TRIOX ?

[Freedive WI]

1.6 p02// ??? :-X WHO would run a bottom P02 of 1.6 in cold water?? ??? I hope that tewch divers would know better.


We never go over 1.4 for a bottom mix, and that's to the MUD not just ideal max depth. 1.6 is only used for deco gases and air breaks may be included to keep you to away from the "knife's edge" of toxicity.

We do a lot of survey dives on, and IN, shipwrecks in the 120'-130' range. Using triox helps you keep your data straight in your wet notes. It also helps with camera controls.

I am not going to get into some chest beating discussion about how "good" we may or may not be on deep air. In the past I dove deep air, as well as many others on here I am sure. But the fact is there are safer ways to do things and I have have evolved my diving technique with the times.

Triox doesn't cost that much more if you mix it yourslef. The problem comes in with some greedy shops that want to charge a ton of money for something simple. You can even mix triox with your nitrox "premix" that's already banked in the shop. Add a little HE, add a little nitrox, top with a bit of air and check your mix. Pull out your palm pilot to run your tables, I bought mine for $75 at Circut City, and your off.

I understand that this may seem like a lot for some diveshops at this point, but remember that nitrox was a HUGE deal for diveshops 10 years ago. Give it time and it will come.

I don't know why some shops won't accept GUE cards? It is more of a turf war or some kind of an ego threat than anything else. IF someone want's to come and dive with a rebreather or DIR go ahead. Your all adults and can choose for yourself. If you've got the card then someone out there is willing to take responsibilty for your training.

As far as the added expense of argon, most Great Lakes wreck divers that I know have been using argon for years, even if the still dive "air". It makes a big difference and you can build a set up in your garage in less than an hour. I strongly encourage any drysuit diver to use it no matter what you breath. 8) We acutally have an argon hose tied into our icediving lines that we train new ice divers with. HTe argon tank stays at the surface in a heated ice shanty and the end of the hose has a splitter with two suit hoses coming off of it. Not only are you Y-clipped to your buddy, but your also suit clipped. It makes a big difference to have heated argon being pumped into your suit when your suit when your in the "hole" for a good six hours or so running students through. 8)

Another point on limits. We regularly do 90 minute dives on the wrecks in 135' with close to 60 minute bottom times. The club policy is that you can dive that deep on nitrox, but you can only make a 30 minute, bottom time, dive and NO penetration. If you go over 30 minutes of bottom time, or enter an overhead enviroment, then you need to switch to triox for that dive. We have no 02 issues with the conservative nature inwhich we plan things out.

You can still dive air of course, I am just giving you a glimpse of what the future will bring. IF your shops are raking you over the coals for trimix fills it might be time to travle somewhere else and learn how to do it yourself. Thereis a lot of hype and misinfromation out there about gas mixing and it really isn't that hard to do. PADI even has trimix blending certifications out now and their trimix program is suppossed to be out this summer.

Jon

[cdtgray]

My mention of exposure limits as an issue was only there as something to be considered.
My primary reason for not using triox is simply that of cost. I'd love to mix my own gas, but that simply is not a possibility for me. So given that I'm at the mercy of LDS mix prices, the benefits of using mix for depths under 130 just don't match the costs.

[DRE]

I know SD&T will accept the GUE card and will fill triox mixes if you want (check with them for prices). As far as cost is concerned - yes it will be more, but what's your life worth? Especially in overhead environments I want to be as clearheaded as possible - most fatal accidents have happened in the 100-150 range with people diivng air or nitrox - narcosis does play a role.

[cdtgray]

most fatal accidents have happened in the 100-150 range with people diivng air or nitrox - narcosis does play a role.

Without providing aditional information as to what happened on those dives where fatalities occured, to to state that the effects of narcosis were to blame (in part or in whole) seems to be an overgeneralization. For instance, were the divers cave trained, did they have appropriate equipment, did they have appropriate quantities of gas for the dive, and/or was something such as a heart attack to blame?

[Freedive WI]

Let me give you some real specifics.

We have a wreck in the Milwaukee area in 95' of water. It is a great place to freedive and the vis can be up to 85'. She has claimed at least 4 divers that I know of. Some were trapped inside and couldn't find there way backout. Most people would say that since it's so shallow you don't need to worry about narcosis, remember it's shallow enough that I snorkel it, but once you get inside of something it blows your mind by how much more detail you remember if your on helium. I dove that wreck for 20 years onair and nitrox before diving it on helium. The first triox dive I did on it I saw more little details that I ahd never remebered seeing before.

If your not ready for triox, that's fine. It will take a while for it to get to the masses, just like nitrox did. But, please don't discount it's value without ever trying it. It wasn't that long ago that nitrox was considered the "devil's gas" and now everyone seems to be using it.

BTW: exposure limits are based upon 02, as in nitrox, and not upon the helium content. IF your pushing things so far that your goingto have an 02 issue, it's certainly not becasue your diving helium.

Jon

[DRE]

The accidents I was referring to involved cave certified divers who were carrying all of the necessary equipment, were not diving beyond their skill level (such as scooter diving 3000ft back in a cave when only intro certified), but who still didn't make it out alive.
Data collected by the IUCRR () until 1999 showed that of a total of 37 cave certified fatalities 13 died in the 100-200 ft range (6 in the 100-150 range), and the highest cause of cave diving deaths is related to depth (13 out of 40 cases).
I'm not saying you can't do a dive on air to 130ft safely (although added HE and O2 are more beneficial from a deco perspective) in OW, but the added task loading of being in an overhead environment can easily lead to fatal outcomes when sh*t hits the fan. Triox does fill the gap between nitrox and trimix and is a much safer mix to dive.

[LKunze]

That's why I really find triox interesting and can see it being a great benefit for diving wrecks in Superior. I did two dives on the Madeira last summer for the first time and I got a little narced on the deep part of the wreck at about 100ft. Unfortunately I don't remember a lot of the details of the dive because of that. Also I don't really buy the argument of building up a tolerance to narcosis. I've done a number of dives to the 100ft range on air and nitrox and I'd say that half of my dives I felt narced on and half of them I didn't.

[tbrown]

So let me see if I got this right. A Triox fill will cost more (but doesn't everything now days). It gives the advatage of Nitrox ie. extended bottom times. And gives the advantages of HE, less narcosis. It has the same downsides as Nitrox, such as MOD ect. I had read about GUE offering the class, but the article I read was more about the class and less about what the gas would do for you. How does SAC compare? I understand that when breathing an HE based gas, your SAC goes up (something about density). Is this a myth or is there some truth as well.

[Elph]

[quote author=Freedive WI

If I dive a 28/30 mix I don't need any other deco bottles, although I sometimes carry them to get out of the water even faster. The only extra gear that you MUST have is an argon bottle for your drysuit since you can't inflate a drysuit with trimix because you'd freeze.

I understand that diving with argon makes you warmer than filling your dry suit with plain air (or in this case triox), but I don't know why. I would've assumed it's because it's a noble gas, but helium is as well and that's what you're using in triox.

[Inspirationdiver]

Argon is a much denser gas than helium, nitrogen, or oxygen. It is a much better insulater than these also, in other words, it conducts heat slower. By using argon to inflate your drysuit the warmth from your body will be conducted more slowly into the surrounding water. Helium is much less dense than air and therefore conducts heat more rapidly. Air is a pretty good insulator but argon is much better than air or helium.