Normoxic Trimix in Mod 1???

Gill Envy

I'm starting to feel just willfully ignorant about He and having a chance to experience it early on may have helped me get over the jitters. Tri-mix has haunted me for many years. Maybe it's that one thing that I keep resisting to help stay in denial that I am tec diving. Under current mod1 certification perameters, it seems that it's arguably dangerous to stay close to the max depth for any length of time without the benefits of the "lite gas".

Mixing the words recreational and trimix might just be a good thing. It's a bit tricky though as diving conditions are so radically different around the world. Mod 1, in cold water adds a lot of factors. Cold water requires a dry suite, a dry suite and a rebreather pose a significantly increased risk of uncontrolled ascent. I have accepted the fact that I will never be as nimble on a rebreather as I was on OC. I agree that Bouency control must be mastered before adding a greater consequence to uncontrolled ascent but I don't know enough about He to know where that line should be drawn.

That said it seems that there is a big gap between mod1 and mod2 for those of us that get into rebreathers without previous technical training. You could use that to argue that taking longer to get into trimix would be better or you could say that starting out with a little He in the mix early on is particularly valuable for those who have no experience to go on and may have irrational misconceptions about it. I'd like something in between mod1 and 2 to be more prepared to deal with longer periods at the deeper end of the certification, but I also think that throwing the opportunity of experiencing a little He into mod 1 would help the likes of me get past the mind block of "The Demon Gas". If I find it's the "paper tiger" that some are saying, i'll be frustrated I didn't figure that out a lot sooner.

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Gill Envy

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jkaterenchuk

I hope someone will take the lead.

After my Mod 1 and slowly increasing depth I finally got to the 30 m plus range and did not at all like the high level of anxiety I was feeling in cold and low viz conditions. So I did some research, talked to some experienced people and decided to introduce low levels of He into my diving. Luckily I can blend my own so I have not needed the card. My feeling after doing this is that I am very glad I did not have a failure on one of the 30m plus dives prior to using He. I would have been less likely to have dealt with it in a logical systematic manner. Hence, I agree with your position 100%.

John

Brainx3

Hi guys,


I agree on the concept of "Can't drive a machine under influence then why would dive a machine under influence?"

CCR diving requires more attention to our equipment while diving than OC as we need to always monitor O2 and deal with problems in case they happened so therefore our level of awareness should be higher than just diving on OC. I think any negative factors that would interfere in keeping good focus would be better to be eliminated in the first place.

So how about voting to make changes to MOD 1 in order to introduce Helium to CCR divers?


Best Regards. Wael

hillbilly

Joe,

Thanks for the correction on the TRD.

Couldn't you do the TSD theory/practical and TTR combined. I had a look again at ANDI's site and it shows TTR (Prereq as TSD). Not really keen on diving air as a dil to 50m for the TRD course. I don't have an issue with the TSD, but they should have it available as a CCR course.

Dsix36

Regarding the use of trimix and the effects of narcosis in my training.
My instructor told me "If your are never narked, then I did my job right".

IMHO - CCR's and narcosis is an incident waiting to happen. Being clear headed on a Rebreather is vital.

I don't have a trimix card, but no captain, divemaster etc. has ever asked for it. They don't know or care what gas I have. I have only been asked for my Optima card once in over 50 dives.

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jradomski

TTR is not listed TTM is.. TTM requires TSD, TTR requires TRD (which requires TSD or equivalent).. 50M is the MAX depth.. There is nothing that says you have to go that deep.. The class can easily be accomplished in 30m-40m depth.. Its about skills not depth...

For those WITHOUT TSD they do a combined class with TRD all on the CCR.. No need for OC.. The suggested dive progression (8 dives) really works well..

For someone with OC trimix the TRD class can be done on TMX as long as all team mebers can use the same dils and bailout gases..

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Joe Radomski
CCR Trimix Instructor Trainer
ANDI Instructor Trainer Director #10

All posts are personal opinions and DO NOT reflect any affiliated agency unless specifically stated.

Brainx3

Hi,


Well, the thing is with Tech diving is that courses seem to be integrateable on almost any level. But the point is redefining the boundries of the existing courses in order to extend the safety factors. The thing that I find is that there are lots of Tech instructors worldwide and I have met the good and the bad ones in my experiences. With limited experience instructors they might not want to tell you that you can be more safe with some helium in the mix because simply is doesn't say so in the standards. So in general, increasing awareness and safety levels in CCR is essential but since almost all know that then why not changing the standards to implement the positiveness of introducing Helium from MOD 1?


Best Regards. Wael

EBT

...or they may be managing their liability in an increasingly litigious society.

Given that folks on a mod 1 arent going deep, theres only hassle in using helium with students if you dont need to. The best way to understand what makes sense is to see what they dive when they're not teaching. Its usually a trimix dil... and before people rush to bleat about evil instructors, remember that we're all part of this society.

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Brainx3

Hi,


True, BUT, giving an advice to your students to increase their safety factor isn't a negative thing especially on the last dives on MOD 1 which would become deeper than 30 meters and would have narcosis effects. AND, if the standards of MOD 1 changed then the insurance would cover the diver since he/she would be diving within their training limitations.


Best Regards. Wael

PhilSiswick

I think giving 'advice' to your students is dodgy, especially as moving to mix would theoretically allow them to dive deeper and therefore make them more likely to incur the negative impacts of using He.

Combining Mod 1 with a suitable mix qualification, or extending the standards to include mix, is the right way to go. No argument.

Cheers,

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Phil

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