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March 30, 2009

The importance of picking the right dive suit

When I first started diving, I didn't think much about water temperature. The pool where I did my training dives was comfortably warm, and I was far too occupied with figuring out how to breathe and move underwater to worry about being hot or cold. When we selected our rental gear at the dive shop for the certification dives in Folsom Lake, I picked whatever fit as opposed to checking the anticipated temperature of the lake and then getting the appropriate gear. And when I worked on our scuba website and wrote a section on exposure suits, the insulation guideline table from Carol's NAUI course materials meant little to me.

That table said to wear a dive skin in water 85 degrees and above, a thin wet suit for 75 to 85 degree water, a 5-7mm wetsuit for 55 to 75 degree water, and a dry suit for temperatures between 35 and 55. So when it came time for me to get my own wetsuit, I figured 7mm was best as it provided the widest range of protection.

The Telos 7mm suit I picked as my general purpose dive gear certainly did provide good protection, but I soon realized that there were drawbacks. The 7mm material is thick and bulky, making it difficult to pack the suit on trips. The suit was very difficult to put on and I was usually exhausted before I even got in the water, just from getting into the darn thing. And even a bit of sun or exertion on dry land led to overheating.

Still, I wore the 7mm suit on all my early dives, including the rivers and springs of Florida (71 to 73 degrees) and Lake Tahoe which was usually 66 or so on the surface and then ranged from a chilly 48 degrees at 110 feet to the mid to high 50s on most dives. Once I was in the water I felt just fine in Florida, and really wasn't too cold in Tahoe. Getting into and out of the suit, however, was a constant pain, and often what I remembered most. I thought working up a major sweat and being exhausted from putting on the wetsuit was the norm. I did buy a second 7mm suit, one that fit me better and was more stretchy. That made a substantial difference.

I bought a 3mm wetsuit for my August trip to Honduras where the water was usually 84 to 86 at the bottom. That was perfect and there probably wasn't even a need for a suit as the weather was hot and sunny. Putting on the 3mm suit was infinitely easier than the thicker suits. The 3mm suit also dried much quicker and took up much less space in my luggage. After those wonderful dives in tropical waters I thought I had it all figured out. 3mm worked in warm water, and as soon as it got a bit colder, or even quite cold, 7mm would do the trick.

Then I found out it wasn't that easy. When we returned to Honduras in December, the water was still 78 to 80 degrees at the bottom, and usually 80 to 82 at the surface. I thought that was plenty warm enough for wearing my 3mm suit, but I was usually cold. I also found that overcast skies and wind can make a huge difference. It's one thing to emerge from the water and into the warm sun, and quite another to come up to wind and rain. Wind, especially, can be brutal on an open dive boat, and somehow the difference between a sunny and a gray, overcast day is huge, too. I was so cold that I bought a diveskin to wear underneath the 3mm suit, but found that it hardly made a difference. I also bought a Shammyz jacket to keep warm on the boat.

The wreck diving trip to San Diego then showed me that even a 7mm suit with thick boots, thick gloves and a hood was not enough to keep me warm in 50 degree water, at least not when I was staying down in that cold water for 30 minutes at a time. It felt brutally cold, to the extent where I could not enjoy the dives and had to skip some. I felt that the gray, dreary sky contributed to feeling cold once I was back up. I tried diving with the skin under the 7mm suit, but it made little difference.

What I learned is that there's nothing like personal experience when it comes to picking the right suit to wear on your dives. There may be guidelines, but you need to experience how it feels to you and what your personal comfort level is. I really thought that a couple of suits would cover the whole range of water temperatures you're likely to encounter on typical dives, but, at least for me, that's not so. Knowing what I know now, I'd have bought a 5mm suit for my December trip to Honduras, and I am now contemplating dry suit certification so I'll be able to enjoy my next cold water dives.

Why not just tough it out? For some that my be a solution, but I don't think it's worth it. Dive vacations and dive trips are expensive, and not being able to enjoy dives, or even having to skip dives, because of being cold makes no sense at all. As far as I am concerned, it can even be dangerous if you find yourself shivering underwater instead of paying attention.

I should also mention that the type of wetsuit you wear makes a BIG difference on your buoyancy. That's another thing I only learned through experience. I thought there couldn't possibly be much difference between a 3mm and a 7mm suit, but there is, and you have to compensate by adding or subtracting weight from your weight belt or your BC's weight pockets. Even gloves and a hood can make a difference.

Posted by conradb212 at March 30, 2009 03:16 PM