Reason for Rec Triox?

[MHK]

It depends on the person, the day, the conditions, the depth, the task, etc. I think it nuts to dive mix to 120 with eighty degree plus water, two hundred foot of visibility and a look/see dive plan. But move that dive to 40 degree water, ten foot of visibility and a very complex dive that requires clear thinking and team work to accomplish … well, then I take the best mix I can get. Where’s the line in between? I don’t really know, that’s a judgment call. I don’t get very narked, I usually dive NITROX on air tables for a little extra margin (at least down to 130).

The one other point we like to emphasize is that while for sure we worry about narcosis in that depth range, we also are concerned with gas density issues and the added ability to retain C02, which is dramatically more narcotic then N2. I hope what the overwhelming majority of my students take away from the Rec Triox class is the all to often dives in the recreational range are done with very little attention to detail. If you go to most any artificial wreck you will see way too many divers penetrating solo, with single tanks, on air with little in the way of gas reserve, other then "be back on the boat with 500 psi" You will be shocked when you see the expression on the face of most of my students when we actually calculate how much gas is needed to reserve for 2 divers OOA from 100'.. Most haven't considered the point..

 

[Rick Inman]

Subjective answer:

I do dives up to 130' on HE-free gas, but I enjoy a 120'+ dive a lot more with the HE in the mix. In our cold, dark waters (yesterday's dive was 36 degrees with 4' of dark vis), I feel the difference at 100'+ with the HE and enjoy the dive more.

I first started noticing it when I would top off my doubles with 40% after an 18/45 dive, and end up with something like 26/30, and do a dive in the 100' to 130' range. I didn't really notice the nark factor so much, just that I seemed to enjoy the dive more. And that is why I dive. For fun.

Hey, it's my money and my gas. What's wrong with a little squirt of HE to make the dive more enjoyable if I want? I know it's more macho to dive deep without it, but I gave that up when I hit forty.

It always surprises me that some people are so adamantly opposed to people diving HE who haven't "paid the training price" or something. I know HE reserves are low again, but I wouldn't worry about GUE's rec Triox class effecting that too much.

Sounds like a good class to me.

.02

 

[KMD]

We are not talking shallow are we? I thought this was 100+ we where talking not a 30' to 80' cave or wreck.

The Yukon in San Diego starts around 80' and bottoms out around 100'. If you were doing a penitration of the ship, wouldnt you want a little HE in the mix just to be able to think that much clearer?

RecTriox is just another tool in the bag that can make your dives and dive planning safer and more enjoyable.

 

[Dive-aholic]

Okay, lots of great information here! Thanks to all who have posted constructive comments!

Without meaning to come across as critical, what I'm coming out of this with is that maybe Rec Triox isn't the best name for this course. Sure, it includes the use of trimix, but as has been said a few times, that's a small part of the course. So why not call it something else that better describes what it's about?

MHK, or anyone else, I still don't understand the point of using trimix to those depths if you're not going to incur a deco obligation. Yes, I've done shallow backgas only cave dives in which I haven't had a deco obligation. But I'm also not going deeper than 60'+. So no need for He. And if you're going deeper with a task in mind, then isn't it likely you'll be incurring a deco obligation? I also teach rock bottom calcs, but I teach it in OW, so my students aren't as shocked because they don't know any better. They're more shocked when I tell them about the 500psi rule.

Rick, I see your point. The reason I dove trimix on a dive with a max depth of 98' was because I had it left over in my tanks from a previous dive. But on that dive I didn't feel as clear minded and I'm not sure why. The money comment is just from the books. I'll pay for it when I feel I need it. Diving 100' on air isn't a macho thing either. Actually, it was my wife's suggestion. She typically feels the effects of narcosis before I do and has even called dives because of the narcosis. This even happened on a dive to the 150' range on 21/30. She wanted to try to build up her tolerance to the narcosis so we could do that dive with her feeling a little more clear headed and suggested we try 100' dives on air instead of 100%. We ran the profiles and saw there was minimal difference in deco. So we started doing it. She's built up the tolerance and we'll be doing that dive again when we return to N. Florida. Will we ever dive deeper than 100' on air? Can't say. Maybe, maybe not. Again, it's not a macho thing. It's working up to the dives we want to do. Eventually we'll be doing dives to the 300' range. We can lower our air content only so much, so the answer, for us anyway, was to build up the air tolerance.

 

[Divin'Papaw]

Okay, lots of great information here! Thanks to all who have posted constructive comments!

Without meaning to come across as critical, what I'm coming out of this with is that maybe Rec Triox isn't the best name for this course. Sure, it includes the use of trimix, but as has been said a few times, that's a small part of the course. So why not call it something else that better describes what it's about?

I think they have changed the name. I was just looking at the latest GUE standards last night (2006 date). I believe it's called Recreational Diver 2 now, not Recreational Triox.

 

[Dive-aholic]

On their website it's still Rec Triox: http://www.gue.com/Training/Recreational/triox.html

 

[ppo2_diver]

It's still called Rec Triox.

As MHK pointed out, a big reason for helium in the mix is to reduce CO2 retention. If you are doing your cave diving at 60' with no deco, you could be fighting a strong flow, you can become task loaded, etc. Helium reduces the CO2 retention caused from breathing heavy.

 

[TSandM]

I honestly don't know the answer to whether helium is worth it at 100 feet or not, but my Fundies instructor told us a very frightening story about narcosis. He had done a dive to 100 feet on air (helium unavailable) and had to manage a minor issue at that depth and was unable to complete a simple task he had done hundreds of times (and we're talking about somebody for whom emergency procedures are something he can do in his sleep). He aborted the dive, and on the way up at a stop, rechecked the problem and discovered what he had done wrong. The message was a powerful one: A man with extensive and intense training was unable to do something simple at depth AND WAS UNAWARE THAT NARCOSIS WAS THE PROBLEM. If that's the case, what about somebody like me, who is narced at 100 feet and knows it?

I hate to say that money is no issue, but I can afford to put helium in my tanks if I want to. And if it clears my head at 100 feet (which is a depth I don't do all that often, anyway) and increases my safety by doing so, it's worth it to me.

90 percent of this class will be managing issues at depth, anyway. It's going to be three days of air-sharing ascents, maskless ascents, and midwater SMB deployments. It's going to be situational awareness and functioning as a team and crisp, unambiguous underwater communication. It's a tech diving class without doing decompression, is what it is

 

[mrjimboalaska]

While diving >20 dives a month, adding He to the mix can get rather expensive. At the moment, I dont even pay for air, but am now going to start diving Nitrox exclusively, just for an added safety margin. Since most of my dives are ~100ft in 75-81' temps, I just don't see the need of He.
Now, when doing the deeper stuff, which isn't every dive, I'd like to use He, thus Trimix class is on the list of things to do, but I also get tired of "drill diving", if all I do is drills on every dive, hell, I'll go back to my single HP100 and dive for fun...oh wait, I do that already.
Since every dive is a decompression dive, it cracks me up to hear people talk about no deco obligations, unless doing an Emergency ascent, deco should be standard practice.....3-5 minute "safety stop" anyone?
He, if you want and can afford it, why not use it........but I feel it is not needed at the 100ft. level.....but opinions are like.....

 

[Adobo]

Without meaning to come across as critical, what I'm coming out of this with is that maybe Rec Triox isn't the best name for this course. Sure, it includes the use of trimix, but as has been said a few times, that's a small part of the course. So why not call it something else that better describes what it's about?

How about "Doing it right - Advanced Open Water"?

MHK, or anyone else, I still don't understand the point of using trimix to those depths if you're not going to incur a deco obligation.

KMD gave two examples that I thought were pretty compelling.

I also teach rock bottom calcs, but I teach it in OW, so my students aren't as shocked because they don't know any better. They're more shocked when I tell them about the 500psi rule.

From reading Scubaboard, it's clear that it's not taught in most Open Water or even AOW courses. There is at least one agency that offers this level of gas planning (and beyond) no matter who the instructor is.