PADI Deep Diver course- gas management

[Leatherboot69]

I had an enjoyable Sunday morning reading this thread from start to finish. It seems - in sum - that agencies (including PADI) have published training standards that are research backed and that allow recreational divers to dive within certain risk tolerances, but that some commenters on the thread do not think that those standards are correct based on several reasons ranging from conjecture and opinion to anecdotal experience to interpretation of subsequent research.

I was taught gas planning at OW, AOW and Deep Spec levels. I’ve found I’ve had relatively limited need until recently to use the calculations for single tank NDL air dives in the <30m range rather than just knowing my turn pressure and reserve, which of course is how millions of dives each year are safely conducted. The main reason I’ve started using them is to prevent skill fade rather than because they have been intrinsically useful on a dive. I would definitely use them for dives in the 30-40m range where risk tolerances are lower because of the increased gas consumption and shorter NDL times, as well as having less experience at those depths and so less instinctive understanding upon which to base decision making.

I’m actually quite confident in PADI standards for NDL recreational diving in circumstances similar to in which I’ve been trained or in which I have developed experience - which is, of course, all I am certified for. There is no incentive whatsoever for PADI to publish training standards or other material that is unsafe.

 

[wetb4igetinthewater]

Well that settles it!

 

[Kris Reynolds]

I teach the PADI Deep Diver course fairly often in Canada. It think it is worth while for many students, especially if they are considering going beyond the course into any more advanced diving.

For many of the students that I teach, it is the first time they have actually use SAC to plan needed gas consumption in advance of a dive. The planning process (which many have long stopped practicing) makes it clear that small things can snowball quickly. Many divers tend to become complacent over the years following Advanced Open Water, and the deep course increases caution and diligence. It also proves to divers that narcosis does in fact affect them, regardless of how they might perceive that it doesn't.

The course is a good indicator for divers that they may or may not be ready or might not actually want to continue to the Tec program.

Lastly, more advanced diving; technical diving in particular has a considerable barrier of ego surrounding it. It can be intimidating, and uninviting for divers who don't have peers already diving to those levels. It can be hard to find a team to progress with. A course like the PADI deep diver course allows them to continue progressing safely with an instructor, and often meet others who want to continue to with them.

Courses of any kind offer more opportunities to keep divers engaged in the sport, and can often expose divers to instructors that may expand and improve upon what they have learned, and that's mostly a good thing.

 

[Capt Jim Wyatt]

Plan and manage gas use, including determining turn pressure, ascent pressure and reserve pressure. Establish no stop and dive time limits.

Gas management. Before beginning the descent, remind divers to check their starting pressure and make a note of their turn pressure. During the dive, check cylinder pressures at irregular intervals to confirm appropriate gas management.

Those sentences were copied/pasted directly from the PADI Deep Diver Instructor guide.

 

[jadairiii]

Plan and manage gas use, including determining turn pressure, ascent pressure and reserve pressure. Establish no stop and dive time limits.

Gas management. Before beginning the descent, remind divers to check their starting pressure and make a note of their turn pressure. During the dive, check cylinder pressures at irregular intervals to confirm appropriate gas management.

Those sentences were copied/pasted directly from the PADI Deep Diver Instructor guide.

Does instructor guide define what "appropriate gas management" is? Is "reserve pressure", the individual diver's reserve or the team's reserve? Or is it, "go to 90', come back up and have 500psi in your tank when you are on the boat"?

That was sort of the question of my original post. But this was helpful, thanks.

 

[tursiops]

Does instructor guide define what "appropriate gas management" is? Is "reserve pressure", the individual diver's reserve or the team's reserve? Or is it, "go to 90', come back up and have 500psi in your tank when you are on the boat"?

I suspect you already have an opinion on what is "appropriate gas management."
So what answer to your question could be given that you would not argue with?

 

[Leatherboot69]

Delete

 

[Capt Jim Wyatt]

Does instructor guide define what "appropriate gas management" is?

Negative.

 

[jadairiii]

I suspect you already have an opinion on what is "appropriate gas management."
So what answer to your question could be given that you would not argue with?

I do have an "opinion" but that was not the purpose of my original question (read my first post). And I had followed up that I did not want to "argue" the point, merely learn what is being taught, per PADI standards. My last PADI class was in 1982, AI, just wanted to know what is current teaching.

Capt Jim answered it, PADI does not define what "appropriate gas management" is, in the Deep Diver course.

 

[tursiops]

I do have an "opinion" but that was not the purpose of my original question (read my first post). And I had followed up that I did not want to "argue" the point, merely learn what is being taught, per PADI standards. My last PADI class was in 1982, AI, just wanted to know what is current teaching.

Capt Jim answered it, PADI does not define what "appropriate gas management" is, in the Deep Diver course.

Capt Jim did not quote all the relevant parts of the Instructor Manual for Deep Diver.

Appropriate gas management is talked about multiple times in the class. For example, one of the performance objectives of Deep Dive One -- which, by the way, is also the Deep Dive for AOW -- is this:

Plan and manage gas use, including determining turn pressure, ascent pressure and reserve pressure. Establish no stop and dive time limits.​

In the briefing for Deep Dive One, it is suggested to:

5. Have buddy teams plan their turn pressure, ascent pressure and reserve pressure for the dive based on gas supply limits.​

6. Have buddy teams establish maximum depths and bottom times, and plan and plan contingency profiles for longer and deeper dives than planned.​

A performance standard for Deep Dive One is specifically about gas management:

a. Before beginning the descent, remind divers to check their starting pressure and make a note of their turn pressure.​

b. During the dive, check cylinder pressures at irregular intervals to confirm appropriate gas management.​

Deep Dives 2-3-4 have similar statements.
Other parts of he IM and the Deep Diver Student Manual discuss gas consumption rates, and how to determine if you have enough gas for the dive.