Willem
01-04-2010, 18:44
Hi y'all,
I recently attended TDI's advanced nitrox course and would like to share my opinion with you guys. I hope that there are more people out there who also attended the course and who would like to share or reject my opinion.
The course consisted of 2 parts. A practical part and a theoretical part.
The practical part I have to admit was really good. I did 4 dives using a wing, manifolded twinset (12'ves) and a 7 L stage bottle with EAN35. I had to perform various exercises like doing decostops at 15, 12, 9, 6 and 4,5 meters using a DSMB (which TDI calls "SMB" by the way); I had to turn on and off my bottles, swapping regs, taking on and off the stage bottle, doing gas switches and changing to a spare mask. And all the while maintaining your buoyancy! Really hard but really useful.
The theoretical part on the other hand, proved to be quite the opposite! Never in my life have I beheld such a draconian manual! Poorly written is quite a euphemism I might say. Normally a manual is set up in such a way that it progressively teaches you new material. It is also supposed to be objectively written, not to have supposedly funny comments inserted every paragraph like "those of you who are microbiologists and physiologists out there can research this to a greater extent; the rest of us will be out diving!" HAHAHA, so funny!! It feels like the manual was written by a hobbyist, and not by a professional trainer/teacher.
The manuel kicked off by summing up all the ways in which pressure can be calculated, then launced into a ten page long rant about the differences between the imperial and metric system (TDI is American), then continued describing what nitrogen, oxygen and carbon dioxide is, how we can calculate pressure changes and what decompression is. The reminder of the manual treats how to calculate amongst other things MOD's and nitrogen uptake.
Throughout the manual it is stressed that nitrox mixes higher than EAN40 are mainly used for decompresson purposes. At the same time, the manual stresses that the advanced nitrox course is not a decompression course! But the entire focus of the course is to learn the diver to use up to EAN100! Yes indeed, I got my ticket to use up to 100% oxygen, although the ticket doesn't allow me to use it as the course hasn't taught me decompression techniques.
The tables used are the Buhlmann and US Navy tables. The way in which to calculate your total nitrox uptake, surface interval and remaining time until you launch into decompression modes are in my opinion very cumbersome and they can easily lead to faulty calculations. Not to mention that in the tables pO2's up to 1.6 are used. If you are not aware if this, you might easily misread the table and end up convulsing because you're mix is too high.
All in all, the theoretical part does not cover anything new that I haven't already been taught in BSAC's Ocean Diver and Sports Diver courses. This is supposed to be Advanced Nitrox. And TDI is suppsedly the leading technical agency. It somehow doesn't entirely fit.
Lastly, what is the link between the practical part and the theoretical part? If the course is not a decompression course, then why oh why does the practical side focuses so much on decompression procedures?
Don't get me wrong, I found the practical part really useful. I had never dived with twins before and really enjoyed it. But from an organisation with such a high reputation I would have expected a more balanced course.
I recently attended TDI's advanced nitrox course and would like to share my opinion with you guys. I hope that there are more people out there who also attended the course and who would like to share or reject my opinion.
The course consisted of 2 parts. A practical part and a theoretical part.
The practical part I have to admit was really good. I did 4 dives using a wing, manifolded twinset (12'ves) and a 7 L stage bottle with EAN35. I had to perform various exercises like doing decostops at 15, 12, 9, 6 and 4,5 meters using a DSMB (which TDI calls "SMB" by the way); I had to turn on and off my bottles, swapping regs, taking on and off the stage bottle, doing gas switches and changing to a spare mask. And all the while maintaining your buoyancy! Really hard but really useful.
The theoretical part on the other hand, proved to be quite the opposite! Never in my life have I beheld such a draconian manual! Poorly written is quite a euphemism I might say. Normally a manual is set up in such a way that it progressively teaches you new material. It is also supposed to be objectively written, not to have supposedly funny comments inserted every paragraph like "those of you who are microbiologists and physiologists out there can research this to a greater extent; the rest of us will be out diving!" HAHAHA, so funny!! It feels like the manual was written by a hobbyist, and not by a professional trainer/teacher.
The manuel kicked off by summing up all the ways in which pressure can be calculated, then launced into a ten page long rant about the differences between the imperial and metric system (TDI is American), then continued describing what nitrogen, oxygen and carbon dioxide is, how we can calculate pressure changes and what decompression is. The reminder of the manual treats how to calculate amongst other things MOD's and nitrogen uptake.
Throughout the manual it is stressed that nitrox mixes higher than EAN40 are mainly used for decompresson purposes. At the same time, the manual stresses that the advanced nitrox course is not a decompression course! But the entire focus of the course is to learn the diver to use up to EAN100! Yes indeed, I got my ticket to use up to 100% oxygen, although the ticket doesn't allow me to use it as the course hasn't taught me decompression techniques.
The tables used are the Buhlmann and US Navy tables. The way in which to calculate your total nitrox uptake, surface interval and remaining time until you launch into decompression modes are in my opinion very cumbersome and they can easily lead to faulty calculations. Not to mention that in the tables pO2's up to 1.6 are used. If you are not aware if this, you might easily misread the table and end up convulsing because you're mix is too high.
All in all, the theoretical part does not cover anything new that I haven't already been taught in BSAC's Ocean Diver and Sports Diver courses. This is supposed to be Advanced Nitrox. And TDI is suppsedly the leading technical agency. It somehow doesn't entirely fit.
Lastly, what is the link between the practical part and the theoretical part? If the course is not a decompression course, then why oh why does the practical side focuses so much on decompression procedures?
Don't get me wrong, I found the practical part really useful. I had never dived with twins before and really enjoyed it. But from an organisation with such a high reputation I would have expected a more balanced course.