Deco for Dummies?

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Mike, as far as I know, no standard agency teaches anything regarding emergency decompression to recreational divers beyond the "8 minutes at 15 feet" idea.

UTD Rec 3 teaches the use of helium mixes for the deeper (100 - 130 feet) recreational range, and discusses how to manage a small amount of mandatory deco.

I believe GUE Rec Triox teaches some information about backgas deco as well.

It is very reasonable, in my view, to teach recreational divers who want to spend more time in the deeper ranges, something about how to determine a reasonable amount of decompression and where it should be done. But along with the intellectual material comes the education on how diving changes, once you have incurred a decompression obligation, and the training to solve problems and deal with issues underwater, since once you are in deco, you can't just surface if something goes wrong. Also, you have to have a sense for calculating gas requirements and safe reserves. Just knowing how many minutes of deco are required and where they need to be done is the very smallest piece of being prepared to handle a decompression obligation.
 
In answer to the original question BSAC, SAA and some other European agencies include decompression diving from their second level "Sport Diver" (CMAS2 Star) and include deco with a second gas (up to 50%) in their Advanced Nitrox Courses.
However if you feel the need to go decompression I would recommend doing aa course with a good technical instructor (even if you don't want to be a "Techie")
 
In terms of skills, decompression is not an especially demanding skill. Hang at appropriate depth for appropriate time and be sure to ascend especially slowly.

Courses on planned decompression diving are much more focused on the planning (especially the gas planning) than the physical decompression stops themselves.

Most recreational divers, by definition, will be doing unplanned decompression (if you want to do planned decompression, take an appropriate course), so it is just a case of hanging below your ceiling for the relevant time (or if that is not possible, for as long as you can).

The theory of decompression is interesting to some but excruciatingly dull for others. For me, it's +1 on Mark Powell's Deco for Divers. Much better than any agency manual I ever read.
 
To Everybody:

I just ordered Mark Powell's Deco for Divers from Amazon.com ($36.87)

As always, you guys and gals are great. I love it here.... but my wife Katy is gonna kill me if I don't get off the computer now.

Mike
 
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I think you will love the book. Despite some editing mishaps, it is, in my opinion, by far and away the best discussion of decompression theory for the average diver that is out there (and I own and have read a lot of stuff).

The more you learn about decompression theory, the more you will realize that there are no bright lines -- risk is a progressive thing that increases with the product of depth and time, but is also affected by individual and temporary factors that we don't understand very well at all.

My training, once I got off the "mainline", has been that ALL dives are decompression dives, in the sense that all dives involve ongassing and offgassing, and therefore, all dives should be approached with a strategy that optimizes decompression as best can be done, given what we know. It results in a very different profile from the direct ascent to 15 feet and stay there for 3 minutes that I was originally taught. And thinking that way from the beginning, and developing the skills to execute what we call a "minimum deco" ascent, gives you some insurance against the day when you get delayed at depth and feel as though you should do some additional time in the water. (Of course, along with the decompression information and the skills, I was also trained in maintaining gas reserves to cover such inconveniences!)

And lest anybody think that you can't get delayed at depth, I had my tank slip out of a camband and go totally wonky on me at 100 feet one day . . . and by the time my buddy had it replaced, we were over NDLs. That was also the day that I found out that weighting yourself to be perfectly neutral at 15 feet with an empty BC and suit means you can't put any tension on the line going to the SMB . . . :)
 
I always think accidentally staying over your NDLs is a bit like getting into a car accident.

If you keep d(r)iving long enough, it will happen sooner or later, no matter how careful you are.
 
I am half way through Deco for Divers and it is a very readable book...great information for ANY diver.

To Everybody:

I just ordered Mark Powell's Deco for Divers from Amazon.com ($36.87)

As always, you guys and gals are great. I love it here.... but my wife Katy is gonna kill me if I don't get off the computer now.

Mike
 
It sounds like the question being asked is where I and my son were. While technical diving was a goal the immediate need was information to round out and complete our competency on normal rec dives from a safety standpoint. We went down the path of IANTD Deep Diver then Advanced Nitrox, both of which were good eye openers. Both stress planning which is what we were looking for and gave a solid base to continue. Planning the stops is just a piece of the puzzle. Figuring out the mixes, how much gas, etc. is the true meat and carries over to the casual rec routine. Looking back on our PADI courses and subsequent rec diving it is somewhat scary that we essentially just slapped tanks on and jumped in the water (not implying we didn't think things through/maintain equipment/etc just compared to our now additional knowledge).

Of course going down this path came at a price. From jacket bc's to plates, single tanks to doubles, deco tanks, single regs to multiple reg sets, wetsuits to drysuits, essentially no books to a bunch of books (mental note to pick up a copy of Deco for Divers), redundancy in everything, and the list goes on.....
 
I always think accidentally staying over your NDLs is a bit like getting into a car accident.

If you keep d(r)iving long enough, it will happen sooner or later, no matter how careful you are.

Very true, and in my case these situations often involved getting a stuck boat anchor loose. In fact, my motivation for learning basic decompression technique has mostly to do with being a boat owner. As skipper of a boat with divers on it, you are responsible for much more than just yourself, and I feel that I should be able to respond to various problem scenarios and mishaps. To my knowledge, there is no PADI "Dive Boat Skipper" certificate. But if there were, I would take it.

Then, I could confidently turn to my two friends and say "Bill and Sam, go back down to 80 feet, pry that beam off Veronica's leg, and bring her up slow to 30 feet. Susan, take three spare rigs down to 30 feet and tie them off. When Bill and Sam get there with Veronica, make them all stay for 10 minutes, then come up to 15 feet and do another 15 minutes."

Do I have a Mike Nelson Complex?
 
I always think accidentally staying over your NDLs is a bit like getting into a car accident.

If you keep d(r)iving long enough, it will happen sooner or later, no matter how careful you are.

True...
 
https://www.shearwater.com/products/swift/

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