'Recreational' deco planning

[MATTBIN]

Originally Posted by And

Because the 'deco' it states is what I would do on a 'no stop' dive. 3m/min and then 5 mins from 6 to the surface. It will also depend heavily on the Gradient Factors (GF) you have used. When using GF's I use 30/90.

Andy

30/90 is a bit more agrresive than 20/80, I'm an old man!

Matt

[And]

Ah, well, it just goes to show that taking deco advice off the internet is fraught with danger, as what works for one person might not work for another. Using dive computers has similar circumstances, in that you don't necessarily know whether the manufacturers profile will work for you or not.

My advice is worth exactly what you paid for it

Andy

[MATTBIN]

Andy
stop quoting Vic, Chasey will have a heart attack!

You're right but its nice to know that what I might use is a little more conservative than all you young bucks.

Nothing wrong with a bit of padding.

Matt

[Mark Chase]

In a recent study published in Diver mag they found the Suunto Vytec to mimic most accurately the Canadian no decompression limits for diving. These are considered the benchmark of accepted no decompression limits. Some would say, great I own a computer that has minimal conservatism. I would say fine as long as you understand the implications of that.

Just flying the computer is a great and liberating way to dive but you should take he time to understand how it works. If you get bent its not the computers fault as most people claim. It is totally the divers fault. A sad fact not properly emphasised on basic training.

Matt.

The deco profile you put forward is fine nothing wrong with it but the dive is a virtually no deco dive your just adding safety as well you should. The young whippersnappers with bodies like Greek gods, blood free of alcohol and cholesterol and lungs free of tar would be running GF100/100 profiles or worse. 100/100 would give 1min at 6m for 25mins at 35m on 30% Nitrox. QED it’s not a deco dive on pure Buhlmann. Unless your body falls into the above groping I would err on the side of caution and bung in a few stops

ATB

Mark Chase

[MATTBIN]

Mark
we intend to, I think we just wanted confirmation or at least concesus that the profile we proposed want going to bend us like a spring.

I know you are dyslexic, but sometimes your spelling just cracks me up. I dont think I'm in that particular 'grope' you mention above. Pure Allo Allo.
Brought a real smile to my face.

Cheers
Matt

[daz]

There is a really good article in DAN alert magazine this month about a study on deep(er than normal ) stops on 25m dives using doppler tests.

They got a group of divers to run a number of different profiles with different ascent rates. There were specific parameters such as two 25m dives with a 3 hour and something surface interval.

On one profile they did a straight ascent to the surface using a number of different ascent rates (exception being 18m a min IIRC which they put a 3min stop in due to the possible risks).

On others they did stops at 15m for 5 mins and 6m for 5 mins with differing ascent rate.

In summary, the 10m a min ascent rate with a stop of 5mins at 15m and 5mins at 6m produced the lowest doppler reader, 3m a min with the same stops was slightly higher.

Good reading for anyone who is interested.

They also have lots of other articles on their website which are somewhat interesting.

http://www.diversalertnetwork.org/research/index.asp

Daz

[Noel Johnson]

Plan the depth on the PADI tables and dive the plan just in case the computer fails. I have gone into deco before now and followed the computers (Vyper) schedule but it's rarely been anything above a 6 minute ascent time (including the 3 min safety stop).

To this date I have not done a staged decompression dive or a course so a lot of this has gone over my head I'm afraid - although the road is going to be trodden soon with me starting the IANTD advanced nitrox course as I would like to get more technical and spend a little more time on the wrecks I enjoy.

[Woz]

Oh and if it's vaguely deep I also chuck in a couple of Pyle stops for good measure.

[Ian@1904]

For a 35m dive I would plan it on the computer (Vytec) and then extend the dive until 10 minutes of deco time is shown up. This then also shows me my expected air-air integrated.

What I have done is to create my own mini diving tables using the Vytec, printed and laminated.

I then have a plan for for if things go pear shaped.

For diving less than 30m I mainly rely on the Vytec, as I will usually be cold before hitting deco limits.

[Garf]

I would fly the VR3, pad it out as usual, and have tables in pocket as always.