trimix training

[waterpirate]

1. I see value in deep air training as part of a trimix class

2. I do not see any value in deep air training as part of a trimix class

3. I have no opinion.


So I was roaming around the internet the other day, bored, and came acrossed a website advert for normoxic trimix training. The description of the course is what got me thinking. It stated that after skills and drills they would be doing several deep air dives in the 180fsw range prior to conducting the trimix dives. The description went on to say that there were valuble lessons to be learned on these deep air dives.

I found this to be very curious. I do not dive deep air. People do. What was the lesson to be learned? I do not see the value in deep air as part of a mix class. Your threshhold for narcosis should have been addressed in a much earlier class, or during adv/nitrox-deco proc. what say you?

Eric

 

[mathauck0814]

I think it's worth doing two dives on the same site - one with mix and the other without. Not sure it needs to be 180fsw, but if it's a divers' first trimix course (some agencies are offering hyperoxic trimix courses) they likely have had the narcosis problem demonstrated but not solved in the way that this exercise would demonstrate.

 

[Adobo]

Is this a poll? If so, I think I am having a brain fart as I cannot find where to enter my vote.

Anyway, I have never taken a class where deep air was part of the curriculum so its not clear to me what they do as part of those dives. If their process is to dive some nitrox mix to 30m/100ft and then while there, have the student breath trimix, then I understand. It presumably gives the student an opportunity to do an A-B comparison.

However, the way I have heard this in the past is that some agencies want to "get a diver ready" for trimix dives by introducing deep air. I don't understand this approach. It seems like saying, we will make it unnecessarily hard before we make easy.

On a side note, the other thing that makes me scratch my head is that several agencies will train a diver to dive 2 deco gases before they introduce trimix. Given a choice, I would rather have trimix and one deco gas as opposed to diving deep on nitrox and then having 2 deco gases.

 

[skankpile]

At least you will know how you will do on deep air if you need to or can't get He at location. It will be fun regardless.. go for it.

 

[rivers]

I wouldn't take a trimix course that required me to do a deep air dive. I know what it feels like to be narced at 100ft. I can only imagine what it would feel like at 180ft. I don't need to experience it.

 

[nimoh]

how are you expected to learn lessons at 180FSW on air when you can't remember them?

 

[RAD Diver]

When I was looking at doing the deeper classes 1 agency had you do extended range (deep air) before Trimix but then after doing extended range & getting into trimix the 1st thing they tell you is never dive deep on air. So why is extended range a prerequisite to trimix in their agency?

 

[Dr. Lecter]

Given the possibility of having to use air in an OOG emergency, I have a hard time seeing how anyone would want to do a basic trimix course without first having dove air at those depths. For more advanced trimix classes, it probably has little to no relevance since as you get into the deeper 200' range, certainly past 240' or so, the risk of tox makes air far less relevant. As for the idea that you can't remember what you learned/did at 180' on air...

I wouldn't take a trimix course that required me to do a deep air dive. I know what it feels like to be narced at 100ft. I can only imagine what it would feel like at 180ft. I don't need to experience it.

Much like EtOH, everyone responds to narcosis differently... but you should at least consider working up to it, as you (a) might be surprised at how functional you are, and (b) may one day find yourself going to 180'+ on air for an emergency and that's not the time to wonder whether it's as horrible as you've been told.

 

[waterpirate]

I think it's worth doing two dives on the same site - one with mix and the other without. Not sure it needs to be 180fsw, but if it's a divers' first trimix course (some agencies are offering hyperoxic trimix courses) they likely have had the narcosis problem demonstrated but not solved in the way that this exercise would demonstrate.

I agree with this, but it appears that the AN/deco is now being offered with heliox, or trimix light if you will. That is where I see those 2 dives on different mixes being done around the 100-130 range with a complex problem of some sort being the indicator. Some people do well, others not.

---------- Post added July 19th, 2013 at 12:22 PM ----------

At least you will know how you will do on deep air if you need to or can't get He at location. It will be fun regardless.. go for it.

That may be a valid statement. I think the world is devided now into those who do deep air and those who do not. Those who do not do deep air seem to choose to skip the dive if the mix is not available. I know that I do.
Eric

 

[nimoh]

Given the possibility of having to use air in an OOG emergency, I have a hard time seeing how anyone would want to do a basic trimix course without first having dove air at those depths. For more advanced trimix classes, it probably has little to no relevance since as you get into the deeper 200' range, certainly past 240' or so, the risk of tox makes air far less relevant. As for the idea that you can't remember what you learned/did at 180' on air...



Much like EtOH, everyone responds to narcosis differently... but you should at least consider working up to it, as you (a) might be surprised at how functional you are, and (b) may one day find yourself going to 180'+ on air for an emergency and that's not the time to wonder whether it's as horrible as you've been told.

Why would I have the possibility of having to use air in an OOG emergency? On a 180' dive, the choices based on what me and my teammates are carrying would be 21/35, EAN50 and O2, and I have no intentions of finding out what the latter two are like at 180'