Recreational Scuba Deco Diving

[tursiops]

OK, have I got it right?
Nineteen years ago you were were diving air with independent doubles, solo, Navy tables, 15 mins deco max, depth not stated, SAC not stated,

 

[NothingClever]

FWIW - I use the term "TechReational" for short deco 10 minutes or so....

I think 10 minutes is an expanded safety stop.

I use the term "Hollywood dive" for anything that incurs 30 minutes or less of decompression obligation with a single decompression gas. It's easy to be glamourous on those dives.

Adding a stage for a longer BT, a second deco gas and having to watch the clock for air breaks? No longer a Hollywood dive.

 

[rjack321]

OK, have I got it right?
Nineteen years ago you were were diving air with independent doubles, solo, Navy tables, 15 mins deco max, depth not stated, SAC not stated,

You forgot the part about how he quit deco diving because he had kids and is now (roughly) in his mid to late 40s or 50s. Those Navy Tables (and air) are not going to feel so good anymore.

 

[Blackcrusader]

You forgot the part about how he quit deco diving because he had kids and is now (roughly) in his mid to late 40s or 50s. Those Navy Tables (and air) are not going to feel so good anymore.

can always use Nitrox 32%

 

[rjack321]

can always use Nitrox 32%

Or take AN/DP (or similar) and bring 50% or O2. An al30 of either of those is NOTHING compared to the double independent 120s. I mean seriously carry smaller doubles and a deco gas and life is lighter and simpler than 2 giant water heaters of a terrible gas which only benefit is its cheap.

 

[rx7diver]

... I mean seriously carry smaller doubles ... 2 giant water heaters ...

LOL. Yes, those double HP 120's are large (tall). They were/are left over from my Great Lakes diving. I would have preferred my double HP 100's (same 7.25" OD, but 4" shorter) for my MO/AK RSDD diving, but, unfortunately, I had gotten rid of mine long ago in order to purchase my HP 120's.

(Note: The HP 120's are not nearly as large, though, as the double OMS/Faber LP 126's that one of my Michigan dive buddies, an ex-Marine, wore! I am glad I didn't have to resort to using those for my MO/AK RSDD diving!)

rx7diver

 

[Sunn]

(...) 2 giant water heaters of a terrible gas which only benefit is its cheap.

terrible gas with which only 7.800.000.000 humans are breathing everyday....

let's stay reasonable !

 

[rx7diver]

... he had kids and is now (roughly) in his mid to late 40s or 50s. Those Navy Tables (and air) are not going to feel so good anymore.

Not sure it's germane to this thread, but I am 65, soon to turn 66. See my avatar? All the white hair? That's me from a couple of years ago. Much more white hair now. (My daughters are a college sophomore and high school seniors now.)

rx7diver

 

[KenGordon]

Or take AN/DP (or similar) and bring 50% or O2. An al30 of either of those is NOTHING compared to the double independent 120s. I mean seriously carry smaller doubles and a deco gas and life is lighter and simpler than 2 giant water heaters of a terrible gas which only benefit is its cheap.

For short deco obligations there isn’t much benefit from accelerated deco, just a load of extra risk of using the wrong gas. 10 or 15 minutes twice as fast but needing to get and carry rich or o2 fills?

For example, 40 minutes at 30m using 32% give a 14 minute last stop, 50% reduces that to 9 minutes, o2 to 6 minutes. So a saving of up to 8 minutes best way. If you decide to use air for the bottom gas then even using both 50 and o2 is slower.

And what is your lost deco gas plan? Either it is to take gas from your buddy, who had better have brought double, or have back gas to cover the obligation and so either smaller cylinder benefit or you are just in the same place as a single cylinder diver, relying on a buddy.

I understand that the US centric agencies don’t really address this point in the progression from simple entry level diving and complicated “technical” diving and so most of the SB people have never done much non accelerated deco diving. It is not rocket science and can be quite safe.

 

[Blackcrusader]

A lot of people have missed the point of this thread and go around mentioning the use of twin tanks or brining a pony.

"Making a planned decompression dive in a non-overhead environment, using open-circuit scuba, and using EANx for both the bottom gas and a--the only--deco gas." (No stage bottles can be used for extending the dive."