Coral scrapes, jellyfish stings, and sunburn are greatly minimized with a full suit. One thing that you can do (that many people overlook) to help keep you warm in an even releatively thin suit is to make sure you flood the suit when you first enter the water. This thin layer of water within your suit is quickly heated up by your extra warm body and it will help insulate you throughout your dive. I make it a point to have us all flood our suits right away when we enter the ocean and it's unusual to hear someone complain of being cold. It keeps my guests from having to "Shi Shi" in my Shaka Suits too!

 

[DiveMaven]

Thanks for all the responses, it's good to know that it isn't that I'm a whimp, but instead pretty darned normal! <ha ha ha> My husband is teasing me that now my 3mm will only be good for Eastern/Southern Caribbean and summer Keys diving. My response is that I guess we'll have to head to the Keys next summer so I can wear my 3mm!

I'm in the camp that believes that full suits are important for all exposure protection, not just warmth. Although I strive hard to always have excellent buoyancy control and stay off the reef, etc., you just never know when **it will happen.

Doug, I always flush my suit when I hit the water. Helps with descending easily by getting rid of any air pockets that might be lingering in the suit.

 

[jdf]

DiverDebbie,

From the wife of Fdog, I originally bought the dry suit because we do an Aggressor trip every year and I was tired of putting on a wet and sticky wetsuit every dive. By the end of the week, it was pretty nasty. This year on the Kona Aggressor, I switched back and forth from my 3mm and my drysuit, giving my 3mm time to dry, therefore more comfortable to put on. I really like the dry suit but it has its pro's and cons. Pros: Staying dry, staying warm and being able to put on or take off layers, easier and faster to get into, great for night dives when you don't want to have to shower before evening festivities. Cons: If it is hot and humid on the surface, you get pretty warm putting on your undergarments before getting in the water, its very comfortable, but a little less flexible. I am finding it has alot more uses than just 'tropical diving'. I have used it at Lake Tahoe with 60 degree water and was very comfortable. I think with a thicker layer of fleece, I will try it in Monterey, CA water temp of about 54 degrees. It has an easier learning curve than a full drysuit because you don't have the 'getting air in your feet' problem.

If I were doing alot of diving in the tropics, I'd definitely get one.

Janet