TDI vs IANTD

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dschonbrun

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I'm interested in pursuing Advanced Nitrox, Deco Procedures, and possibly Trimix this year. The price of certs from IANTD differ significantly from those from TDI taught by the same instructors. Can anyone shed light on why?

Additionally, can anyone offer suggestions as to which one I should pursue?

Thanks,
David
 
I have an IANTD and PSAI Adv Nitrox cert. I did IANTD first, then did PSAI. IANTD is good for 140 feet and a ppO2 of 1.5 at the deepest deco stop. PSAI is good for 150 feet and 100% O2 on deco. If your instructor is PSAI certified, I would do that one. I don't know what the limits are for TDI. Someone else will need to chime in on that.
 
"The TDI Advanced Nitrox Course qualifies divers to use enriched air nitrox from EAN 21 through EAN 100 to a depth of 40 metres/130 feet during dives hat do not require staged decompression."

I would go with TDI.

:)
 
Go TDI through ER/TMX and you're cert'd to 60m...Make sure you have a good instructor, I believe it's much more important to choose your instructor rather than your agency, ask around.
 
IANTD is good for 140 feet and 50% O2 on deco.

Where is this spelled out? I am only aware of a 1.5 ppO2 limit with no fO2 limit for deco mixes. My IANTD Standards document is from Aug 2007. Perhaps there is something newer?

BTW, OP, I got Adv EANx, Deco Proc, and Adv Recreational Trimix all at the same time and the content all flowed together into one nice basket of related concepts. I endorse that approach if you can find the time. There was TDI, IANTD, and some example DSAT content used for the class and I ended up with a mix of cards from TDI and IANTD. My instructor was willing to follow the standards of whatever agency I cared to be certed by for the same price. Ask the instructor - it's a good question and if you don't get a satisfactory explanation, look elsewhere for instruction. Communication between you and your mentor-for-hire should be free and easy. Let this be a test of that!
 
TDI advanced nitrox and deco procedures together will certify you for staged decompression to 150 ft.

TDI's extended range certifies you to 180'.

But, you can add Trimix to the Extended range course which will certify you for normoxic trimix dives to 200'. It is only a few more dives and is an efficient way to get a normoxic trimix cert.
 
Where is this spelled out? I am only aware of a 1.5 ppO2 limit with no fO2 limit for deco mixes. My IANTD Standards document is from Aug 2007. Perhaps there is something newer?

Yeah, I tore apart my IANTD manuals last night looking for that because it didn't sound right to me either after I posted it, and I checked the IANTD website, and I couldn't find it spelled out in the Tek Lite manual or anywhere else. Since then, I have reconfirmed with my instructor that it is ppO2 of 1.5 at your deepest deco depth. Apparently I am told that it used to be 50% max O2 and then it was changed at some point. However, there is still the fo2 limit of 1.5; so I think it works out to about 93% or thereabouts to stay within the 1.5 fractional limit at 20fsw. It basically just means you can't deco with 100% O2 because your first stop is always going to be at least 20'. And so if you are going to do deco, unless you are using your back gas and it is Nitrox (I am assuming it is a suitable MOD) for your deco gas, then you will need to carry something less than 100% in your deco bottle to be at 1.5 or less at 20 fsw if you wish to switch at some point (and because you would like to take advantage of accelerated deco >50% ppO2). If you stay too long and you need to stop deeper than 20fsw, you'll be doing your first stop(s) on back gas too unless your MOD on the deco gas will let you start at a deeper depth, like 30 or 40 feet. So, while the max is not 50% O2, it is not 100% O2 either since you cannot exceed 1.5 ppO2 at your deepest deco stop.

I also had my instructor look up the extended range certs for all three, and they are:
IANTD extended range can take your cert to 180' (54m).
PSAI extended range can take your cert to 180' (55m).
TDI extended range can take your cert to 180' (55m).

These are the most recent standards. I have discovered it can be difficult to ascertain the most current information without an active instructor who has the latest info.

I don't have any TDI certs, but I am looking forward to continuing with PSAI for cave training and this summer for trimix.


Hope this clarifies the earlier post. Thanks for pointing that out.
 
Im planning to get certified with TDI. I am going to be in Grand Cayman in March, I am planning to do my Advanced Nitrox/ Decompression Diving for, according to the course it takes 6 days of diving. I have 11 total diving days, thus, do you think its possible to fit in Extended Range or similar course work?
I honestly think that TDI is better known over IANTD, but thats my $.02. one could make the argument that a recreational diver going into tech diving may want to be certified to a more conservative depth.
 
TDI advanced nitrox and deco procedures together will certify you for staged decompression to 150 ft.

TDI's extended range certifies you to 180'.

But, you can add Trimix to the Extended range course which will certify you for normoxic trimix dives to 200'. It is only a few more dives and is an efficient way to get a normoxic trimix cert.
or you can skip Extended Range and go straight to Trimix (after Adv Nitrox/Decp Procs)
 
You can do go all the way through ER/TMX with 11 diving days if you're really good in the water (if you don't fail any dives), I would just work on some of your theory before hand... In the end, what difference does it really make which organization is known better (I'm TDI, and I like it)...you're going to be learning technical diving.. YOU and your INSTRUCTOR are going to make you a technical diver, not TDI nor IANTD..

I don't know your skill level or how you are in the water, but try to get as many rec dives in as you can before you go do those courses (seeing how many dives you have now)...work on your buoyancy...be able to hover horizontally within .5 ft for 5 minutes no problem.

IMO
 
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