DM or TEC certification route?

[Doppler]

TDI requires advanced nitrox and decompression procedures before moving on to trimix.

When I did advanced nitrox and decompression procedures, we used ean24 to go to 150' and ean50 as a deco gas.

Personally, this doesn't work well for me, since my options where I fill my tanks are banked ean32, helium and oxygen, so it is difficult for me to get ean24, using 21/35 would be much easier, but I'll wait patiently until and can take the trimix class in the spring before going beyond 100' again

TDI has offered Helitrox Deco for several years... several of us were unhappy teaching students below 30-35 metres on air in the Great Lakes and other cold-water environments and Helitrox was introduced as an option.

Helitrox is a silly marketing term for trimix that delivers a nitrogen load equivalent to air at 30 metres on a dive to the limit of the course -- which is a MAXIMUM of45 metres.

I cannot remember the last time I taught the traditional decompression procedures course and even then took students to a maximum depth somewhere between 30 and 35 metres... And for the record, I have -- in the vast majority of cases -- limited the nitrogen loading for OC students to 3.1 - 3.3 bar for more than 12 years. And I've taught a lot... and during that time, exclusively for TDI.

 

[nimoh]

TDI has offered Helitrox Deco for several years... several of us were unhappy teaching students below 30-35 metres on air in the Great Lakes and other cold-water environments and Helitrox was introduced as an option.

Helitrox is a silly marketing term for trimix that delivers a nitrogen load equivalent to air at 30 metres on a dive to the limit of the course -- which is a MAXIMUM of45 metres.

I cannot remember the last time I taught the traditional decompression procedures course and even then took students to a maximum depth somewhere between 30 and 35 metres... And for the record, I have -- in the vast majority of cases -- limited the nitrogen loading for OC students to 3.1 - 3.3 bar for more than 12 years. And I've taught a lot... and during that time, exclusively for TDI.

I was not aware of the Helitrox Deco course, it wasn't presented as an option to me. I am not an instructor, and took Advanced Nitrox/Decompression Procedures/Nitrox Gas Blender course a month ago, so not really in a position to comment on how things "should" be done, but rather just on what was done in my class.

My personal commentary, was just that, in my personal situation, I am not set up well to do deeper dives without helium, so for now, I am content with staying above 100' on EAN32, and doing mock decompression to practice using a stage bottle until the Spring when I'll take the trimix and advanced trimix classes.

 

[Doppler]

I was not aware of the Helitrox Deco course, it wasn't presented as an option to me. I am not an instructor, and took Advanced Nitrox/Decompression Procedures/Nitrox Gas Blender course a month ago, so not really in a position to comment on how things "should" be done, but rather just on what was done in my class.

My personal commentary, was just that, in my personal situation, I am not set up well to do deeper dives without helium, so for now, I am content with staying above 100' on EAN32, and doing mock decompression to practice using a stage bottle until the Spring when I'll take the trimix and advanced trimix classes.

Don't get defensive, Rob... no need.

You made a statement about what TDI requires... the statement was incorrect. I simply want to set the record straight.

Your instructor teaches the way that makes him or her comfortable and that's fine. I am not suggesting that the program SHOULD be presented one way or another... just that there are options and pointed out what I have found effective.

 

[nimoh]

Don't get defensive, Rob... no need.

You made a statement about what TDI requires... the statement was incorrect. I simply want to set the record straight.

Your instructor teaches the way that makes him or her comfortable and that's fine. I am not suggesting that the program SHOULD be presented one way or another... just that there are options and pointed out what I have found effective.

sorry, did not mean to sound defensive

Was merely suggesting that you are in a much better position to comment on the TDI course structure irrespective of my statements. I agree that my instructor probably made some decisions on what path to take, and perhaps Helitrox would have been an option if I wasn't planning on going on to trimix.

Hopefully the smiley face conveys my tone much better.

 

[boulderjohn]

I agree that my instructor probably made some decisions on what path to take, and perhaps Helitrox would have been an option if I wasn't planning on going on to trimix.

Your instructor may not have had a choice. In order to be a helitrox instructor for TDI, you have to first complete a certain number of certifications at the AN/DP level. If your instructor had not already certified enough people at that level, then helitrox was not an option.

 

[Doppler]

We've strayed a long way from the OP's original question, but it may be of interest to some readers... helitrox is an option for divers who want to dive a little deeper (up to 45 metres) but not beyond... or for whom a full mix class is unattractive... some people seem to be indimidated by 60 metres.

Anyhow, Lynne mentioned courses that introduced helium backmix earlier than PADI's curriculum... with which I am unfamiliar (I only know its CCR programs). There was a debate about this at TDI that ran for several years and the consensus was that the agency would not sanction its use without covering the basics of staged decompression theory and practice... since there is certainly no such thing as a no decompression helium dive.

I pushed for the introduction of 50 percent heliox as a standard deco gas but sadly that idea did not get much traction... but that's a whole other story.

 

[overseas]

(my my, this is getting very interesting...)

 

[boulderjohn]

Anyhow, Lynne mentioned courses that introduced helium backmix earlier than PADI's curriculum... with which I am unfamiliar (I only know its CCR programs). There was a debate about this at TDI that ran for several years and the consensus was that the agency would not sanction its use without covering the basics of staged decompression theory and practice... since there is certainly no such thing as a no decompression helium dive.

This is actually a good discussion for the OP in making choices. I think it is a good idea to look at an entire program before selecting it.

For example, I have technical certifications fro both UTD and TDI. UTD gets divers into helium mixes very quickly, as soon as the diver is done with Intro to Tech. They teach decompression procedures skills in shallow water and have students using helium mix (25/25) on the experience dives below 100 feet. Although they get the diver into a normoxic mix very quickly, they then take a very, very long time and a large number of classes to get all the way through Trimix training. Thus, divers choosing between the two programs should know that one will introduce helium mixtures very early in the instruction but then take a long time to complete it, and the other takes longer to get the student using helium mixes but then completes the training relatively quickly.

The choice is especially important because it can be fairly difficult in some (not all) cases to switch from one program to another.

 

[rjack321]

For example, I have technical certifications fro both UTD and TDI. UTD gets divers into helium mixes very quickly, as soon as the diver is done with Intro to Tech. They teach decompression procedures skills in shallow water and have students using helium mix (25/25) on the experience dives below 100 feet. Although they get the diver into a normoxic mix very quickly, they then take a very, very long time and a large number of classes to get all the way through Trimix training. Thus, divers choosing between the two programs should know that one will introduce helium mixtures very early in the instruction but then take a long time to complete it, and the other takes longer to get the student using helium mixes but then completes the training relatively quickly.

UTD and GUE as agencies, and some instructors teaching for IANTD and TDI (the heliox example) don't hold out on allowing students access to helium fairly early in their curriculums. If students aren't stuck doing 150ft dives in cold water on air, they don't have a need to rush through an air based AN/DP course and onto normoxic trimix to get access to helium. I'd argue this makes them far safer divers. If they don't want to be diving at 200ft they don't have to take a 200ft normoxic class just to get a card granting them access to helium for the dives they enjoy (on heliox) at say 125ft. If these divers are perfectly happy doing 25/25 or 21/35 depth dives (110-160ft-ish) there's no reason for them to be moving on or up the training ladder. The goal is not to get access to the widest range of unlimited depths and hypoxic trimix. The goal is to safely enjoy oneself with the skills appropriate for the dive, regardless if that's at 25ft or 250ft.

 

[Jim Lapenta]

I did Helitrox through the NAUI Tech program which included limited deco. The depth limit for my class was 150. Once we completed the course some of us were offered a "graduation dive" to the St James in Lake Erie on 21/28. 165ft to the sand with the majority of the dive at 150-155. My biggest complaint was having to deco on back gas or 36%.

I've since progressed to be comfortable with 165 as a max depth. I need to do an Adv Nitrox and Deco course. Biggest obstacle is scheduling. Travel is a consideration as well but not huge as there is great diving within a few hours drive. There's also the thing that keeps coming up in that when it looks like I'll get a chance to do the course I end up getting students of my own. Hard to turn down the extra income.

Getting proper training to do some of the dives I'd like to do is high on my list. I've been offered cavern and intro to cave but my only reason for doing those would be for the skills I could transfer to my wreck diving. The other thing that tech training does is make one a better DM. DM's are supposed to have exemplary skills and above average knowledge. I've met a few that had no idea how to properly plan a dive, had less than adequate buoyancy skills, and some couldn't even do a proper weight check.

Tech training will give one all this and more. The most beneficial IMO is the emphasis on accident analysis at the very beginning. It changes the way you look at every dive. I believe it makes safer divers. I'd rather have somone I cared about dive with a newly minted tech diver than with a signifcant number of the new DM's I've seen come out of shops that sell the DM course as another card.