Dry Suit Squeeze

[scuba_frog]

I have had my USIA dry suit for about 2 years. I do have the dry suit certification. Have not used it too much mostly because it used to leak like crazy. It is now fixed. After diving in it twice, after I get to about 20', the squeeze is so tight, I find it hard to breathe. I add air to the suit, then I start to ascend. I'm 6', 275# and wear 30 lbs of weight with the dry suit...much less diving wet. If I continue to add air, I will have to add weight to compensate. Bad move I think.

Few questions:

1. Is this normal.
2. How else can I eliminate the squeeze.
3. Would a neopreme suit like a SeaSoft be any better...if so, being neopreme, would I need more weight to compensate for the additional buoyancy of the neopreme
4. Does the excess "wrap" material of the USIA add to the problem.

Thanks for your help. If I can shed more light on this let me know.

 

[docmartin]

1. no. you need more weight unless you have air in your bc/wing that you could vent. you may be able to alleviate the need for more weight by choosing clothing with less loft (no idea what you wear under your drysuit).
2. only way is to add air
3. i don't think that neoprene is any better
4. No

 

[Peter_C]

If you do not already, diving steel tanks makes a big difference. I keep a couple of extra pounds over my minimum weight requirement for warmth, not so much squeeze, but they are directly related. What kind of BC are you using? Weight belt also or?

 

[spectrum]

1. If you are down at 20 feet and neutral you have probably added considerable air to your BC. Adding air to your suit for loft (squeeze relief and warmth) will make you more buoyant and is perfectly normal. This will make you rise. What you need to to is release some BC air as you put air in your suit. If you see this coming you can add some air to the suit instead of the BC and not even need to vent your BC. This is what learning to dive a drysuit is all about. It's one more air bladder to maintain. Most prefer to have the majority of their buoyancy coming from the BC, it's easier to manage.

Since you suit now represents a source of buoyancy you MUST manage it on ascent. Have the vent valve open, manipulate it to make the valve the high point periodically and go slow. (It vents much slower than your BC can)

2. Adding air is the only way to relieve squeeze.

3. A neoprene suit is not very different. I happen to be OK in mine to about 30 feet but sometimes I add some air around 20 feet. Since the neoprene suit rebounds to full buoyancy at the surface it tends to require more in the way of weight. This is mitigated somewhat by the fact that you need to wear less for undergarments.

4. I'm not familiar with that suit but if it's what it sounds like, no.

5. What was covered in your drysuit certification class?

 

[all4scuba05]

The drysuit isn't to keep you warm. It's to keep you dry which in turns helps to keep you warm. The undergarment you wear is what insulates you from the cold water around you. Air is a great insulator Without it in your suit, the undergarment will be compressed and lose quite a bit of it's insulating qualities. As you know you will also feel too much squeeze.

You have to accept the fact that because you need insulation and air in your drysuit, you will also need weight to keep you under during your safety stop with <500 psi of air in your tank.

Don't get hung up on trying to drops weights. First get what you need to feel comfortably warm. Then get get used to putting just enough air in the suit to remove the squeeze. Aftr that see how much weight you are over or under by.

 

[AUTiger]

What kind of undergarments are you wearing? Warm garments increase your buoyancy, requiring more lead.

On a different note, supportive underwear made the squeeze much more edurable - kept the frank and beans in a good position. I use spandex/lyrca swim shorts. My first dives were in boxers and those were quite uncomfortable.

I'm a new dry suit diver, but 30 lbs seems pretty lean. I'm 5'9" and use 30 lbs with 200g fleece jumpsuit and an aluminum tank. I increased about 8-10lbs going from a 5/7 wetsuit and hooded vest to my trilam DUI TLS350 drysuit. I moved to a steel tank and took 6 lbs out of my BC.

David

 

[Web Monkey]

You can't violate the laws of physics.

Warm = Thick Underwear = More Air in the Suit = More Water Displacement = More Weight to Sink.

You need to do a buoyancy check, just like you do with a wetsuit.

Put on all your stuff, vent your suit and start adding weight until you just sink with an almost empty tank.

You might want to add a few more pounds to whatever you need, since some DS exhaust valves need a little more pressure differential to vent.

Whatever weight you come up with, it's what you need. It doesn't matter if it's 10 pounds or 50. You need what you need.

I will say that if you come up with anything significantly more than about 20 pounds, that I would recommend a weight harness like the DUI Weight and Trim. Weight belts are a real pain in the *** when you start loading them up, and most integrated weight systems aren't reliable with a lot of weight.

Terry

I have had my USIA dry suit for about 2 years. I do have the dry suit certification. Have not used it too much mostly because it used to leak like crazy. It is now fixed. After diving in it twice, after I get to about 20', the squeeze is so tight, I find it hard to breathe. I add air to the suit, then I start to

 

[under water]

..I'm 6', 275# and wear 30 lbs of weight with the dry suit...much less diving wet. If I continue to add air, I will have to add weight to compensate. Bad move I think.

You need more negative buoyancy.
As someone mentioned, you can get some of it by using steel tanks. You can add weight to get the rest.
Air is your friend in a dry suit, It's what helps you keep warm.
You might try opening up your shoulder valve a bit more to allow for more control of the squeeze. As was mentioned. put enough air in the DS as your go down to get rid of the squeeze and use the BC to adjust buoyancy.
Start off over-weighted a bit. You have plenty of lift if you need it.
It is a bit trickier than a wet suit.

 

[aowdan]

i've only done 3 DS dives, but i have to mess with my weight belt to get a little air to my feet to relieve the squeeze.

dano

p.s. yes i'm in key west, the dry suit is only for training

 

[dannobee]

Adding air is a good thing. Weight comes along with that. If you're feeling a squeeze, add air to the suit and not to the BC.

I agree with some of the other people; get a steel tank and a stainless steel backplate if you want to take off a lot of weight.

30 lbs seems awfully light for someone of your weight, especially considering you're feeling a squeeze and floating up when you add air.

A starting point is 10% of your bodyweight and 10 lbs (assuming an AL 80 tank and a standard jacket style BC). Do a pool check to dial it in further.