Ascending in a Dry Suit

[Nick Stephens]

Hi Guys,
This question goes out to people who use their Dry Suit for buoyancy.
On ascending from a dive, PADI say swim up with your shoulder dump raised to vent the air. I find when I do this air is released too quick and I end up being to heavy to ascend comfortably.
Does anyone do this, or do you just swim up and vent occasionally to control the ascent? Maybe I'm not doing it right?

 

[sealkie]

sounds like you are using too much weight

 

[scubasean]

Hi Guys,
This question goes out to people who use their Dry Suit for buoyancy.
On ascending from a dive, PADI say swim up with your shoulder dump raised to vent the air. I find when I do this air is released too quick and I end up being to heavy to ascend comfortably.
Does anyone do this, or do you just swim up and vent occasionally to control the ascent? Maybe I'm not doing it right?

There are a few ways to do this, IMHO. I presume your dump valve is adjustable...If so, you can crank it down a notch or two to vent more slowly.

Or, as you say, you can vent less frequently, raising your arm as needed for a slow ascent...

If you are overweight (easy to verify) then the solution is obvious...

Good luck!

:banana:

 

[String]

Either adjust the dump valve, alter your body position in the water or do what i did - fit a nice cuff dump instead.

 

[MechDiver]

Hi Guys,
This question goes out to people who use their Dry Suit for buoyancy.
On ascending from a dive, PADI say swim up with your shoulder dump raised to vent the air. I find when I do this air is released too quick and I end up being to heavy to ascend comfortably.
Does anyone do this, or do you just swim up and vent occasionally to control the ascent? Maybe I'm not doing it right?

IMO this is one of the reasons not to use your drysuit as a BC. But, if you must follow the Padi line, however backward it is, then adjust your exhaust valve so, while ascending, you meerly have to raise your arm when you feel yourself getting light. Once you have more experience using the suit, it will become much easier to know when, and how much, to vent.

I would also strongly advise you to learn to use your BC for buoyancy control, as that is what its designed for, while your suit is not.

MD

 

[Snowbear]

Venting a drysuit on ascent is the same whether you're using it or the BC for buoyancy. Yeah, PADI says "swim up." I've found ascending horizontally, burping enough gas out of the suit as needed to control the rate and still be able to stop the ascent, works much better. Takes practice, though

 

[Rimp]

I don't have a lot of experience diving dry yet, but have learned a few things.

Air in your drysuit is very slow to vent, and difficult to control, where venting from a BC is much faster and easier to control.

The suit can hold alot more air, so if you get into an uncontrolled ascent, it can be more difficult to recover from it. Especially with a slow exhaust valve. A BC has a much more limited air mass and is fast to vent.

If you are using your suit as a BC, you should have a cuff dump to make it easier to control the venting. Still not recommended.

A cuff dump is not ideal when using a BC as your buoyancy control device since both your suit AND your BC will vent everytime you raise your arm to vent the BC. For use with a BC it would be better to have the exhaust valve on the shoulder.

Of course there are many variations and themes possible with suits/BC/exhaust valves to the above is only a very general thought. I'm sure it's possible to get used to any system given enough time.

I won't be using my suit as a BC, i know that for sure.

 

[MechDiver]

Venting a drysuit on ascent is the same whether you're using it or the BC for buoyancy.

No, its not. Burping a suit that is not used for buoyancy should not affect your buoyancy as you should have very little air in it. Unless, or course, you let it build up to the point where it would be an issue.
You would also expect to have more air in a suit used for buoyancy, all other things being equal.

Don't make the issue any more difficult for a new user than you have to.

 

[MechDiver]

I don't have a lot of experience diving dry yet, but have learned a few things.

Air in your drysuit is very slow to vent, and difficult to control, where venting from a BC is much faster and easier to control.

The suit can hold alot more air, so if you get into an uncontrolled ascent, it can be more difficult to recover from it. Especially with a slow exhaust valve. A BC has a much more limited air mass and is fast to vent.

If you are using your suit as a BC, you should have a cuff dump to make it easier to control the venting. Still not recommended.

A cuff dump is not ideal when using a BC as your buoyancy control device since both your suit AND your BC will vent everytime you raise your arm to vent the BC. For use with a BC it would be better to have the exhaust valve on the shoulder.

Of course there are many variations and themes possible with suits/BC/exhaust valves to the above is only a very general thought. I'm sure it's possible to get used to any system given enough time.

I won't be using my suit as a BC, i know that for sure.

Outstanding :dazzler1:
Good post!

 

[tel-scuba]

MechDiver is right. If you use inflate your drysuit only to the point of relieving the squeeze (and not for buoyancy), then buoyancy changes on ascent shouldn't be a big deal. It's MUCH easier to conrol the buoyancy on ascent (or any other part of the dive) with the fast-dumping BC.