TDI or PADI?

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Whenever I reply I try to do it in a fair, factual way. But since the OP is looking for opinions, I think I'll spill out some of the beans as long as everybody is well aware that this is hearsay and I haven't verified this for myself. I have not seen the book that Peter refers to, but in a conversation someone was telling me that some of the PADI TecRec procedures for deploying a bag involve recommendations to have your buddy go negatively buoyant and hold on to the legs of the bag deployer. Alternatively it was recommended that the deployer wrap his/her legs around a piece of wreck or a rock before deploying the bag. Can anyone confirm or deny this? I find this so tragically comic that it's hard to believe.

I don't know if its in the book or not. But yes this recommendation is in the DSAT tech video and it's really priceless.
 
I don't know either, though I can think of many reasons why - one being local availability. The GUE courses I've done have been great, but have also had to fly in an instructor from overseas to do them. I think that many people don't have the time to dedicate to such an endeavour (or to travel themselves) and look at what is available locally.

I can understand the OPs frustration a few posts back. They've had a fairly clear question, but the majority of responses jump in with the "why don't you do a Helitrox course instead" or other tangential opinion. I'm sure the OP has good reasons for the question they have asked - and answers to a different question are just a distraction.

Thank you Andy you have been very helpful. I agree with what you said about the instructor being linked with the agency. I was questioning PADI and TDI because of availability, and also those just happened to be some of the courses I was researching. Just comparing the general descriptions of the courses from the two agencies one could see differences in the structuring of the courses. I wanted to know more details regarding the differences, and to hear the views of some experienced tech divers and instructors. I also wanted to know if the material taught was actually different. I haven't talked to many tech divers who say PADI puts together a good tech course, I wanted to know why.

My original question was vague and poorly written so it is my fault I didn't get the type of answers I was looking for right away. Next time I will put more effort into my posts.

When a student reads a training manual, only to have the instructor explain that the book is wrong, it brings uncertainty into the students mind. I agree the instructor makes all the difference and an agency comes second. But if the instructor is changing or disregarding training material provided by the agency, or disregarding the way the course is structured a student might question the validity of agency or even worse, the instructor or the material being taught. When I am spending a lot of money and a lot of time to complete this training, I take all aspects into consideration. I haven't decided to do my tech training through one agency or another. Like almost every post stated, I will be basing my decision primarily on the instructor. But while researching I noticed differences in course structures, which lead me to inquire on the matter here. There were a bunch of posts with a lot of good info in this thread. Thanks
 
I don't know if its in the book or not. But yes this recommendation is in the DSAT tech video and it's really priceless.

Page 128. Step 3 of how to deploy a lift bag:

"At the same time, if you can, hold on to something with your legs, or have your team mates hold you down, so you fill the bag as much as possible without it carrying you upward. The more you fill it the better."


Which is of course interesting, as step 2 says you should orally inflate your bag without taking the second stage from your mouth.

I'm not quite sure who at PADI thinks that if you breathe out once into the bag that you can shift the buoyancy of the total system to from neutral to positive. Oh, I forgot, you have to put as much air into the bag as you can so that you can hang off it whilst doing deco. :rofl3:


I don't have my PADI/DSAT instructor manual to hand - I suspect that deploying a lift bag in this way isn't required (by standards), just a recommended technique. But still....
 
Page 128. Step 3 of how to deploy a lift bag:

"At the same time, if you can, hold on to something with your legs, or have your team mates hold you down, so you fill the bag as much as possible without it carrying you upward. The more you fill it the better."

That's some funny sh!t.

You should have responded with this as post #2. Then someone should have locked the thread and made it a sticky. Enough said.
 
When a student reads a training manual, only to have the instructor explain that the book is wrong, it brings uncertainty into the students mind.

There's always going to be something that the instructor disagrees with. For example, there is one TDI performance requirement in the Decompression Procedures course that I'd rather was different. I can't remember exactly how it's worded, but it's essentially 'buddy breathing a deco gas'.

I can see the value of buddy breathing as a skill and teach it in my courses. But in order to have to buddy breathe a deco gas, so many things have gone wrong that should have been avoided. In a team of two, both divers have to have lost back gas and one diver has had to lose their deco gas. That's just unacceptable!

Buddy breathing a deco gas is way down my list of options for conducting an ascent. It is an option, but not that great a one.

I teach the skill in a particular way for a particular reason. Firstly, many tech students I now get have never done buddy breathing... so I first teach them BB using the long hose. For many, it is initially a challenge to maintain constant depth whilst doing it. So for BB a deco gas, I won't use anything too hot. Typically I use 50% but do the skill at 6m. If students can manage to hold a constant depth, great. We then talk about whether they think they can manage to perform a timed ascent from 21m, hitting all the stops along the way. And not run out of gas. Most of my students don't think they could do it - so we then talk alternatives.

Personally, I'd like TDI to change to performance requirement to something a bit more generic like "Perform a controlled ascent from depth requiring the application of a lost deco gas strategy". But hey, I can live with it as it is if I have to.
 
Agreed, there will always be aspects of a course to disagree with. There are things I disagree with in the rec courses I have done and assisted with. But its best if there is a limited number of those
 
I can see the value of buddy breathing as a skill and teach it in my courses. But in order to have to buddy breathe a deco gas, so many things have gone wrong that should have been avoided.

Agreed,but I can think of several reasons why you might CHOOSE to buddy breathe a deco gas.
It's just another tool you might want to use someday.
 
There's always going to be something that the instructor disagrees with. For example, there is one TDI performance requirement in the Decompression Procedures course that I'd rather was different. I can't remember exactly how it's worded, but it's essentially 'buddy breathing a deco gas'.

I can see the value of buddy breathing as a skill and teach it in my courses. But in order to
have to buddy breathe a deco gas, so many things have gone wrong that should have been avoided. In a team of two, both divers have to have lost back gas and one diver has had to lose their deco gas. That's just unacceptable!

Buddy breathing a deco gas is way down my list of options for conducting an ascent. It is an option, but not that great a one.

I teach the skill in a particular way for a particular reason. Firstly, many tech students I now get have never done buddy breathing... so I first teach them BB using the long hose. For many, it is initially a challenge to maintain constant depth whilst doing it. So for BB a deco gas, I won't use anything too hot. Typically I use 50% but do the skill at 6m. If students can manage to hold a constant depth, great. We then talk about whether they think they can manage to perform a timed ascent from 21m, hitting all the stops along the way. And not run out of gas. Most of my students don't think they could do it - so we then talk alternatives.

Personally, I'd like TDI to change to performance requirement to something a bit more generic like "Perform a controlled ascent from depth requiring the application of a lost deco gas strategy". But hey, I can live with it as it is if I have to.

Oddly, I have had to do this very thing. It's worth pointing out that I also had no mask, a missing OPV valve on my wing, a missing deco bottle, and a failed Argon reg on the same dive.


All the best, James
 
There's always going to be something that the instructor disagrees with. For example, there is one TDI performance requirement in the Decompression Procedures course that I'd rather was different. I can't remember exactly how it's worded, but it's essentially 'buddy breathing a deco gas'.

I can see the value of buddy breathing as a skill and teach it in my courses. But in order to have to buddy breathe a deco gas, so many things have gone wrong that should have been avoided. In a team of two, both divers have to have lost back gas and one diver has had to lose their deco gas. That's just unacceptable!

Buddy breathing a deco gas is way down my list of options for conducting an ascent. It is an option, but not that great a one.

I teach the skill in a particular way for a particular reason. Firstly, many tech students I now get have never done buddy breathing... so I first teach them BB using the long hose. For many, it is initially a challenge to maintain constant depth whilst doing it. So for BB a deco gas, I won't use anything too hot. Typically I use 50% but do the skill at 6m. If students can manage to hold a constant depth, great. We then talk about whether they think they can manage to perform a timed ascent from 21m, hitting all the stops along the way. And not run out of gas. Most of my students don't think they could do it - so we then talk alternatives.

Why are you using "live" deco gases (or for that matter expensive backgases) for skills at all? If you are going to be buddy breathing at 6m (21m or 30m, whatever) for skill development you might as well be learning it on air or cheap nitrox 32. Instead of merely talking about what they could or couldn't do, why not have them do a dive to 30m, ascent to 21m and then an abbreviated buddy breathing schedule like 2mins every 3m from 21m to the surface.

Buddy breathing is much more useful than "ditch and don" which is apparently still part of some tech diving curricula.
 
Oddly, I have had to do this very thing. It's worth pointing out that I also had no mask, a missing OPV valve on my wing, a missing deco bottle, and a failed Argon reg on the same dive.


All the best, James

How did you think that dive went?
 
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