TDI vs IANTD

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muddiver

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Does anyone have a good grasp on the difference between TDI and IANTD other than the different alphabet use to identify the two?

And yes I did a search and got nothing of any use. I am evaluating which shop to go with for more advanced education and the two I am looking at are equidistant from my house.
 
Content wise, they're fairly similar, though IANTD probably has a slight edge. TDI is more reader friendly, almost to the point that it puts me off a bit.
 
The top brass at IANTD have serious credentials, and my IANTD instructor trainers have few equals in the dive industry. That said, I still believe it's all about the best instructor for you and the class you are taking.

Whichever courses you are considering, meeting with the instructors who would teach those courses from each shop and discussing the what, where and why of the courses is a good start. Then you might talk with past students that did those courses with those instructors/shops.

The difference in the shops/instructors is likely to be more significant than the difference between the agencies.

Aloha, Steve
IANTD #3611 ;)
 
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IIR there are some differences in things like allowable deco at the Advanced Nitrox stage (100% O2, 15 minutes deco max) as well as differences in training depths for Normoxic Trimix etc..

IANTD does offer a LOT of courses, not sure any other agency has as many, which means lots of diversity. But as has been pointed out, picking the right instructor is going to be more important.

Depending on where you are on the west coast, and which classes you're interested in, you might also check out Naui Tec instructors as well.

BTW - the IANTD technical encylopedia is well worth picking up no matter which agency you go with IMHO.

Aloha, Tim
IANTD #6670 ;)
 
What's TDI?
 
IANTD does offer a LOT of courses, not sure any other agency has as many, which means lots of diversity.

Thats certainly true. So many I find it confusing.

I did Advanced Nitrox/Deco with TDI for 2 main reasons:

1) Got a card for 100% O2 (IANTD was only 50%)

2)Simple course structure:
Advanced Nitrox/Deco (essentially 1 course)
Normoxic Trimix (Good to 200 feet)
Advanced Trimix (Good for 330 feet)

Thats all you need for any OC,non overhead dive.
 
@ Garrobo: Technical Diving International.

I too think the instructor is the most important part of a course. My TDI classes were over taught by quite a bit and I learned a great deal that changed the way I dive. An that was after 1500 dives...
 
My experience has been similar - TDI has a little simpler progresssion of courses and most of it depends on the instructor.

To make it even more confusing you will find TDI instrutors who supplement the somewhat sparse material with IANTD materials and many instructors are crossed over between TDI and at least one or two other agencies.

My impression of the differneces in deco procedures classes betwene TDI and IANTD is that TDI teaches the deco gas portion of the skill set as a distinct topic and skill set with a depth limit (150' when combined with advanced nitrox, and reduced from the prior 170') that reflects more or less practical limits of deep air diving while IANTD's 50% and 15 minute deco limitations essentially limits the diver to single deco gas dives until they advance to trimix certs.

Both have the same basic effect, but different approaches to get there. In my personal opinion, TDI's approach makes more sense for entry level technical divers as they advance and build technical diving experience in progressively greater depths and run times, but it does put a bit more of the responibility on the diver to know their own personal limitations - where in the end it needs to be.
 
Thank you all for the great responses (even the Master Ignoramous Garrob) :D

I think I need to call the IANDI instructor, I met the local TDI instructor and I was put off by his launch into "you need to buy this BP, a doubles bracket and ..."

I would think an instructor would want to introduce a recreational diver to Tech not initiate him right away. I like the idea that TDI has a Intro to Tech course and I think they may have a good idea there. That would be the only thing about IANDI I would like to see different as a shopping entry level student. This is one of the only things I think PADI got right, but I don't buy into their watered down approach to Tech (even being a PADI DM).
 
Thats certainly true. So many I find it confusing.

I did Advanced Nitrox/Deco with TDI for 2 main reasons:

1) Got a card for 100% O2 (IANTD was only 50%)

2)Simple course structure:
Advanced Nitrox/Deco (essentially 1 course)
Normoxic Trimix (Good to 200 feet)
Advanced Trimix (Good for 330 feet)

Thats all you need for any OC,non overhead dive.

IANTD has since changed to allow for 100% - they state it as "PO2’s as high as 1.5 may be used at the decompression or safety stops." So 100% at a 15fsw stop is ok. Though I would teach 50% and starting deco deeper for these types of dives - just makes more sense from a decompression standpoint IMO. But it does take the limit off for getting deco fills for the student after the course is completed.

Aloha, Tim
 

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