Steels and Wetsuit Compatability

[MacLeod]

I don't have much experience with steel tanks. I have used them only a couple of times a year ago while using my drysuit.

Certainly the lift redundancy of a dry suit is unquestionably necessary for steel doubles, but what about singles? Can one dive single PST 120s (HP/E7) or PST 130s (E8/LP104) comfortably in say a 3mm wetsuit?

Buoyancy charactersitics (lbs):
120: -1.3 (empty) -10.3 (full) Weight: 36.6 empty
130: -4.8 (empty) -14.6 (full) Weight: 42.2 empty

I have heard some say 120s are O.K. as singles whereas 130s are not...is this true? Is there a difference...or are both O.K. or are neither acceptable?

Really appreciate you help...thank you!

 

[notabob]

Well, a lot depends on the suit you're using and your physiology. How much weight do you usually need in that suit with an AL tank? Subtract the bouyancy difference between the AL tank and the steel one, and then think about whether you are capable of swimming that weight up in case your BC fails. If you can't then seek a lighter tank.

For example, say in a full 3mm suit with an AL80 you would need 12lbs. Now, you subtract the ~4lbs of empty bouyancy of an AL tank (4lbs positive when empty), leaving you with 8lbs of weight still needed. Then you subtract the ~5lbs of empty bouyancy of the 130 tank, leaving you with 3lbs of weight still needed on your belt to be neutral. So you should be good with a 130. Now, if the BC happens to fail at the beginning of the dive when the tank is full, you may still have to fin pretty hard to swim it up, or at least to your ascent line.

-Roman.

 

[Genesis]

are fine in a 3mil. I dive 'em all the time.

The 130 might be a problem...

 

[drbill]

I almost always use a steel HP120 tank (so I can get two good dives out of each fill). I wear it with my 7mm, my 3/2mm full and my 3mm shortie with no apparent problems. I often swim it up from depth since I keep my BCD deflated or very slightly inflated to remain stable when I videotape.

Dr. Bill