Deep Air Diving - thoughts

[Hank49]

To use "not paying for trimix" as your excuse for deep air diving is the same white trash type thinking as not paying for one of those "fancy house things" in order to justify living in a trailer ..

I....uh...ah....never mind....

 

[JeffG]

To those new to tech diving and looking at deep air diving and trimix, do your research and read scientific studies and listen to experienced divers anecdotal evidence and then make up your mind. Don't just trust what you read on the internet. Also, there are several agencies available to teach you technical diving. Read their standards, compare their track records in the real world and above all else, use your own common sense.

There is the true crime of Deep Air. Not so much as diver's using it (as Thalassamania has said 000's of deep air dives have been completed successfully), but that training agencies teach it before trimix. That gives an impression that it is "easier" than helium.

I believe that all technical divers should be taught to use Helium first (and a couple of agencies agree with me) and if the diver chooses to use Air, then at least he is making the decision from a position of knowledge. He/she would then be able to balance the cost/benefit vs risk/reward for themselves.

A "Deep Air" (read non-helium) trained diver cannot do that. They are missing 1/2 of the data to make a reasonable choice.

The agencies have given their stamp of approval on this type of diving. Thats the crime.

 

[peterbj7]

The agencies have given their stamp of approval on this type of diving. Thats the crime.

It's always possible that they do know what they're doing, that they have enormous combined experience, have conducted lots of research, and have come up with that conclusion. Oh, but I forget - they can't know what they're doing because they came up with the wrong answer.

A bit like those poor misguided fools in Europe who keep voting No to total integration as one country. Never mind - keep throwing it back at them and eventually they'll get it right.

 

[peterbj7]

Upon reviewing the video, I saw a log laying parallel to the mooring line and about 4' away. I never saw that log on any of the dives. It was about 18" in diameter and rather hard to miss in the video. I don't think I forgot about it, I never saw it. I was narced and fixated on the mooring line.

Another possibility is that you were totally focussed on the job in hand and how little time you had to perform it, and you simply excluded from your consciousness anything that was at the time irrelevant to the task.

 

[JeffG]

It's always possible that they do know what they're doing, that they have enormous combined experience, have conducted lots of research, and have come up with that conclusion.

LOL..Did you actually think that?

It came about because of no research and fear of helium. And stayed because of the "Been there...done that" attitude of the true dive stud.

Oh, but I forget - they can't know what they're doing because they came up with the wrong answer.

You are right for once.

 

[JeffG]

Another possibility is that you were totally focussed on the job in hand and how little time you had to perform it, and you simply excluded from your consciousness anything that was at the time irrelevant to the task.

spin spin


LOL

 

[24940]

Another possibility is that you were totally focussed on the job in hand and how little time you had to perform it, and you simply excluded from your consciousness anything that was at the time irrelevant to the task.

Well, the task at hand was to free a mooring line, not free the mooring line so it could snag on a log I failed to notice. I got lucky and that didn't happen, but when focus turns to fixation, it comes at the expense of situational awareness.

Accomplishing tasks under the influence of narcosis requires great focus on the task, but fixation is a real danger.

 

[MXGratefulDiver]

I've made 100s of dives between 150 and 190 and (as far as I can remember) I've never forgotten anything about the dives.

I envy you ... my memory's not that good on the surface ...

... Bob (Grateful Diver)

 

[peterbj7]

It came about because of no research and fear of helium. And stayed because of the "Been there...done that" attitude of the true dive stud

I bow to your superior knowledge and experience.

 

[Thalassamania]

Another possibility is that you were totally focussed on the job in hand and how little time you had to perform it, and you simply excluded from your consciousness anything that was at the time irrelevant to the task.

Perceptual narrowing and the concomitant loss of situational awareness is what tends to be the problem.

I envy you ... my memory's not that good on the surface ...

... Bob (Grateful Diver)

After careful thought, please permit me to amend that slightly. To the best of my current recollection I never came up from a dive having "forgotten" what happened on the dive. There have been dives (at all sorts of depths) that I have forgotten to do something, or done something incorrectly (I have several notebooks full of my "personal incident reports"). I applogize if I gave the wrong impression, perhaps my memory's not that good on the surface either ...

I remember a project where we had to locate and then drop down 180 feet and tie a line onto a 6 ft clump of concrete that housed an oceanographic instrument (at a designed tie-on spot). It took four dives (other divers) doing circle sweeps to find it and mark it. I swam down hard (40 degree water and about 10 feet of vis). When I got to the bottom I started to tie the line on and noticed underneath me a goosefish that was about the size of the clump. This made me nervous and broke my concentration, but, leaning over the goosefish I tied a knot and then surfaced. When we tried to winch the clump up the knot gave way and we would have to reattach. I could have sworn I tied a good bowline, but I guess with the goosefish and the narc I was mistaken. After and hour SI I went back down, this time with a big clip tied to the line. I guess goosefish like to get out of the current, because he was back in the lee of the clump. I approached from upstream, cliped in and the job was done. Moral of the story ... simplify the task as much as you can and don't depend on properly carrying through with any detailed task. Frankly that's a good lesson even for a 10 foot dive.