Next step for longer bottom times on deep dives?

[Gareth J]

Accelerated Decompression is listed under Club Diving, not Technical Training.

Edward.

My main point was the core DTP includes staged decompression. If you complete Sports Diver, you are qualified to do staged decompression, no additional courses are required.

ADP is an SDC (Skill Development Course). It is an additional course to the DTP (Diver Training Program).
It is also still managed by the Tech' Group, entry requirements include the Black Buoyancy entry qualification. In addition, you, as an instructor you need an additional endorsement to teach the course.

Something like O2 administrator can be taken as an SDC, but it is included in the DTP at dive leader level. Any OWI instructor can teach the O2 course, either as part of the DTP, or as a stand alone SDC.

In short, if a Sports Diver rocks up on a boat, he/she is qualified to complete staged decompression dives. He/she needs no further courses or qualifications.

For those not aware of how the BSAC is structures.
The main diving qualifications are all elements of the core DTP, Diver Training Program. Each diving qualification, Ocean Diver, Sports Diver, Dive Leader, Advanced Diver is part of the DTP. (The one exception is First Class, which is managed and run separately.)
The BSAC has a series of other courses, complementary to the DTP. These are called SDC's (Skill Development Courses). They may have specific entry requirements and may require specialist instructors. They are divided into three (four) specific groups. Rescue, Seamanship, and Diving. Diving is spilt into two, general, and technical. Technical diving is supervised by the Technical Diver Training Group.

As an example, the O2 SDC can be taught by any BSAC NQI (Nationally Qualified Instructor). You can attend it with no diving qualifications. All the elements of the SDC are taught as part of Dive Leader. If you complete the DL course, you have completed the O2 SDC, if you complete the SDC, you no longer need to complete those specific elements of the DL course.
(In my branch every other year we teach the O2 SDC, it is heavily encouraged that all branch members attend the course, irrespective of diving qualifications. For those learning to dive, we know they will know how to diagnose diving related injuries and administer O2. For those already qualified, it is a refresher.

A further example is Diver Coxswain SDC, this is an assessment rather than a course. It takes a day. It requires specialist examiners. It is not required for any DTP diving qualification. If you hold the Diver Coxswain award you can apply for the International Certificate for Operators of Pleasure Craft (ICC).

Gareth

 

[kensuf]

As I mentioned upthread, NAUI has separate certs....

Technical EANx Diver
Decompression Techniques Diver

Not anymore. It's now Technical Decompression Diver and one combined cert.

 

[Scuba Client]

Okay, let's summarize.

OP wants to extend bottom time and go into relatively short deco times. Typically will occasionally dive around 90 to 100 feet, depths where gas density isn't an issue. If the OP goes deeper, the OP understands that there is increased risk of gas narcosis inhibiting responding properly/quickly to emergencies. That is a risk the OP must make for themselves.

Gas density has been discussed (and dismissed entirely by some) as a risk factor which has to be considered against one's own personal risk assessment, cost, and availability/convenience.

As the OP is not a prolific diver to these depths, a rebreather isn't financially viable/practical.

CCRs are for logistics.

 

[Scuba Client]

I can’t speak for Dr. Mitchell as I don’t know the man personally but I have a number of friends who are scientists in different fields. Prior to publishing their work or results of studies, they consult other scientists to examine the data And conduct a mini peer review prior to publishing. Now as I said I don’t know if Dr. Mitchell does the same. But I’d be willing to bet money that he doesn’t operate in a vacuum.

When you say community do you mean us divers? Because if you do I would take the knowledge and recommendation of a single individual that studies decompression science over thousands of non-scientists.

Now people can accuse me of name dropping, but it isn’t that. It is citing a credible source. An expert source that overrides one’s hubris of knowing better than anyone else based upon whatever.

You haven't been keeping up with medical journals involving scuba, otherwise you would know Simon Mitchell is an Assistant Professor.

 

[Scuba Client]

Helium and therefore an empty wallet (as helium has become insanely expense) is in your future. If you are going to dive deep prolifically, consider closed circuit. But prior to that, get the fundamentals down. I advocate GUE fundies or similar before starting tech.

I personally wouldn't do a GUE Fundamentals course but would recommend a Decompression Procedures/Advanced Nitrox course before stepping up to CCRs. Provided you can breathe deep air. Whatever that means...

 

[Scuba Client]

Exactly.

I did tech training for precisely that reason - to spend more time on wrecks in the 90-130 foot range. Narcosis susceptibility is variable, of course, but if you are doing dives in that range now and just want more time, no need for trimix.

I did my OC tech training with John Chatterton, and if you like wrecks, this is a great option - you will hear a lot of awesome stories and get good teaching. But of course, there are a lot of options for basic AN/DP. I did TDI, so I don't know much about the PADI offerings.

One of my mentors is a PADI techncial instructor, and he weighs up the pros and cons of different training agencies. Most of the theory is the same.

 

[Scuba Client]

If we asked Dr. Simon Mitchell if it is his professional recommendation that all recreational training agencies limit all recreational diving to 100' or below due to the gas density and/or narcosis safety concerns/risk in the current 101-130' recreational range until divers are trained on and using trimix to make the dive safe? I'd be very, very surprised to hear him say that should be done as a blanket "rule" for diving. I know he doesn't endorse "deep air diving", but I don't know that he 'opposes" diving on air/nitrox at 101' for instance. It seems to be that some people are saying that's his position however, so I'd love to get clarification on his professional thoughts for that scenario.

I could be wrong, and I'd love to hear his answer, so maybe @Dr Simon Mitchell will answer that question.

Assistant Professor Mitchell has stated using 32% as a decompression gas is fine.

 

[grantctobin]

Assistant Professor Mitchell has stated using 32% as a decompression gas is fine.

Sure. Do you know at what point in diving you begin to use 32% or 30/30 as a decompression gas? In your view, what is the difference between the two? At what depth do you switch to 32%?

 

[Scuba Client]

You can have a look at these reports, but they're a bit old:
http://media.dan.org/RF3_web.pdf
http://www.swiss-cave-diving.ch/PDF-dateien/2008TechDiverReport.pdf

Wikipedia has a lot of references here:
Rebreather - Wikipedia
Scuba diving fatalities - Wikipedia

There was a report about diving safety citing three categories of divers at high risk:
(1) newbies (<100 dives of experience)
(2) people who dive often (>300 dives per year)
(3) rebreather divers
Unfortunately, I do not manage to find this report anymore... so take my information with caution

All these reports are relatively old, so things may have changed now; the idea I got is that 10 to 20 years ago they were less safe because they were less known. Now I believe things are changing - but it's just an impression, nothing more.

The real discussion lies in respiratory issues with old people who partake in technical/recreational dives. Young energetic, vigorous individuals shouldn't concern themselves when breathing dry air.

 

[Scuba Client]

Sure. Do you know at what point in diving you begin to use 32% or 30/30 as a decompression gas? In your view, what is the difference between the two? At what depth do you switch to 32%?

Thank you for your question. I've had the privilege to meet some very experienced divers. Their opinions vary and I accept both for the very reason, if you wish to dive with them, they propose the gases. Example: 32% switch at 40 metres PO2 1.6. The other example: 30/30 at either PO2 1.1 or whatever the software generated dive plan allows. Plus whatever the last/next decompression gas was or is. Isobaric Counter Diffusion theories are extrapolated and debatable. Sometimes, you just can't demand the gas you want. So if my software generated dive plan has no spike in the Equivalent Air Depth, and looks reliable, I propose it to my buddy.