TDI TRIMIX DIVER and deep air

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

I think some people are forgetting the original question.
The wording is a bit inclear, would that include/cover a dive without helium below 45m? Or would such a dive necessarily require the extended range certification because there's no helium?
Some of the earliest responses asked the critical question--who is doing the requiring? A dive operator running a dive? A dive insurance company?

The simple answer is the same for each--it depends upon the dive operator or insurance policy.
 
Frankly, TDI has internally tried to nix it more than once and a very small group of vocal instructors have thrown a “we can’t get helium and deep air is fine” fit.
So you are saying that the training agency and its QA, Scientific Board, and BOD has allowed a course they deem inappropriate in the current era to remain because a “small” group of instructors insists it’s safe? That’s a pretty damning statement for the training agency.

The more likely reason it remains in my mind is that folks are diving deep air anyway, and they won’t stop anytime soon with the current helium prices…so maybe a course where they can be exposed to that level of narcosis under supervision is the right thing to do.
 
So you are saying that the training agency and its QA, Scientific Board, and BOD has allowed a course they deem inappropriate in the current era to remain because a “small” group of instructors insists it’s safe? That’s a pretty damning statement for the training agency.

The more likely reason it remains in my mind is that folks are diving deep air anyway, and they won’t stop anytime soon with the current helium prices…so maybe a course where they can be exposed to that level of narcosis under supervision is the right thing to do.
But the purpose of the course is to allow you dive without supervision. Does that justify the course?
 
But the purpose of the course is to allow you dive without supervision. Does that justify the course?
That the purpose of all courses. Expose students to new things, then certify them when they have demonstrated competency in those thing iaw X agencies standards.
 
That the purpose of all courses. Expose students to new things, then certify them when they have demonstrated competency in those thing iaw X agencies standards.
My point was not clear, obviously. You said maybe the ER course was OK because you were narced under supervision. I don't see that justifies the course, since the point of the training is for you to dive without that supervision.
The idiocy is that the ER instructor is NOT required to be on He, and may have up to 4 students; so we have the possibility of a narced instructor trying to manage four narced students. It really begins to sound like NOT a good idea.
 
You said maybe the ER course was OK because you were narced under supervision.
Maybe I was unclear. What I meant to imply is that if people are going to dive deep air anyway, why not have a course that not only exposes them to it under supervision of someone that already has that tshirt, and teach them to manage narcosis? It’s a good opportunity to mentor divers and let them see for themselves that narcosis is highly variable with different conditions, while providing them the insight as to why it may not be the best way to go about things.

You are right that the instructor doesn’t have to be on helium…which could be problematic if shite hits the fan.

The point is that folks dive on air to 55m all the time. It’s not ideal, and we know that…but neither is not offering a training opportunity for people that are going to do it anyway.
 
teach them to manage narcosis
How does that work? Is that not just a hopeful myth, like getting acclimated to high PPO2?
 
How does that work? Is that not just a hopeful myth, like getting acclimated to high PPO2?
Not really a myth, it’s more about being able to recognize when you are impaired, and adjusting your depth/dive plan before you are high as a kite and unable to make sound decisions.

Some folks can function relatively normally at 180’ on air…《mod edit》others can't handle it and aare as if quite drunk《mod edit》. I think it may be more personal physiology than it is acclimation.

What is certain is that everyone has some level of impairment at that depth on air (reaction time, cognition, perception).
 
https://www.shearwater.com/products/perdix-ai/

Back
Top Bottom