Things Scuba Instructors teach that are either bad or just wrong.

[Wibble]

Glad it’s improved since taking the e-learning option. Much preferred the manual as it read better.

Do the current versions allow note taking & highlighting? What about searching and quick reference jumping around?

 

[VikingDives]

It's interesting that one would get different training, depending on the use of different media. I would think the object of training would be to recieve the same knowledge and skills, regardless of reference materials.

The problem was finite time. With self-study "book" students, I had to teach to the final exam to make sure that they passed. They were woefully prepared by the book.

On the other hand, the eLearning students are very well prepared, so now, instead of making sure "no child is left behind" I can teach advanced subjects in that same block of time.

 

[VikingDives]

Glad it’s improved since taking the e-learning option. Much preferred the manual as it read better.

Do the current versions allow note taking & highlighting? What about searching and quick reference jumping around?

For SDI/TDI, I agree with you about the manual. I usually read that first, then go back and do the eLearning (but I'm a book kinda guy).

It's a printable PDF, so you could take notes manually. I don't have adobe installed on my computer, so I'm not sure about doing it electronically... I should upload all the manuals to my kindle and see if note taking is an option there.

As far as searching and jumping around, yes, you can.

As far as PADI, I don't see a way to get access to the written manual.

 

[PR_SMITH]

I am also well over sixty. I always thought that oxygen is very toxic and causes inflammation.
Young cells withsand better this toxicity, in fact when I was a teenager I was trained diving using the pure oxygen CC rebreather (ARO), and we were using it down to 12m (with a p.pressure over 2.2 bar!).
Growing older I became aware of the bad effect of oxygen at higher-than normal pressure, and I try now to minimize the exposure of my cells to oxygen as much as I can.
I am aware that hyperbaric oxygen therapy can cure some diseases, under medical guidance.
But I classify it among powerful drugs: to be used only when needed and after prescription by a medical doctor...
So I would never use Nitrox when not needed, exactly as I do not use any drug if not strictly necessary.

Diving Nitrox at depths appropriate for the % of o2 added to the scuba tank is better for you than not using it. Better not to have the extra nitrogen loading that you get when only diving air.

 

[Angelo Farina]

Diving Nitrox at depths appropriate for the % of o2 added to the scuba tank is better for you than not using it. Better not to have the extra nitrogen loading that you get when only diving air.

Are you an hyperbaric doctor, for saying that exposure to high pressure Nitrogen is more toxic than Oxygen?
The risk of decompression sickness is proportional to how close you go to the NDA limit, not to the partial pressure of Nitrogen.
So, if I always end the dive with adequate conservatorism (say, at 75% of the NDL time limit), there is no substantial advantage breathing an enriched mixture.
Nitrogen is an inert gas, it does not cause significant damage to human cells, even at relatively high partial pressure.
On the other side, high partial pressure of oxygen causes a lot of damage to human cells, and the exposure time is longer (thanks to the extended NDL).
So I leave this approach to others, possibly younger and not so concerned about the toxic effects of oxygen.

 

[PR_SMITH]

Are you an hyperbaric doctor, for saying that exposure to high pressure Nitrogen is more toxic than Oxygen?
The risk of decompression sickness is proportional to how close you go to the NDA limit, not to the partial pressure of Nitrogen.
So, if I always end the dive with adequate conservatorism (say, at 75% of the NDL time limit), there is no substantial advantage breathing an enriched mixture.
Nitrogen is an inert gas, it does not cause significant damage to human cells, even at relatively high partial pressure.
On the other side, high partial pressure of oxygen causes a lot of damage to human cells, and the exposure time is longer (thanks to the extended NDL).
So I leave this approach to others, possibly younger and not so concerned about the toxic effects of oxygen.

I never said nitrogen was toxic at all.
Clearly you do not believe in the benefits of Nitrox; that's your choice. I am not going to waste time trying to change your opinion.

 

[boulderjohn]

The risk of decompression sickness is proportional to how close you go to the NDA limit, not to the partial pressure of Nitrogen.

The partial pressure of nitrogen has a lot to do with how close you come to NDLs.

So, if I always end the dive with adequate conservatorism (say, at 75% of the NDL time limit), there is no substantial advantage breathing an enriched mixture.

The real purpose of nitrox is to extend dive bottom time. If you don't care that your dives are shorter than the dives of people using nitrox, then there really is no advantage for you. For people who prefer longer dives, nitrox provides that advantage.

 

[Boarderguy]

The real purpose of nitrox is to extend dive bottom time. If you don't care that your dives are shorter than the dives of people using nitrox, then there really is o advantage for you. For people who prefer longer dives, nitrox provides that advantage.

Unless of course you're planning on going below 110 fsw for your dive. Air or trimix at that point is about the only option and air is significantly cheaper. Nitrox for above 90 all day long if you can get good and inexpensive fills.

 

[inquis]

So, if I always end the dive with adequate conservatorism (say, at 75% of the NDL time limit), there is no substantial advantage breathing an enriched mixture.

Which NDL time limit are you referencing (air or the relevant EAN)? If you mean to end your dive at 75% of the EAN NDL time, the advantage of breathing EAN is a longer dive for the same DCS risk. If you mean to end your dive at 75% of the air NDL time (or if time is limited by the amount of gas carried), the advantage is less risk for the same time.

 

[boulderjohn]

Unless of course you're planning on going below 110 fsw for your dive. Air or trimix at that point is about the only option and air is significantly cheaper. Nitrox for above 90 all day long if you can get good and inexpensive fills.

I do not understand your point. Why can't I use nitrox to extend dives deeper than 110 feet? Sure, you need a mix with less than 32% O2, but it is still nitrox, and you still get more bottom time.