Low SAC rate and hypothermia

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Really good ideas, Pete! I don't think anything would have been enough to save the day in the conditions of last weekend, but under more controlled/expected circumstances, your ideas should be enough to make it work. You're right -- the interval between getting the suit off and getting thoroughly dry is absolutely the worst. Actually painful last weekend. :(


You don't need MORE wetsuit, you need a BETTER wetsuit! Does your have zippers and a separate hood and a nylon lining on the inside? All these things reduce the thermal protection...

Yes, I have zippers at the wrists and ankles. The suit would be impossible to don and doff without them. Yes, on the separate hood. I didn't know about hoods integrated with wetsuits when I ordered this one. The separate hood ends up being good sometimes because conditions may allow for use of a beanie instead, which helps when I have an instructor that I need to be able to hear. There really aren't any conditions where going bare-headed makes sense for me. Maybe a single dive per day in the Caribbean, but who goes there to get in the water only once a day?? Not me. :) When I'm wearing the hood tucked in, I notice practically no "breeze" coming through the neck.

No, on the nylon lining; the inner surface is nice, shiny blue stuff that dries in minutes.
 
Thanks, stargost. The book looks great, and I'm going to get it used from Amazon for a few bucks less (shipping from the site you linked is really high).

dumpsterDiver, I just realized there kind of is a nylon lining involved with my wetsuit -- it's the diveskin I wear under it. Again, absolutely necessary for getting the suit off and on.
 
Thanks, stargost. The book looks great, and I'm going to get it used from Amazon for a few bucks less (shipping from the site you linked is really high).

dumpsterDiver, I just realized there kind of is a nylon lining involved with my wetsuit -- it's the diveskin I wear under it. Again, absolutely necessary for getting the suit off and on.

Sorry but you are absolutely wrong, you do NOT need a skin to put on some wetsuits. It is not your fault. Most scuba instructors don't know about this either.

A freedive suit has smooth rubber on the inside, no nylon lining and you do not wear a dive skin under it.

Instead, you use a lubricating fluid to don the suit and it is MUCH easier to slide the suit on. You do NOT need zippers ont he ankles and sleeves!

The nylon layers allow water seepage and certainly do not enhance flexibility of the suit.

Most freedive suits have only one layer of nylon and it is typically on the outside, maybe your suit is like that, not sure what a blue lining is.

Also, your comment about a beanie hood is very telling. Beanie hood is for warm water. In general you want to wear the least amount of wetsuit and get the most thermal protection. This simple fact means that you absolutely want to wear a good, well fitting and thick hood if heat loss is an issue. A good thick hood only adds a small amount of bouyancy relative to an entire suit. So if you are getting cold, the first thing to ditch is the beanie... actually it might be advantageous to wear it OVER your other hood. If you must dive with an inefficient scuba hood then get a hooded vest. In cold water, with a scuba suit, I often wear a 3 mm hood vest and then a separate 5 mm hood over top.. It preserves neck flexibility,is warm and resonably comfortable.
 
Also, your comment about a beanie hood is very telling.

Not necessarily, given that I only wear it when conditions are so warm that others are diving with light exposure protection (if any). I got snookered last weekend because the water ended up being 10 degrees colder than I'd been told. That's the only time I've gotten into trouble with the beanie, because happily, even I can dive in 80 degree water on a 90 degree day without looking completely like the Michelin Man (as long as it's only one or two dives).

I hear what you're saying about wearing the least suit possible. Experience has shown that I'm better safe than sorry and just wearing the 7 mil, or at least having it with me if I get brave and try the 3/2 (heated water at Mt. Storm). I tried the 5 mil hood with the 3/2 suit and didn't find that it bought me enough improvement to matter; only bumping up to the 7 mil does that.

True, I didn't know about using lube instead of zippers to make a heavy suit donnable. Unfortunately, the $500 has already been spent on the one with zippers.

I don't think that improving my neoprene situation is going to result in substantial lengthening of my local dive season, which is the ultimate goal. I can get better at staying warmer during the six weeks or so that I can dive locally, but I think it's going to take a Big Move to lengthen my season, and I think that means dry suit.

Fortunately, I've at least gotten the setup workable for the annual, four-dive-a-day liveaboard trip. That's working out well, though gearing up is time-consuming. The next challenge is to be able to get in the water around here before mid-July and after August.
 
How about a semi-dry suit?

I ALWAYS get cold. I was in Thailand a month ago and was diving with two wetsuits to keep warm.

What you eat makes a difference (especially in my case, as my wife and I are vegetarians).

So, here (in Barcelona) everyone wears a semi-dry 7mm.
 
Semi Dry is nice, but as mentioned the best investment you can make is in a good quality hoodie.
 
https://www.shearwater.com/products/peregrine/

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