IANTD Deep & Advanced Nitrox - Oxtox?

[Melicertes]

Congratulation....
If you Interesting deep water dive...go for IANTD Advanced Nitrox/Deep diver twin tanks setting ...
Not necessary to buy a big single tank

Please pardon my ignorance but advanced nitrox is AFAIK generally considered dives on 40% - 50% nitrox. To keep ppO2 under 1.4atm a dive with 50% nitrox leaves me with a maximum depth of about 57.4ft (17.5m) to avoid increased risk of oxygen toxicity. How is advanced nitrox practically combined with deep dives on the IANTD Deep/Adv Nitrox courses? It just seems almost like a contradiction in terms to me. I'm not wanting to stir the can of worms here, just truly interested as I am looking at the courses myself for the future.

 

[TheRedHead]

Rich mixes of nitrox are carried in a slung bottle and used for acclerated deco. They aren't used for your primary or "back gas." 100% O2 is often used the same way. I don't know if IANTD certifies for 100%, but my TDI class did.

 

[Cave Diver]

Please pardon my ignorance but advanced nitrox is AFAIK generally considered dives on 40% - 50% nitrox. To keep ppO2 under 1.4atm a dive with 50% nitrox leaves me with a maximum depth of about 57.4ft (17.5m) to avoid increased risk of oxygen toxicity. How is advanced nitrox practically combined with deep dives on the IANTD Deep/Adv Nitrox courses? It just seems almost like a contradiction in terms to me. I'm not wanting to stir the can of worms here, just truly interested as I am looking at the courses myself for the future.

From the IANTD website: http://www.iantd.com/iantd3.html

Deep Diver
This program has been developed to provide responsible training to divers who plan to dive to 130 fsw (39 msw) on air. The IANTD Deep Air Diver program trains divers in skills, performance, theory and planning of deep dives. This program remains within the commonly practiced depth of 130 fsw (39 msw). It is the first sanctioned program to provide proper international training in safe deep diving skills and performance. It is recommended that this program be taught in conjunction with the IANTD EANx Diver program.

Advanced Nitrox Diver
This program is designed to extend the divers knowledge with O2 mixes of 22 to 40% and up to 50% for decompression. It further develops diving skills and provides a greater understanding of the Nitrox diving concept.

 

[cloudboy55]

Advanced Nitrox typically deals with blends of between 40% and 100% O2 for the purposes of accelerated decompression. The gas is carried in one or more deco bottles and are breathed during decompression only at depths above the danger zone for oxygen toxicity. TheRedhead is right - your back gas will generally be either air or a trimix blend.

 

[DA Aquamaster]

I took deco procedures and advanced nitrox through TDI, but the theory is the same.

You do the deep portion of the dive on air or some other suitable nitrox mix where the max PPO2 is at or below 1.4. The higher precentage deco mixes are used for the deco portions of the dive with a max PPO2 of 1.6.

A higher PPO2 is used durng deco to obtain more efficient offgassing and is considered acceptable because the deco portion of the dive is a fairly low workload portion of the dive.

Normally, you will switch to 50% at the 70 ft deco stop where the PPO2 will be 1.56 and stay on it until you reach the 20 ft stop where you will switch to 100% with a PPO2 of 1.6.

Obviously, switching to the wrong gas at depth can be fatal and much of the course is devoted to the procedures required to ensure you identify and switch to the right gas at the right time. Switching to the incorrect gas is consistenly the biggest single killer of tech divers, so it's perhaps the single most important skill you can learn.

 

[TheRedHead]

From the IANTD website: http://www.iantd.com/iantd3.html

Those courses are rec courses whereas TDI's Advanced Nitrox is taken with Deco Procedures and are tech courses certifying you to dive to 150 feet. I assume you would do simulated deco in this course?

 

[PerroneFord]

Those courses are rec courses whereas TDI's Advanced Nitrox is taken with Deco Procedures and are tech courses certifying you to dive to 150 feet. I assume you would do simulated deco in this course?

IANTD Adv. Nitrox is *not* a recreational course. I took that course. Nothing recreational about it!

 

[Rick Inman]

I just finished IANTD's Adv Nitrox and Advanced Recreational Trimix. The quote in Cave Diver's post, and the info in DA Aquamaster's post says it all.

Although good classes on their own, it seems to me that the Deep Diver, Adv Nitrox & Adv Rec Trimix classes are really just transitional classes leading into, and preparing the diver for full Trimix.

JMHO

 

[TheRedHead]

IANTD Adv. Nitrox is *not* a recreational course. I took that course. Nothing recreational about it!

On the IANTD website, it is listed under "Non Technical Diving." That's why I said it was confusing.

 

[Rick Inman]

On the IANTD website, it is listed under "Non Technical Diving." That's why I said it was confusing.

Like I said. It's transitional. Here's my class report.