Is there any reason to do a Nitrox 'course'?

[boulderjohn]

The sad part is that, although one CAN plan dives using a computer, almost no one does that, either.

One of the reasons for this, I believe, is that few people were ever taught to do so. If you learned to dive with tables, it was not a part of your instruction. Today, if you are taught to dive with computers, using your computer for this purpose is part of the standard training, but that is a recent development, and not everyone takes that course.

Whenever we have one of the bi-monthly threads on how evil it is to teach courses using computers instead of tables, we invariably have at least a few instructors state emphatically that tables are important because they are the only way you can know your NDL before a dive. So we have instructors out there who don't know that a computer will do this, too. We have instructors out there who do not realize that a table cannot be used to pre-plan an NDL for a second dive after an initial muli-level computer dive, but a computer will work for that purpose. If instructors don't know computers can do this, and if it was not taught in any classes until recently, how can we expect the average diver to know this?

 

[MaxBottomtime]

I guess it's only 'significant' if you're one of the hundreds of recreational divers to get chambered each year

Sucks to be one-in-a-million​, I suppose

Is there any evidence that those "hundreds" of divers were diving air only, or that EAN would have prevented their chamber rides? Nitrox will do two things for you. It will give you longer bottom times and shorter surface intervals than air. That's all. For most divers, that's enough reason to dive nitrox, but there is only anecdotal evidence that it is any safer than air.

 

[Dan Sumners]

The fact is that almost no one plans dives with tables any more. Computers are readily available and inexpensive, and tables are so conservative as to be almost punitive, when divers are doing the sort of multi-level dives that are almost ubiquitous. Tables would prohibit almost all of the commonly done shore dives here in Puget Sound!

The sad part is that, although one CAN plan dives using a computer, almost no one does that, either.

Of course, it's not a matter of only using tables, computers are clearly highly beneficial. But your second comment goes to the heart of it; perhaps if people always began by learning to use tables it would make it more likely they'd stay in the habit of planning, whether continuing to use the tables or with a computer, and retain some of it for dealing with emergencies. The biggest computer's inside our skull, it should be made use of!

---------- Post added June 13th, 2013 at 06:29 PM ----------

One of the reasons for this, I believe, is that few people were ever taught to do so. If you learned to dive with tables, it was not a part of your instruction. Today, if you are taught to dive with computers, using your computer for this purpose is part of the standard training, but that is a recent development, and not everyone takes that course.

Whenever we have one of the bi-monthly threads on how evil it is to teach courses using computers instead of tables, we invariably have at least a few instructors state emphatically that tables are important because they are the only way you can know your NDL before a dive. So we have instructors out there who don't know that a computer will do this, too. We have instructors out there who do not realize that a table cannot be used to pre-plan an NDL for a second dive after an initial muli-level computer dive, but a computer will work for that purpose. If instructors don't know computers can do this, and if it was not taught in any classes until recently, how can we expect the average diver to know this?

Whilst it should be included in training, surely it's the responsibility of every person who buys a computer to ensure they know how to use it (and to use it fully) (assuming they want to be safe)?

 

[boulderjohn]

Of course, it's not a matter of only using tables, computers are clearly highly beneficial. But your second comment goes to the heart of it; perhaps if people always began by learning to use tables it would make it more likely they'd stay in the habit of planning, whether continuing to use the tables or with a computer, and retain some of it for dealing with emergencies. The biggest computer's inside our skull, it should be made use of!

Planning the dive using tables is part of the table version of OW courses.

Planning the dive using computers is part of the computer version of the course.

Why would learning to dive with tables teach them to plan the dive using computers, especially if no one ever tells them that computers can do this?

 

[Dan Sumners]

Planning the dive using tables is part of the table version of OW courses.

Planning the dive using computers is part of the computer version of the course.

Why would learning to dive with tables teach them to plan the dive using computers, especially if no one ever tells them that computers can do this?

It wouldn't teach them how to use the computer, no; my suggestion is simply that perhaps learning to plan with tables, and the reiterated importance of doing so, encourages the habit of planning. As I say above, if someone wants to be safe, surely in the end it's up to them to make sure they learn how to use their computer.

 

[dbulmer]

To the OP,
Main reason to do the course is to ensure that the information that you receive originates from an authourative source such as a representative of a diving agency (aka instructor).

In practical terms there's not much to basic Nitrox as I think you may have seen - in the UK you may be asked for a card at some shops where you are an unknown. Having the card is practical common sense really - to avoid denial of the gas both here and abroad.

 

[DevonDiver]

..plan with tables, and the reiterated importance of doing so,

What is the importance of 'planning with tables'?

...encourages the habit of planning.

You can plan dives equally well on a dive computer. This can be encouraged just as effectively... and is more applicable to the diving habits of the majority.

IMHO, it's important to reiterate the importance of effective dive planning during training. That is all. The method used for training that dive planning should reflect the method to be used by the student in their subsequent post-course diving. There's a certain logic to that...

...surely in the end it's up to them to make sure they learn how to use their computer.

I don't see it. Divers pay for training to use their equipment - for the majority, that equipment now includes a dive computer. Why would agencies/instructors neglect to train that most critical piece of equipment???

Is there some logic that I'm missing which makes self-tuition on dive computers preferable to integrating effective training into existing courses?

 

[Dan Sumners]

What is the importance of 'planning with tables'?

So you learn how to plan when a computer isn't available, and maybe you'll retain more information too because it's all in front of you. Plus, you may start to see patterns in the data, which is also helpful. And I think this will all increase safety.

You can plan dives equally well on a dive computer. This can be encouraged just as effectively... and is more applicable to the diving habits of the majority.

Sure, but 'habits' can be good or bad.

I don't see it. Divers pay for training to use their equipment - for the majority, that equipment now includes a dive computer. Why would agencies/instructors neglect to train that most critical piece of equipment???

Of course, if agencies can include computerv training all the better, but I just don't think it should replace the use of tables, for the reasons given above.

Is there some logic that I'm missing which makes self-tuition on dive computers preferable to integrating effective training into existing courses?

No, not if the training can include both. But if it can't, I feel it should include table training. And, as I say, if the diver wants to use a computer, it's surely up to them to ensure they know how to use it, if they want to be safe.

 

[Edward3c]

So you learn how to plan when a computer isn't available, and maybe you'll retain more information too because it's all in front of you. Plus, you may start to see patterns in the data, which is also helpful. And I think this will all increase safety.

For most if their computer dies, etc they will just hire one from the dive operator. Please don’t think the way we dive in the UK is the way the rest of the world dives, it isn’t.

I had an Ocean Diver trainee last Saturday with their own computer. Therefore when running through the dive plan I got them to use their computer to confirm the maximum No-stop time at the desired depth, plus the just deeper scenario. Its how they’re going to dive so why force Tables on them. From my experience of running BSAC DTP training events over the last number of years is most divers have forgotten how to use Tables. The unfortunate thing is, most don’t know how to use their computers to plan the next dive, they jump in and wait for the display to tell them what to do.

Dives planned to include deco-stops are a bit different as most low-end computers don’t include this function, but more and more on the market are.

No, not if the training can include both. But if it can't, I feel it should include table training. And, as I say, if the diver wants to use a computer, it's surely up to them to ensure they know how to use it, if they want to be safe.

BSAC’s Open Water lesson OO5 allows trainees to plan the dive with a computer; there is a Duty-of-Care on both the instructor and BSAC to ensure the individual understands what the computer is telling them. In the same way we don’t give someone a ‘aqualung’ (there goes my age) and say “learn how to use it yourself” we teach them.

 

[DevonDiver]

Is there any evidence that those "hundreds" of divers were diving air only, or that EAN would have prevented their chamber rides?

I'm sure there is evidence/statistics of the breathing gas used, when dives have led to hyperbaric treatment. I don't know what those statistics are though.

As for whether nitrox might have otherwise prevented DCS occurrence on any given air-diving presentation... that could be modeled I guess - but it'd be pure speculation.

Nitrox will do two things for you. It will give you longer bottom times and shorter surface intervals than air. That's all.

I must be misunderstanding your point, because I can't believe you wouldn't understand the intrinsic connection between bottom time duration and nitrogen absorption.... The relative level of nitrogen on-gassing and off-gassing being the crux of whether DCS symptomatic bubbles occur...

If you have less nitrogen inside, you have less risk of bubble formation in any given scenario. Nitrogen leaving saturation at a rate exceeding its transport from the body being the root cause of DCS. That might easily be interpreted as 'less risk of DCS'.

Again, the intrinsic link between the level of nitrogen saturation and DCS risk is well understood.

In addition, there are known benefits in respect of increased PPO2 in limiting and/or collapsing bubbles that may have begun to form. Again, this might easily be interpreted as 'less risk of DCS'.

So you learn how to plan when a computer isn't available,

Having dived in dozens of countries across several continents over 22 years.... I think there's FAR more likelihood of encountering a spare computer rather than a spare plastic table on a dive boat/dive resort etc.

Most people I see don't even have a usable timing device - they don't wear watches (smartphone generation) and/or don't have dive-capable watches. So tables as back-up would be pretty useless to them, even if available...

...and maybe you'll retain more information too because it's all in front of you.

I retain information just fine from a computer. It's "in front of me" just as much as a plastic table.

Are you sure that your issue isn't just unfamiliarity with computer operation. I just don't see any difference between plastic (analogue) or electronic (digital) tables - other than the in-water flexibility offered by the digital. It's all just algorithms... and both methods offer easy and precise dive planning according to those numbers.

It doesn't get more complicated than; X meters for Y minutes, then Z minutes on the surface, allowing a further E minutes at F depth on the next dive...

...you may start to see patterns in the data, which is also helpful. And I think this will all increase safety.

Why do you think that?

Does a plastic table provide more "patterns in data" than a computer downloadable graph showing actual calculated tissue compartment saturation across the length of a dive profile, in relation to actual depth and duration?

Really, this argument doesn't have any more logic than demanding a return to the tuition of medieval abacus in maths class. It's an old technology, superseded by the digital age... modern tools do the same functions and more... and it, in reality, reflects the way most people choose to do it.

Why not continue this discussion by paper-mail and stamps... if you really don't appreciate the benefits of electronic mediums and feel the need to have something tangible 'in front of you'? Or would you acknowledge draw-backs to that suggestion?