"Riding your Computer Up" vs. "Lite Deco"

[Diving Dubai]

Is there no course that specifically teaches back gas deco considerations? Does some common-sense organization like BSAC cover this?

@KenGordon & @Edward3c Should be able to give you more information on this. I crossed over to BSAC and took the Dive Leader Course (PADI DM level) from being a PADI rescue so didn't take the earlier training

BSAC tables (nitrox and Air) both include Decompression stops (and your final pressure group) on each table. Certainly I had to complete a planned deco dive as part of my DL (back gas only). Learning the BSAC tables wasn't as easy as I assumed - they are quite detailed taking account of different air pressures etc.

I believe that Deco diving on a single gas is taught at Sports Diver (The first level Ocean Diver is equivalent to PADI OW+AOW) I say believe because I don't have the course books for those courses.

For Mixed gases there is certainly a separate course (Accelerated Decompression Course)

 

[KenGordon]

Is there no course that specifically teaches back gas deco considerations? Does some common-sense organization like BSAC cover this?

Yes. The BSAC Sports Diver course covers back gas deco. It is the qualification that almost all club divers will reach. The 20m limit on Ocean Diver isn't really enough for British diving. Sports Diver includes significant rescue skills as well as deco, plus some starter organisation stuff. The deco is back gas only, taught with tables. These are quite aggressive tables and educational in themselves. It includes altitude diving and particularly travel over hilly terrain.

As mentioned above there is the ADP course which covers use of rich mixes for deco. Many fewer people bother with that.

This training results in a different mindset to the AOW style training. Divers are not afraid of getting into deco. They have done stops in training, people do it regularly and they see them walk away. It is a tool which is available.

Keep in mind that very few people get trained to sport diver in a weekend or two. It can be done but that is not the usual way. As a result there is quite an opportunity for getting the idea of how stuff works outside of formal training.

 

[DevonDiver]

You know, you don't need technical training to figure out your RMV. Nor to run a dive profile in Multi-Deco and figure out how much gas you would need, even for a deco dive. Nor to understand what Gradient Factors are.

Yep, I know. You can learn it online from a chat forum...

And if someone believes that's all they need to learn before bypassing tech training en-route to conducting decompression dives... then good luck to them.

I just don't see anything AUTOMATICALLY, INHERENTLY wrong with someone that has no formal tech training doing dives with a few minutes of deco. You implied that anyone doing that without formal training is foolish. I don't think that's fair. I think it's entirely feasible to learn how to do that safely on your own.

Define 'safely'. . . .

 

[DevonDiver]

You are arguing beyond the scope of this thread again.. . If you re-read my OP, you will see that the only deco that I'm discussing is the deco requirement one gets if one replaces a purely recreational dive (done aggressively using an aggressive DC) with a highly conservative DC/algorithm/plan that will allow for deco. Same dive profile, same dive. Same thinking put into practice daily around the planet: Buy an aggressive DC and max it out under NDL rules.

How is it the "Same dive profile, same dive", when one individual does deco stops and the other doesn't??

The profiles would be very different? No?

One would be curved with staged decompression, the other would be straight-line, direct ascent.

Consider the simple notion of comparative ratios of decompression time versus bottom time between the two alternatives.

The basis of the issue seems to that of 'disposable decompression'. That... because some table or algorithm exists somewhere that 'allows' a given depth/time as a no-stop dive... it therefore becomes an acceptable mindset to consider a deco plan as a cast-away option, rather than an obligation that the diver commits to. Genius...

Remind me... what name do we give to a non-mandatory stop performed for conservatism only?

What's suggested is really pointless. Just do your aggressive bottom phase and voluntarily increase the duration and/or number of your safety stop/s to add as much extra conservatism as you'd like. Job done!

Why the compunction to fudge faux-deco? Because someone is unable to do something unless their computer 'tells' them to do it? You see how pathetic that sounds...?

 

[DevonDiver]

Perhaps the real title of this thread should be:

"How to hack your dive computer to do more conservative safety stops after aggressive dive profiles".

Because, let's face it... we're not talking about committing to real, mandatory, decompression... are we?

Just lobby dive computer manufacturers to add more conservative safety stop options as a standard.... honestly, it'd probably get a lot more usage than the existing conservatism settings. People do love those fancy functions...

 

[Diving Dubai]

I never enter Deco

I manage to avoid it, by attaching my computer to a DSMB and sending it up to a more acceptable depth while I carry on with my dive at depth.

 

[Storker]

Just don't use a Suunto. It'll freak out from the fast ascent and penalize you on your next dive.

 

[Diving Dubai]

I do use a Suunto, To overcome it penalizing me, I clip it back onto a reel and drop it back to 5m for the trip back. There's always a work around these things

TO clarify, my last 2 posts are tongue in cheek to add some humour here, I don't really do this

 

[w3dge]

I'm not sure I'm getting this...

We have some experienced/serious/expert/*insersuperlativehere* recreational divers who are experienced/expert/etcetc enough to know what they're doing whilst manipulating their DCs to get the dives they want. Great. So why do they have to carry a conservative DC with them, intentionally push it into deco status, just so they can follow its ascent profile? (Obviously totally disregarding the fact that a recreational DC doesn't really give you an ascent profile...)

Surely if you're that experienced/serious/expert you can dive to the conservatism that you want, and follow your own ascent curve up?

And if you want to 'draw a conservatism line in the sand', then draw that line where you want it, and dive to it. Don't draw it somewhere and then totally disregard it by stepping over it. How far do you step over it?

 

[Storker]

if you want to 'draw a conservatism line in the sand', then draw that line where you want it, and dive to it. Don't draw it somewhere and then totally disregard it by stepping over it.

Totally agree, and this is basically what I was trying to say some 80 posts back, in post #68.