What's the deal with the "Advanced Nitrox" certification?

[orange_diver]

Maybe I misunderstand due to a lack of knowledge. My understanding is that the point of rec trimix is to do dives in the 100-130 foot range but to have an Equivalent Nitrogen Depth in the 40-80 foot range. So you are deep by sport diving standards but you have a medium depth nitrogen narcosis.



Thanks, I am currently aiming for GUE's Fundamentals course in the Spring. I think that will get me to the same place as your deep class. Sounds like we have the same idea.

sorry, thats what i get for reading too fast. yes you are correct, ENDs of 40-80...

hmmm, in that case, ask yourself what is your purpose? again, you'll be paying a lot more $$ for a fill and NDL limits at 130 are about 5 minutes, so money not well spent IMHO. plus thats pretty deep to be diving single tank.

Fundies are great and if youre going that route better to save ur money for Tech 1, which will encompass rec trimix plus a whole lot more...

 

[wedivebc]

Advanced nitrox is a prerequisite for CCR training.

 

[DA Aquamaster]

I am not a believer in open circuit rec trimix and 30/30 mixes to produce END's in the 40-80 ft range. In my opinion it is a waste of helium.

An END of 100-130 ft I can live with and I have (gasp) done deep air to 150' when the conditions are right and the dive was not demanding. And I have on a few occasions turned the dive as I was not feeling right or comfortable on those particular dives at those particular depths.

But that is a personal bias based on 20 plus years of diving and my particular set of experiences. Different divers will have different levels of tolerance and philosophical differences regarding what is or is not acceptable and will consequently give different answers.

To be honest though if a diver needs an END of 80' or less to feel they are functioning well on the average dive in the 100-130 ft range, technical diving may not be in their best interests and they may want to consider whether they shoudl continue pursuing it.

TDI offers Advanced Nitrox and Deco Procedures which taken together then certifies you to depths of 150' and allows the use of two deco gasses. That made more sense to me than the IANTD 1 gas limit. TDI then lets you expand that with either Extended Range (deep air to 180' - which even I think is pretty stupid) or the much more common Extended Range/Basic Trimix course that is essentially a normoxic trimix course certifying you to 200'. From their you can do the advanced hypoxic trimix course.

Now if you add in a rebreather, recreational trimix and lower sub 100' END's make a lot more sense as the helimum cost and conspicuous consumption/waste factor is about 1/10th what it is on open circuit. And as indicated in a previous post Advanced Nitrox by itself makes sense with a CCR as it shares the same potential issue of high and potentialy prolonged PO2's above the 1.4 max normally encountered in a regular Nitrox course.

 

[texdiveguy]

Advanced nitrox is a prerequisite for CCR training.

It is my understanding that one or more training agencies allow direct entry into CCR training and certf. without ANY prior OC certf. or experience--?

 

[wedivebc]

It is my understanding that one or more training agencies allow direct entry into CCR training and certf. without ANY prior OC certf. or experience--?

I can only speak for the agencies I teach for and both ANDI and TDI require advanced nitrox (CSU) as a prerequisite for CCR.

 

[KOMPRESSOR]

And I can only speak for myself. The most "advanced" diving I do is typical wreck diving (square profile) of depths around 30-40 meters. To get the most out of it I tend to use 28% nitrox in my doubles. Then I carry a 40 stage tank with 50% nitrox. Typical dive would be 30 minutes bottom time on the 28%, and then 18 minutes from 21 meters and up on the 50%. Notice my deco time is from a table with ONLY 28%, so I don't take out the advantage of accellerated deco, but rather use the 50% to make up a better margin for a second dive later the same day. I know trimix is a better gas, but nitrox is easy available and cheap.
My "typical" wreck dive, as described above, is an "Advanced Nitrox" type dive. I've learned from other experienced divers and read myself up on it. And I don't have the certification. I will not advice others to go my way either. So the Adv Nitrox could be a good choice of certification for safer diving with maximum depths of 40 meters if trimix feels out of bounds.

 

[Reg Braithwaite]

An END of 100-130 ft I can live

I have lived with it, I think I have a half dozen dives in that range so far.

To be honest though if a diver needs an END of 80' or less to feel they are functioning well on the average dive in the 100-130 ft range, technical diving may not be in their best interests and they may want to consider whether they shoudl continue pursuing it.

Please be as honest as you like. Your opinion is one data point that is useful for helping me synthesize a strategy, alongside others. I'm sure you are perfectly aware that whether a diver feels he needs it or not, there are also opinions that diving 130 feet on air is to be avoided.

In the end... things like this are just one part of a larger, more comprehensive strategy. Diving with mentors, actual skills training, procedures training, and bookish things like mixed gas training all go together.

My guess is that having the option to dive mixed gas is more useful than having the option to carry richer mixes, especially when that option is useless without choosing to do deco dives. That doesn't mean needing to dive mixed gas, nor does it mean always diving mixed gas, but it's an option.

Thanks for the perspective.

 

[Rhone Man]

Maybe I am missing something, but when I signed up for the TDI Advanced Nitrox class, I assumed it would be about accelerated deco, but I have read the manual cover to cover and all it talks about is the ability using mixes other than EAN32 and EAN36, and you more number crunching on ppO2 and EAD calculations. Although it mentions accelerated deco, it specifically shies away from it (telling you this is covered in TDI Decompression Procedures, although that manual too shies away from any real specifics).

I have not done the course itself yet (booked in for February), but based on the manual alone, I can't see a whole lot in the TDI Advanced Nitrox course that wasn't covered pretty fully in the basic Nitrox. However (like most people, I suspect) I will be doing the Advanced Nitrox with Deco Procedures, so perhaps when you factor that in, and you have a living breathing instructor in front of you, perhaps hidden knowledge will start to flow...

 

[HowardE]

I should add to my previous post, that at least the advance nitrox course I did (TDI) - did cover in depth the physiology of nitrox, nitrox diving, and give greater definition to the factors that effect nitrox dives, etc.

For the most part though... Advanced Nitrox is Nitrox. The main difference is that all mixtures with > 40% O2 have MOD's shallower than 100 feet. Recreational diving with >40% mixtures takes planning where the details play a very important role, and it's much easier to exceed an MOD. Also the CNS clock is another concern if diving rich mixtures, and high PO2's.

My CCR instructor requires only Nitrox certification and not advanced nitrox certification (while it's recommended, not required). The basic training that we'll be doing (Air Diluent no-deco) is no-deco diving within recreational dive limits on CCR.

I would agree that open circuit no deco diving with rich o2/he mixtures is probably a waste of Helium, and the expense of it. Even at my LDS (fill express) it would cost more than $30 to fill a single tank with a Helium Mixture, and at what result? END's that aren't much different than the dive itself??

So... Advanced Nitrox - it's a good course, and for the most part a stepping stone to other training. There's some good info, which you can get just by reading the book. Read the book, and get the card when you need to do one of the other classes that it's "lumped" with... like Decompression Procedures.

 

[HowardE]

Maybe I am missing something, but when I signed up for the TDI Advanced Nitrox class, I assumed it would be about accelerated deco, but I have read the manual cover to cover and all it talks about is the ability using mixes other than EAN32 and EAN36, and you more number crunching on ppO2 and EAD calculations. Although it mentions accelerated deco, it specifically shies away from it (telling you this is covered in TDI Decompression Procedures, although that manual too shies away from any real specifics).

I have not done the course itself yet (booked in for February), but based on the manual alone, I can't see a whole lot in the TDI Advanced Nitrox course that wasn't covered pretty fully in the basic Nitrox. However (like most people, I suspect) I will be doing the Advanced Nitrox with Deco Procedures, so perhaps when you factor that in, and you have a living breathing instructor in front of you, perhaps hidden knowledge will start to flow...

I asked TDI about this... and here's the reason.

They see that publishing tables with accelerated deco is a big liability. Your instructor will cover procedures in accelerated deco, and TDI (in that book as I recall) recommends using V-Planner or other planning software.

(hope this helps)