What people think of SCUBA training

[Charles2]

There were many brands of double hose regulators that were of single stage design. I always understood that the single stage designs varied considerably in breathing effort from full tank to empty. My 2 stage double hose (if you can make it out in my avatar) got a little hard to breathe when the tank pressure got low - that was how we knew to pull the J-valve and end the dive. I am not aware of any single-hose regulators that are of single-stage design.

 

[Eric Sedletzky]

If you have ever seen a ScubaPro Mk 2, you have seen an unbalanced 1st stage.

I could be wrong, but I think any 1st stage that attaches to the tank valve on its end (versus on the side, like any higher end reg) is an unbalanced 1st stage. That design does not have anywhere for a balance chamber to live.

Besides, the Mk 2, other examples would be the Hollis HO2 O2 reg, and the various DGX and Dive Rite drysuit inflation 1st stages and O2 deco regs.



I was really surprised during my IDC by one of my co-instructor candidates. He is a friend that is also a technical diver. during a classroom session during our IDC, it became clear that he didn't really understand how regs worked - e.g. 1st stage drops pressure to 140-ish, 2nd drops it to ambient. Difference between a piston and diaphragm. Difference between balanced and unbalanced. Him being a techincal diver also, I was pretty surprised at his lack of detailed knowledge in that area.

But, it begs the question, does a recreational diver really need to know those things?

A question I like to ask, to see how people respond is "if the 2nd stage is dropping a higher pressure down to ambient, why do we need the 1st stage? Why can't the 2nd stage just be the only stage, and drop the pressure from 3000 (or whatever) all the way to ambient in one stage?" So far, nobody has ever had a ready answer.

Conshelfs attach on the end.

 

[Magnus Lundstedt]

I could be wrong, but I think any 1st stage that attaches to the tank valve on its end (versus on the side, like any higher end reg) is an unbalanced 1st stage. That design does not have anywhere for a balance chamber to live.

I have some Aqualung (US divers) Conshelf XIV and SE2, they are balance and have the attatchment in the end.

 

[60plus]

Have you ever dove a single stage regulator?

No, but welding with single stage regs has made me aware of hir shortcomings.
See single stage regulator delivery pressure | The Harris Products Group in welding this is called the rising pressure characteristic of a single stage regulator.

 

[BDinSH]

It is common for people who never dived to have no notion about Scuba training, so I don't see anything strange about the question OP mentioned by his customer - I am getting asked these days if you can learn scuba if you cannot swim!
I think there is another length discussion on "Change in Scuba Industry". The change is the market, and industry has to change to meet the market. Change has pro's and con's, but is eventually measured by survival. I see the agencies had been changing their standards and methods and I now consider mostly for the good of the industry.
The answer to OP's customer in the original post is YES and called Discover Scuba. Not a certification level but does "train" a person to experience scuba. When I first come across DSD I thought it is a very bad idea; I have since changed my view that with proper "training“ and good judgement by the instructor it can be done safely and effectively. It suits the change of market and served it well - many would not have gone on to OW had they not tried DSD first. There are still many go straight for OW if they KNOW they want it.

 

[BDinSH]

There are two discover scubas with different standards--pool only and open water. Going out on the reef is perfectly fine, assuming all proper standards were followed. It is part of the incentive that made me a diver as well.

I believe there is only one standard just who can conduct what portion of the class (confined vs open).

 

[TMHeimer]

It is common for people who never dived to have no notion about Scuba training, so I don't see anything strange about the question OP mentioned by his customer - I am getting asked these days if you can learn scuba if you cannot swim!
I think there is another length discussion on "Change in Scuba Industry". The change is the market, and industry has to change to meet the market. Change has pro's and con's, but is eventually measured by survival. I see the agencies had been changing their standards and methods and I now consider mostly for the good of the industry.
The answer to OP's customer in the original post is YES and called Discover Scuba. Not a certification level but does "train" a person to experience scuba. When I first come across DSD I thought it is a very bad idea; I have since changed my view that with proper "training“ and good judgement by the instructor it can be done safely and effectively. It suits the change of market and served it well - many would not have gone on to OW had they not tried DSD first. There are still many go straight for OW if they KNOW they want it.

I agree with your last two sentences. Problem with DSD is (IMO) that the instructor (or DM) to student ratios are apparently violated more than you would think--so I've been told by those with first hand experience. The standards themselves (again IMO) of more that a 1:1 ratio invite trouble.
An old discussion on SB for sure.

 

[BDinSH]

Use PADI as an example, I believe DM course covers everything that an Instructor has to cover. In terms of skill and knowledge of diving, DM are supposed to have learned as much as what requires for an Instructor. What one retains afterwards of course is another issue. DMs, even those assisting OW/AOW courses usually do not participate in classroom/theory portion, so over time they maybe more likely to remember that portion from the course.
IDC/Instructor course emphasizes on "how to teach" - presentation and student coaching (and how to sell PADI). DM can be certified by an Instructor; only course director can teach Instructor course and IE are administered by PADI directly. I would say Instructor qualification are more "uniform & consistent" but not more demanding.
Theory part of course had been toned down significantly; it still covers all the topics (except computer replaces dive tables) but much less emphasized. Students are made aware of these yet there is an acceptance that it is not practical to expect them to spend the effort to be so knowledgeable and retain those knowledge long after the "test". Time is better spend in the water. Knowing DIN vs Yoke, balance vs unbalance, how first stage & second stage work makes knowledgeable diver but not necessary better divers, especially in new divers. More emphasis on get the student into water early; while kneeing on bottom is still often practiced on initial pool session, it is encouraged to get to neutral asap and do as much skill learning neutrally off the bottom.
The fact is market change, target potential customer change and part of the industry is trying hard to meet it. I may not agree with everything that changes all the time, but I applaud the effort. I believe in the last 5 years certification number worldwide has actually increased.

 

[TMHeimer]

I agree with PADI's move to lessen theory and add practicality in the DM course (I have yet not been offered $500 to retrieve a 100 pound outboard motor from 100 fsw). I do believe that when a DM takes the IDC there is some of that "missing" theory which must be covered to become an instructor. Others may have more knowledge on this.

 

[BDinSH]

I agree with PADI's move to lessen theory and add practicality in the DM course (I have yet not been offered $500 to retrieve a 100 pound outboard motor from 100 fsw). I do believe that when a DM takes the IDC there is some of that "missing" theory which must be covered to become an instructor. Others may have more knowledge on this.

I recently went through just that after a conversation with someone about DM course vs Instructor course (actually there is no Instructor course, just IDC). Comparing the two, Instructor course does not contain any more skill or theory/knowledge than DM, but IE is more comprehensive, requires a higher passing score and administered stringently (no wifi, book closed, no paper notes, cell phone off etc. Think of it as a graduation exam.) DM's get signed off progressively at the pace of their choice by Instructor; often there is no dedicated DM instructor so a combination of different instructors on various portion of the course.

IDC is geared towards review of information and get ready for the exam. The extra portion for Instructor is that it grades you on how well one "teach" (present the information) and candidate must pass that as well. DM has to pass the same skill set proficiency with demo but not graded for skill teaching (i.e. student error detection and correction)