Should I do Padi Deep before TDI deco & Adv Nitrox

[ianr33]

O.K. Question here about TDI Deco. The MAXIMUM allowed depth is 150. I dont see anywhere in the standards where a minimum is stated. Presumably you could do 40 minute dives at 100 feet on 32% and be within standards ??

 

[Meng_Tze]

O.K. Question here about TDI Deco. The MAXIMUM allowed depth is 150. I dont see anywhere in the standards where a minimum is stated. Presumably you could do 40 minute dives at 100 feet on 32% and be within standards ??

I believe so yes. And it would be one example of deco diving without He in your mix.....

 

[ianr33]

And even GUE would be happy

The knee jerk reaction is that TDI courses always mean deep(ish) air. That certainly can be true,but I dont see that it is required.
With the right instructor you could get certified for 300 feet without ever going over an END of 100.

 

[Randy43068]

Skip the PADI crap.. that's what I'd do.

 

[Steve R]

O.K. Question here about TDI Deco. The MAXIMUM allowed depth is 150. I dont see anywhere in the standards where a minimum is stated. Presumably you could do 40 minute dives at 100 feet on 32% and be within standards ??

Sure you could. I don't see a problem with that whatsoever, and in fact a common approach across the board for a typical entry-level deco class is to perform dives that do not actually require deco, but are treated as a training exercise to include stops.

 

[Rainer]

Sure you could. I don't see a problem with that whatsoever, and in fact a common approach across the board for a typical entry-level deco class is to perform dives that do not actually require deco, but are treated as a training exercise to include stops.

Yup, a buddy of mine did his deco class through TDI, and I don't think they broke 90' for any training dives. He then of course went to 150' for his first post-training dive...

 

[TSandM]

I don't quite understand how taking the PADI Deep specialty will open up sites to you -- Do you dive off boats that require it? I did the Deep specialty, and nonplused the instructor when I mentioned gas planning for a 120 foot dive, because there is NO gas planning information in the specialty. All we had to do was look at our computers to find out what the NDL for 120 feet was.

The only interesting and different thing we did in the specialty was breathe off a hanging deco tank for eight minutes. (I'm assuming eight minutes was because, if you inadvertently go over your NDLs, PADI teaches that you do an eight minute deco stop).

As a stepping stone to true decompression diving, I do not think the class is worth the time and money. If your particular instructor is going to teach gas management, proper buoyancy control under task loading, managing ascents with problems (eg. can you clear your mask without stress while hanging at 20 feet?) then it might be worth while. But that stuff isn't in the PADI class.

It's clear that you want to take the class and like the instructor, and it's unlikely to hurt you in any way, but if it were me, I'd spend my money some other way (like putting it aside toward a good canister light ).

 

[Steve R]

Yup, a buddy of mine did his deco class through TDI, and I don't think they broke 90' for any training dives. He then of course went to 150' for his first post-training dive...

Well, that I would personally find a little suspect, and I would actually have to pull a manual out to check on the correctness of my initial reaction, but it also does prove to me (yet again) another point WRT a very common 'excuse' given by many at TDI that suggest mix is not at all required on this course as 150 is a maximum and they don't need to train their students to max depth.

My point being made here is in the real-world what your buddy did is pretty common (running to that magical maximum depth number on their card "just because".) The depth by itself is not the total issue, it's just in combination with other marginal ideas allowed to run con-current with it.

I myself am not into buying that lame an argument, especially in the face of how I see the results of this class play out in the reality.

I suspect this point is possibly for another thread though.

 

[Steve R]

The knee jerk reaction is that TDI courses always mean deep(ish) air. That certainly can be true,but I dont see that it is required.
With the right instructor you could get certified for 300 feet without ever going over an END of 100.

The point you need to see here is that some agencies happily allow and dare I say promote (by way of their course offerings and outlines) the exact opposite to what you are saying.

Given the bounds of your post above, I suggest to you that the "right" instructor is a very rare person indeed, and the odds of a diver finding this person are long indeed.

I think it's time to stop kidding ourselves here as to how the typical progression is made. It's a little tough to argue "best case possible" when the worst case possible perfectly allowed by standards is pretty damn sad in this day and age.

That's actually why I am a grand supporter of GUE. It's much less of a random toss at the dart board for your money than most others, and by your personal standards above, even their minimum is already above and beyond what you are suggesting. Anything less is not even allowed.

 

[Meng_Tze]

You don't need mix to do decompression dives, you MAY need mix to go deeper. Doing a 70 minute dive at 100ft is a decompression dive, on 32 and O2 it is very doable.

I think too much is focussed on 'mix' rather than doing a decompression dive correctly. While mix has its benefits, we should not equate having mix as equaling of doing a good deco dive.