View Full Version : Trimix at Rec Level

06-21-2012, 15:55
I have notice at least one agency has a rec level trimix coarse and rumor that several others will be following with rec coarse of their own (except Padi). Below is the Prerequisites:

"Must be a qualified Advanced Open Water Diver or equivalent and EANx Diver or take the EANx Diver course in conjunction with the Recreational Trimix Diver course.
Must provide proof of a minimum of 15 logged dives.
Must be a minimum of 15 years of age with a parent or guardian authorization, or a minimum of 18 years of age without guardian approval. "

That gives you no deco and if you a AOW if only gives you 100 feet max depth. The next level of training gives you 160 Feet and upto 15 minutes of Deco. What this does is eliminates all those deep air dives build skills and levels to get to Trimix. I was talk to one person that seemed to know what being tossed around by some agency and claims that Nitrox/Trimix may not even require a dive in the near future. It was brought up that as average age of divers increase, divers putting on extra pounds, and the fitness of divers get worse this helps eliminate the accidents on deep air. Your thoughts?

06-21-2012, 17:35
Introducing light helium mixes along with eanx early in a divers training I feel is a slippery slope. Reducing the N2 load and subsequently the narcosis on any diver is a good thing but that has to be tempered with caution. Just because you are now clear headed enough to do the deeper/longer dives, doesn't mean you have the skills to pull it off. It's not the advanced mix that will cause the problem, it's the required decompression that will bite them in the a$$ once they go past their training. At 15 dives, I would guess that most new divers are unable to ascend slow enough or have the buoyancy skills to hold the stops. Dangerous, even on 100ft dives where you blow past the NDLs. Helium is still an inert gas being absorbed. Bent on He or bent on N2, still bent...

To your point Dennis, I agree completely, deep air dives are tough, hard to think, hard to breathe but are useful in building skills and ingraining that it is dangerous down deep. Things that go oopsy at 60ft, can seriously screw up your day in the 150-200ft level. Giving the inexperienced the ability to hit those marks I feel would be reckless with the qualifications listed.

06-23-2012, 10:17
I think what ever some is breathing doesn't make more or less likely to break the rules, some people sees rules as hard fast limits and others just loose guide line. I also don't think someone should go from OW and 60 feet to AOW and 100 feet without spend sometime developing skill learned in OW. I do believe that 15 dives most divers don't have the skills to safe ascend and hold safety stop. One agency wants you to 3 levels of deep air before going to Trimix and I think that is excessive, you should do a couple of deep air dives for the experience. Another agency has "Advance Rec Trimix" that requires 30 dives (I think more like 100 dives) or satisfy the instructor that you have the skills. When I talk to a instructor he said 1 or 2 dives would be over 100 feet and on air and at least two dives on trimix. You still have a ton of limits on mixes, max depth of 160, and no more than 15 minutes of deco. That sounds like the best plan to me!

06-26-2012, 10:14
Narcosis really isn't a major issue shallower than 100', so Nitrox is the gas of choice for me. Once you cross that line, Trimix comes into play - especially in the overhead - but like Aquatrax said, you immediately begin racking up decompression obligations, which I think are clearly beyond the scope of recreational diving standards.

Recreational nitrox and technical or advanced nitrox are two different beasts entirely. And it's my opinion that trimix diving should require a considerable amount of training and experience beyond those. None of them are the answer to unsafe physical fitness or diver attitudes, and I suspect that accidents on deep air are rarely the result of having an extra pound or two of age on the diver.

But enough talk of trimix, training and trip review are overdo!

07-21-2012, 16:45
I think this is crazy. As a both nitrox and advanced nitrox certified diver, there is no way that I would have been ready after just a few dies to throw in trimix. I feel ready for my upcoming deco class and then ready for trimix. This just seems like another quick way for the dive agencies to make some quick cash from divers who just want to say they are trimix certified without being truly taught the ins and outs of diving.

07-22-2012, 15:17
While the prerequisites seem liberal, they say nothing about what the course is all about or what the criteria is for passing the class. AFIAIK the rec trimix course that IANTD offers is for recreational depths only and there are no deco dives.

Program Limits
No dives may be conducted to depths greater of 130 fsw (39 msw) and no END greater than 80 fsw (24 msw).
Appropriate safety decompression stops must be performed. (Safety stops will be at 30 fsw (9 msw) - 20 fsw (6 msw) and 15 fsw (4.5 msw) each stop will be a minimum of 1 minute).
No dives having a mandatory decompression Stop may be made (unless the course is combined with one requiring stops)
No dives made me made with a PO2 greater than 1.6.

The Skills for the course and dive theory seem more than adequate.

Nitrox review
Role of Stress in Training, Physics and Gases, Breathing Mixtures, Dive planning, Reducing Risk, Carbon Dioxide and Helium, Trimix no decompression diving, Oxygen toxicity: cns and otu, Gas calculations: deeper into FO2, PO2, Gas consumption and planning, Diver physiology and helium, Advanced buoyancy control, Surface Marker buoys and up lines, Gas sharing emergencies

To pass the course you must be able to pass the written exam, plan and execute the dives. If you can do this by the end of the course I don't really care how many dives you had when you entered the course. IMO, the key is what the diver can do consistently after the course!

I have yet to see a single IANTD instructor who is really interested in just handing out c-cards, most are glad to take your money and make you earn the card, but that's just limited to my experience it may be very different elsewhere.