'Recreational' deco planning

[tom]

How do you plan your deco on 'non-technical' dives?

I'm talking about fairly standard sports diving, on a single gas (air/nitrox), with a limited amount of deco. The impression I have is that most people simply jump off the back of the boat and fly their computers, and begin their ascents when they have clocked up a few minutes of stops.

For the purposes of this question, let's say the dive in question is a wreck in 35m (to seabed) and you want about 25 minutes bottom time. You are diving on 30%. The wreck is a few metres proud, so you'll be spending some but not all of the dive at max depth.

Which of the options in the poll best describes what you do?

This question only applies to situations where you are planning to incur a decompression requirement - NOT dives within 'no deco limits'.

[And]

Theres no deco on that dive Tom (well, about 5 mins), its just a slow ascent. (Assuming avg depth of 33).

Oh, and I do ratio deco

Andy

[tom]

Originally Posted by And

Theres no deco on that dive Tom (well, about 5 mins), its just a slow ascent. (Assuming avg depth of 33).

Maybe - it's over the no-deco limits on PADI and SAA Buhlman tables though, and probably most dive computers. Dives with something like 5 - 10 minutes requirement are what I'm thinking of.

[And]

No worries, here is a 'minimum deco' table you might like to use. It has a 'mandatory' deco of a slow ascent with a final 1mtr/min ascent from 6 mtrs. That might suffice for those types of dives using nitrox.

http://dir-diver.com/en/download/

Andy

[Janos]

I don't dive hugley deep. So if (say) doing a dive to 35m, then, because I've planned the dive in detail with tables and gas consumption calcs several times in the past, I don't feel I need to do it again. Consequently I feel confident about just jumping in and heading up when I get down to 80 bar on twin 12s (I have a high SAC).

Laters,
Janos
PS - I also carry bail out tables just in case.

[Conor]

I have to admit I have never intended to do a Deco dive, but, while I'm monitoring my no-deco time I may decide to overstay a little if the dive warrants it and my gas will last safely (this has only happened a handful of times).

To be totally honest I have a rough idea in my head of my no-stop times, and will occassionally confirm them if a dive sounds a little out of my usual range. I confess I am quite reliant on my computer, but I would start the ascent immediately if I had a computer failure and do the amount of stops it reported last time I looked plus 5 mins or so to be sure.

This maybe not the best way to dive, but I'm being honest and from my experience I am not alone in this approach

Conor

[ahar]

I generally work out what the no stop time is and decide how many 'minutes to surface' I want depending on the depth, gas, water temp etc. I fly the Vytec (hence the time to surface measure) but have a set of IANTD deco tables in my pocket in case the Vytec blows up during the dive.

I don't take it above '10 mins to surface', which mostly clears with a nice slow (approx 5 m/min) ascent. I know this isn't the most scientific of methods which is why I want to do a Deco proceedures course this year to sort out my half arsed attempts.

Working in IT, I suppose I put more reliance on my computer than I maybe should do.

[Woz]

I've got a Vyper and a Quantum. I'll do the dive running the deco on the Vyper but switch to a pony full of 50% and tell the Quantum that I've done it. So effectively I'm doing a single mix dive but with the additional safety factor of deco on a richer mix. Plus if it all goes wibbly wobbly- both computers tonto, buddy buggered off, brain refusing to think etc then I'll do 5 mins at 9m counting crocodiles then sit at 6 until I'm huffing fumes.

I'm sure if I get more technical then I'll change to something else but I can't see me doing that in the near future. I'm happy at 35m prodding fish and tiewrapping porn to wrecks.

[nigelH]

Originally Posted by tom

How do you plan your deco on 'non-technical' dives?

All dives these days are done on the VR3 with tables in my pocket as backup.

What is a non-technical dive by the way?
Does using Helium in the pool because I don't have a bottle of non-helium diluent make that 'technical'?

nigelH

[chrisch]

Originally Posted by nigelH

Does using Helium in the pool because I don't have a bottle of non-helium diluent make that 'technical'?

nigelH

Naaa... just means you have too much dosh....

Chris