TDI Nitrox - differences with PADI

[Pullmyfinger]

I have taken both the Padi and the TDI Nitrox courses. I had to Take the TDI class due to the Padi course not being accepted (by my instructor) as a prerequisite for Advanced Nitrox/Deco procedures.
That being said, the Padi course was adequate in my opinion.
TheThe main differences were that there is much more time and material in the TDI class that is devoted to understanding partial pressures. As was previously mentioned, Dalton's Law and the "T", or "Dalton's Diamond" along with more time spent with formulas are part of the TDI course. None of this is really part of the PADI course. The PADI course does devote some time working the formulas so that you'll have an understanding of partial pressures, it's just explained on one page of their book and presented by the instructor.
The TDI course just spends more time calculating best mix, dose, and depth relationships.
The PADI course covers Enriched Air computers in addition to tables use. The TDI class never really covered computers at all, the emphasis was on tables and formulas.
The PADI course was adequate. The TDI course offers a little more to build on.
To be honest, there really wasn't anything that I didn't already have an understanding of from having taken the PADI class. Things were covered in a little more detail with my TDI instructor.

I will say that my experience with my PADI instructor was minimal. I read the entire book, worked all of the problems, and noted next to each problem what page the information that related to that question could be found in the book.

This was a good thing, because there was really no lecture at all.....my "class" consisted of having my answers graded. There was only a quick discussion of the subject matter.
How to analyze a tank was only explained, never demonstrated. In this regard, my TDI class was a significantly better experience.

I'm sure you would have a more detailed class if you found a PADI class somewhere else. Because as many on this forum love to point out......it's not the agency, it's the instructor.

As I stated, the PADI book was good, and I was able to learn by reading, working the problems and formulas, and just taking an active interest in it.

Another thing I have noticed in regards to nitrox. I've been to Yap and Palau, and I've noticed during both trips that no other divers ever analyzed their tanks. Analyzers were always available, but nobody ever checked their tanks????

Regards,
Mitch

 

[mddyver]

Another thing I have noticed in regards to nitrox. I've been to Yap and Palau, and I've noticed during both trips that no other divers ever analyzed their tanks. Analyzers were always available, but nobody ever checked their tanks????

Regards,
Mitch

Sigh......

I've taken both courses and teach one frequently to a wide range of students with varying levels of competency in algebra and basic physics. I'm also a gas blender and have worked at a very high volume dive resort that filled scores of nitrox cylinders daily.

At some point during the discussion, usually about 20-25 minutes into the class, I inform the students that if they can recall only two points and two points only, they are:

1. Don't plan a dive that exceeds your MOD.

2. If you have any reason to suspect the cylinder you are about to dive has ever contained anything other than air, personally analyze your gas. Never let any dive leader, SO, dive buddy, or situation, etc. pressure you into skipping this step.

What can you do?

Mike

 

[Pullmyfinger]

Hi Mike,

I'm sure it's frustrating for instructors, investing the time and effort leading horses to water.
Some of us horses actually do drink.

-Mitch

 

[romad119]

in Palau. But once the wife and I analyzed our tanks, the rest of the boat seemed to remember that this was a step they should be doing and joined in.

 

[kaerius]

I did it PADI, and my natural reaction is also to go for the calculator before the tables(except for O2 exposure, table only on that)... however I was in one of the last batches of students to use the old manual, from what I've heard, the formulas are gone in the new one(so I guess it's a lot like the SDI one), focusing instead on computers and tables.

On the other hand I did it at the start of my divemaster course and then continued on to OWSI, so I have quite a firm grasp of partial pressures anyway.

 

[sallyliao]

Thanks

 

[knowone]

TDI was actually training, peeps nitrox, well before padi even had panties to pee in, about it.

 

[deepair]

I teach all three. PADI, SDI, and TDI Nitrox. SDI and PADI Nitrox are about the same. Know what is in your bottle, what the MOD is and set your computer. TDI Nitrox is more like the Nitrox I learned from IANTD years ago. It gives a lot of focus on the use of the formulas. This helps the student looking to go further and take the Advanced Nitrox and Deco Procedures a much better foundation. I was not nor am I an algebra expert. Heck I have enough trouble helping my kids with their Homework. But if presented from a good instructor, the formulas make sense and are not hard to use. I actually have 3 DM candidates from other instructors who are planning on taking the TDI nitrox even though they have PADI nitrox. Go figure.

 

[RTee]

As others have said before...a lot of the training is dependent on the instructor you get. I did my Nitrox qual through PADI but with an instructor who bwas very tech minded. Interestingly enough...not only did he have me read the PADI manual but also he lent me one from TDI. We then sat down and went through all the formulaes he could think of.when I did my PADI DM course, he also threw additional reading materials to augment the theory of decompresssion aspect of the course...such as TDI Advanced Nitrox and TDI Deco procs.

Not too long ago I completed those two courses as part of a combined package and my instructor did recognize my PADI Nitrox course as meeting one of the course prerequisite.

 

[tddfleming]

Just finished my TDI Nitrox last night. When I took Padi OW last year, tables were not taught unless you stayed after for a few min and the inst went over them. But had not looked at tables since. I have no knowledge of the Padi Nitrox course to compare to, but I like the TDI book, I did not feel like I was reading an info commerical. I spent a fair amount of time learning the tables before class. I felt that this was the first course that covered any dive planning that I have taken to this point. While we have been teaching ourselves some of dive planning this was the first course that started down that path. The one issue we had with the book (I don't have the book here at work with me) but when it starts into examples of tables, there are three examples that are wrong. Which begins to screw with your head, as I tend to assume they should be correct. The scary part, is that we confirmed our suspension that they were wrong to the inst and it appeared that this was the first time that it has been brought up. Our class does involve 2 dives, but not inst lead. I have to admit, finding a good shop and inst has been the hardest thing around here. There are days that I think it would be much easier inventing some rare formula than finding a good LDS and inst.

Edit::

It was made clear in class to always stay within your MOD and to ALWAYS check your own tanks and to do it upon pickup from LDS. Is it common practice to have your own analiyzer or use the shops upon pick up??