Planned deco on a recreational dive?

[Centrals]

This has how this has progressed...
Planned deco for an untrained diver not carrying a redundant air source or without any degree of actual planning is somehow OK.
- PADI doesn't know what they are talking about.
- Tables are really conservative so you can violate the NDLs and decide for yourself how much of the built in safety factor you are willing to utilize.
- Your computer is too conservative and it's probably different than other computers, so who is to say which is right? Ignore it or better yet set the parameters to eliminate all the conservatism and then still ignore it.
- Missing a deco stop is no big deal.
- BSAC says it's OK for divers to do single tank deco dives, so all of the other organization that say otherwise should be ignored.
- And DAN doesn't know what they are talking about either.

Really?

Doesn't it just make more sense to get the training, proper equipment, plan your dives and dive your plan?

I did just that back in 1998.
As far as I am concerned "planned deco dive" has no place in recreational diving. Any planned deco dive is tec dive. Period.

 

[Storker]

I'm looking into taking CMAS***. If I do, I'll be certified to 40m and backgas deco. AFAIK I'll be "allowed" to do that kind of diving on my single tank gear.

Doesn't mean I'm planning to do that kind of dives, though.

 

[KenGordon]

I did just that back in 1998.
As far as I am concerned "planned deco dive" has no place in recreational diving. Any planned deco dive is tec dive. Period.

Can you not see the risk difference between a dive involving10 minutes air deco and one with an hour of 50% and oxygen?

And is that more or less risky than an NDL 40m dive in nasty vis with old net or fishing line on a wreck with big holes to accidentally swim into?

 

[Freewillow]

Can you not see the risk difference between a dive involving10 minutes air deco and one with an hour of 50% and oxygen?

And is that more or less risky than an NDL 40m dive in nasty vis with old net or fishing line on a wreck with big holes to accidentally swim into?

I am with you on that one. Too often people are "scared like hell" by the word deco. My guess, it has a lot to do with PADI and the US metality no risks, nol liability.

I do not see it as a problem to plan light deco dive on single tank, PROVIDED that you have a reliable buddy and that each diver has enough air for the deco time of both divers. But that requires KNOWLEDGE and THINKING.

Does this relate to TEK, not really

 

[Patoux01]

What they said above...

Too many people scared (or trying to scare others into taking their courses btw, keep an ocean of salt when reading those) by deco. As I've already said, I'm quite happy to skip 2-3 minutes of deco on air... If you take the hit then, you'd have taken it anyway. Also, 3 minutes of air at 3m is not like you need uber-planning for that, like really, we're talking less than 10b of air here.

Common sense is what should prevail in this kind of things IMO.

On a sidenote, this is what has been dived earlier (1965, some of you might recognize them )

Notice the 10 minutes at 40m with no deco stops?

Now I'm not advocating diving those tables, simply getting to realize that, well, maybe we're not so far in the clear as people claim when they say 3 minutes of deco will blow you up, or we would never have been able to use those tables even once (and these were used for a long time).
To those that say a few minutes of deco is a major issue, please have a look at the topic in technical diving about "UTD vs Buhlmann", that's gonna be interesting for most of you I'd say. You can also have a play on most dive planners (subsurface, multideco, pastodeco, ...) and compare a few dives on settings like "VPM-B +2" and "Buhlmann 80/80" and "Buhlmann 40/70". The first of those settings is quire safe, the 2nd is the typical recommendation for air (deco) dives in France/Switzerland (and probably a few others), the last one is around the typical (I believe?) recommendation on trimix dives here (and often used for deco dives with air as backgas).



P.S: I had made a very nice and long post about that workshop from DAN, but my computer broke down so it's gone until I get that fixed. It's really worth reading to see that the recommendations about flying aren't all that clear either, and a quick search with "resort diver" or "resort course" should show up some nice quotes .

 

[Diving Dubai]

I'm looking into taking CMAS***. If I do, I'll be certified to 40m and backgas deco. AFAIK I'll be "allowed" to do that kind of diving on my single tank gear.

Doesn't mean I'm planning to do that kind of dives, though.

You won't be "allowed". You will have received training and knowledge that gives you the skills and information from which you can make informed decisions, and carry out those dives having fully planned them if you so choose. Whether or not you wish to carry out such dives is of course a personal decision, even so the skills you learn will add an extra layer of knowledge to your regular diving. It's a very worthwhile course, and is complemented by PADI DM - while they overlap in some areas they have other areas which aren't covered by the other (I'm BSAC DL which is 3 Star and part way through my DM)

- BSAC says it's OK for divers to do single tank deco dives, so all of the other organization that say otherwise should be ignored.

No. BSAC TEACH Planned Decompression as part of their recreational curriculum - the reason's why and how have been covered before.

The other agencies choose to teach Deco as a "tec course" because their rec courses aren't of sufficient length to tech the skills and knowledge required

 

[Storker]

Whether or not you wish to carry out such dives is of course a personal decision, even so the skills you learn will add an extra layer of knowledge to your regular diving.

Exactly.

 

[Edward3c]

...
(I'm BSAC DL which is 3 Star and part way through my DM)
...

I'm interested to know where you got this information from. As BSAC is not a member of CMAS therefore there is no star rating of our qualifications. However, Advanced Diver used to be 3 star, both Sports Diver and Dive Leader were 2 star.

 

[Lorenzoid]

Can you not see the risk difference between a dive involving 10 minutes air deco and one with an hour of 50% and oxygen?

And is that more or less risky than an NDL 40m dive in nasty vis with old net or fishing line on a wreck with big holes to accidentally swim into?

Good point. I would say that whether it's 10 minutes of air deco in nice conditions or a NDL 40m dive in dangerous conditions, both dives need training and equipment beyond what is taught by PADI et al. Stopping to hold depth for some amount of time dictated by a planning tool doesn't merit some special "deco bogeyman" risk category that sets it apart from other risks.

 

[Centrals]

I do not recall ever taught planned deco dive is part of recreational diving(PADI standard).
If I want a 10 min deco dive I will use twin set with proper deco mix. Period. If others believe or trained otherwise it is their choice/training.
I have never came across any operator in our part of the world that will let you do a planned deco dive on a recreational dive.