More than "Advanced", but not really "Technical"

[DevonDiver]

There is no such thing as "FAKE" deco. You set your computer to the parameters it is meant to be set by; accounting for DCS pre-disposing factors etc.

Why play trickery with the instrument that is safeguarding you? K.I.S.S.

At the end of the day, your physiology versus the dive profile dictates DCS. No button pressing on a computer changes anything about that. No chicanery will get you longer in the water... if you are diving prudently (and that includes setting your computer realistically based on the physiology, conditions and activity).

Why fuddle you computer to force a slower ascent? Set your computer properly and add whatever sensible stops you feel are beneficial to increase your conservatism and insulate against DCS risk. I do a 9min ascent from 9m, with 3 stops, for my recreational dives. I don't need to engage in tomfoolery with my computer to do that. I'd be a moron if I needed to... because it'd mean I couldn't trust myself to simply remember a simple amount of ascent profile...

 

[Scubadude_LA]

I dive a DG03, and while it's not perfect, I think that the price point and overall divability is good. So, I'll throw that in the mix. The only thing it does that REALLY drives me crazy is it starts yelling at you when your ppO2 goes over 1.2. You can get it to shut up by pushing a button, but it's still stupid that I have to. However, it'll follow you beyond your ppO2 limit and even let you switch to O2 deeper than 20ft, but it'll fuss at you and make you acknowledge that you're doing bad.

Off Topic, but you can customize the PO2 alarm setpoints in the computer's configuration menus.

Humbly back on topic,

Man just rent some doubles and go take AN/DP if you like diving and want to progress a bit. You will be diving which you like, and you will understand once your done why it's 130 no deco or deco with redundant bottom gas, with proper planning for contingencies for lost deco and bottom gas and oops, I stayed too long or 10 feet deeper.

Folks here are giving great advice because most of them know what they thought before training and what they think now after doing a training dive and the instructor pointed to them leaving the bottom and said by the way, you just lost your deco gas and you left 160' 6 minutes late. You will have hand calculated gas planning, and cut hand tables (using deco software or tables) which will give you new perspective on those few extra minutes you are trying to squeeze out of a single tank. You will do this using whatever fancy rec/tec computer you have on your wrist in BT mode for good reason and will be running hand cut tables, which will also be an eye opener. Later in life you will own a real tec computer with the rec/tec in BT with backup tables if the tec computer fails. All sounds old school and boring and unnecessary until you go through it and understand the exponential things that go on for each extra minute/foot. Even if you never dive these profiles again you will be a much better diver for it anyway.

You would without question gain enough to make it worth it even if all you ever do is rec.

I like training, think about it, you are basically doing "personal" pinnacle dives when your in class, you have a mentor challenging and watching over you and if you divide the cost of the class by the # of dives you make in the class it is probably the same cost as cattle boat charters per dive.


Just go do it and my post will be here for you to come back and thank me when your done, seriously, this is all good You will like it and doubles.

 

[gcarter]

Deleted

 

[geoff w]

Ignoring incompetence on the part of recreational divers going into a decompression obligation, it can happen to capable divers due to either situation or location. A couple of years ago in Fiji, our group was at Rainbow Reef. At one end of the reef, the current picked up to the point where our group (which included a few card carrying tech divers) couldn't hold on to the reef and got swept off. Being between some deep pinnacles, there was also a strong down current. I grabbed my wife and the two of us bounced deep before we could regain buoyancy and start ascending. At this point, our computers (Suunto) were in deco mode. The real incompetence was on the part of the dive operator putting us in the water when they did. The experience scared the crap out of me and made me start thinking about taking deco procedures training, not to intentionally incur a deco obligation, and not so I could be less aware of remaining NDL time, but for when environmental circumstances do something like this

The other reason I'm interested in deco procedures training is because some friends that sailed around the world are planning to go off cruising to the south Pacific again, and we're planning on joining them in a few locales. They're purely recreational divers, but in a few locations went on recreational deco dives, most notably the Coolidge in Vanuatu. Not knowing any better, and believing the dive shops, the happily followed the deco profile provided by the dive shop. While this is all well and good, blindly following a "recreational" deco plan from an out of the way south Pacific dive operator kind of scares me, and makes me want to be better armed with knowledge to validate their deco plan. My friends said it was single tank diving, but there are tanks dropped at the deco stops, along with saturated paperback books to read while waiting to ascend

Based on both the scenarios I described, I think both fall within the original competent-single-tank-diver-going-into-deco description. I personally have no plans to become a tech diver, going beyond recreational limits, nor diving with more than a single tank. But I certainly see the value of taking deco procedures training for just the scenarios I described.

If anyone is interested, Allan Power Dive Tours, Vanuatu is one diver operator's description of their Coolidge dives, catering to all levels, and talking about how divers spend their time completing decompression. It sounds like wonderful recreational diving

 

[Dive-aholic]

What some of you are not getting though is that single cylinder decompression diving is against the safety standards that have been developed for overhead diving. There is not sufficient redundancy in a single cylinder to plan a decompression dive, no matter how "recreational" you want to believe it is. Recreational agencies have procedures in place should you exceed no decompression limits. Rather than even worry about these you should be planning your dive and diving your plan. Planning "recreational" decompression dives is not acceptable. And if a down draft takes you deeper than planned, in this case you were not planning a decompression dive and you should revert to what you should have been taught in your recreational OW class.

 

[uncfnp]

Reading through the thread I can't find anyone that has once suggested advanced diving with out redundancy. I think part of the problem is that there are some recreational divers that want additional training, that want to know more and be better divers. That would like to explore the beginnings of decompression theory to better dive recreational profiles. And these divers will never advance to full tech dives and may even feel physically unable to schlep a full tech kit not to mention the cost. Is it unreasonable for an instructor to tailor a tech class to met the needs of his student while insuring that the student gets the complete education and dive experience required by the course?

 

[Scubadude_LA]

Reading through the thread I can't find anyone that has once suggested advanced diving with out redundancy. I think part of the problem is that there are some recreational divers that want additional training, that want to know more and be better divers. That would like to explore the beginnings of decompression theory to better dive recreational profiles. And these divers will never advance to full tech dives and may even feel physically unable to schlep a full tech kit not to mention the cost. Is it unreasonable for an instructor to tailor a tech class to met the needs of his student while insuring that the student gets the complete education and dive experience required by the course?

IMHO: SDI Solo would be great here since gas planning is a huge part of deco. Redundancy would be introduced and other self help skills that a tech dive would need to progress if ever.
As far as theory, the books do a good job if you never practice it, but if you practice it you need the tech gear. Once you pass the point of CESA/NDL you are an overhead diver and I wouldn't want even 10minutes of missed deco which is all this single tank stuff would ever get you anyway, if that. I'd have to run the numbers, but even if you carried a high o2 deco what you would have to keep in reserve backgas incase of lost deco would negate any extra time you thought you had.
I would think that is where the fine line is regarding training.
Just my two cents, I think

 

[uncfnp]

IMHO: SDI Solo would be great here since gas planning is a huge part of deco. Redundancy would be introduced and other self help skills that a tech dive would need to progress if ever.

Been there, done that. Now I want more.

As far as theory, the books do a good job if you never practice it, but if you practice it you need the tech gear. Once you pass the point of CESA/NDL you are an overhead diver and I wouldn't want even 10minutes of missed deco which is all this single tank stuff would ever get you anyway, if that. I'd have to run the numbers, but even if you carried a high o2 deco what you would have to keep in reserve backgas incase of lost deco would negate any extra time you thought you had.
Just my two cents, I think

Again, no one suggested at any point that the course should not include redundancy. Just maybe not in the form of doubles.

 

[Scubadude_LA]

Been there, done that. Now I want more.


Again, no one suggested at any point that the course should not include redundancy. Just maybe not in the form of doubles.

Hence, Solo which requires a redundant gas supply and gas planning for it. I use an AL19 slung and treat like an NDL dive when solo/rec. AN/DP is not aggressive tech diving, it's the next logical step.
My view from taking those courses was that the progression has been pretty well thought out by
the training industry (or at least the ones I used).
I don't really see an spot in the middle after being put in the scenarios and running the numbers.

If you want formal training next stop (no pun intended) is AN/DP/Introtec level training and doubles.
Frankly, your not gonna get much more without doubles or a rebreather, unless you just want to know the theory.
Not trying to be bullish, but I really believe this, I've gone through the progression and from my perspective can see clearly where the line is.

Anyway, you can take DP and AN in single tank H-valve config with 50% deco if I remember correctly.

 

[Dive-aholic]

Reading through the thread I can't find anyone that has once suggested advanced diving with out redundancy. I think part of the problem is that there are some recreational divers that want additional training, that want to know more and be better divers. That would like to explore the beginnings of decompression theory to better dive recreational profiles. And these divers will never advance to full tech dives and may even feel physically unable to schlep a full tech kit not to mention the cost. Is it unreasonable for an instructor to tailor a tech class to met the needs of his student while insuring that the student gets the complete education and dive experience required by the course?

It's been suggested several times that decompression dives should be allowed in a single cylinder recreational kit. That is without redundancy. Anyone can audit a class. I would have no problem with a student who wants to sit through my classroom portion and even do the first day of dives where we don't go deeper than 60' and only do simulated decompression. However, I will never bring a student with a single cylinder to 150'. So no certification would be issued.