learn from tables or dive computer?

[jbichsel]

There doesn't seem to be much room for debate here. This is taken from a local dive shop website and sounds kind of crazy to me:

Our Courses Are Dive Computer Rated!
Computer rated means that we no longer use tables (Developed in the 1950's as a "sliderule" for calculations). Why? For several reasons,

Safety,
Not for most of us: tables are calibrated for males (Marines) 18-25 years old, in peak physical condition, 95% of us don't fit this profile
Loss of Diving Credit: tables assume you descent to a certain depth, say 30 feet and stay there the entire time. There's not a reef in the world that's this flat.
Ascent rate alarms: tables don't have ascent rate meters or alarms, nor do they beep at you!
Oops I made a mistake!: tables don't beep, or warn you if you are about to do something wrong or are doing something wrong, you have to wait to get to the surface to find your mistake, which is often too late.
Many live-aboards and operators REQUIRE computers because of the increased safety factor

Up to Date Technology: As medicine changes so do dive computers, tables can't be updated by pluggin them in! Engineers haven't used slide-rules in years, neither should we. Or Ask a college student when the last time they did math by hand? (okay some calculus & physics don't count!)
Removes human error

Convenience
Ever see groups of divers scramble for log books and tables at the end of a dive? On a boat? What about just sitting back and relaxing after the dive and let your computer calculate everything for you.
Log book is right in your computer, most are downloadable into your PC!

Fun
We've come to learn how to scuba dive and have fun, if we wanted to spend our vacation scratching our head over math we'd go to an insurance seminar.
You can do more diving in one day with a computer than tables

Value
Get more diving dollar because you can do more dives per day. Example, try doing 8, 80-90 feet dives with tables, it can't be done, but with a computer it can! Just dive Flower Gardens.

Run Tommy, run for your life!

Good night, what kind of lunacy is this?

SoonerBJJ, I think you should post what dive shop this is! If it's in Dallas (assumption based on your profile) I may know who they are.

That is one of the most ignorand and dangerous things I have heard.

I still plan my dives on tables, take the table or Wheel and plan with me, in the event my computer dies. I also like to check my profile at the end of some dives just to make sure the computer is being honest.

Learn on a computer only? They should be run out of town before sundown!

 

[knotical]

Wow! The vote is unanimously in favor of learning tables instead of computers.
So, I’ll venture a minority opinion:

What is the goal? To dive with low DCS risk. This can be done with either tables or computers.
One reputable certifying agency (not mine) teaches entry-level divers with computers instead of tables. I have no problem with that.

What are tables? A representation of a physical/physiological model that attempts to reduce DCS risk. So are computers!
Do you need to know the details of the model to dive safely? No.
How much understanding of the model is necessary for an entry-level diver? Enough to accept that it is wise to follow a reputable model. It’s good to have a basic understanding of on- and off-gassing and the effects of depth and time. This can be learned with a table, a computer, or neither. Dive planning can be done with either.

What’s the big advantage of tables over computers? Cost. Especially if, like me, you dive with a second computer as a backup.

What are the big advantages of computers over tables? Tracking complex multi-level dives, and reducing human error.

Tables can be helpful, but not critical to understanding a specific, or various DCS models. But such understanding is not necessary to dive safely.

I (and my agency) still teach tables. I’ve had positive responses from those students who used the eRDP. We also introduce computers. In an ideal world I’d offer options, tailored to the individual students’ needs.

 

[IwakuniDiver]

What are the big advantages of computers over tables? Tracking complex multi-level dives, and reducing human error.

Everyone is entitled to their opinion and I don't mean to dissrespect yours, but I have a huge problem with this statement.

Being an instructor, you should be aware that, when used properly, tables such as the NAUI, PADI, NOAA, ect, are FAR more conservative than any computer. The only advantage computers really offer is increasing your overal bottom time because it can take into account that 20 minutes you spent at 30 feet before you dropped to 80 for one. I don't see how you think that computers can reduce human error.

I have a computer, and I love my computer. The ease of tracking dives is a real benifit to me but I don't need one to be a safe diver and all my multi-dive, dive plans are done on tables.

Scott

 

[jbichsel]

Wow! The vote is unanimously in favor of learning tables instead of computers.
So, I’ll venture a minority opinion:

What is the goal? To dive with low DCS risk. This can be done with either tables or computers.
One reputable certifying agency (not mine) teaches entry-level divers with computers instead of tables. I have no problem with that.

I understand what you're saying, but disagree in that I think, we should provide the full understanding of DCS, nitrogen loading, outgassing, etc., along with the ability to plan and/or continue diving when the conputer fails. My dive watch has a rapid ascent alarm so if I am a moron and forget to watch the smallest bubbles and go slower, my watch will beep.

When I go Concealed Carry, I do not carry a round in the chamber. Why? Safeties are mechanical devices and can fail. Dive computers are mechanical devices and can (and do)fail. The results of either one failing can be the same.

What are tables? A representation of a physical/physiological model that attempts to reduce DCS risk. So are computers!

True, but tables don't have batteries that can fail, EPROMs that can fail, o-rings that can fail, algorithims that can be flawed.......

The points of failure and much less on tables than computers.

Do you need to know the details of the model to dive safely? No.
How much understanding of the model is necessary for an entry-level diver? Enough to accept that it is wise to follow a reputable model. It’s good to have a basic understanding of on- and off-gassing and the effects of depth and time. This can be learned with a table, a computer, or neither. Dive planning can be done with either.

But if you are NOT teaching tables, I think the students are not even getting the basic hands-on experience of seeing cause and effect that they get from planning dives on the tables. Being able to follow the rows and columns, or turn the Wheel and see a single, multi dive or multi-level profile in front of them, goes a long way towards building a stronger foundation of understanding.

What’s the big advantage of tables over computers? Cost. Especially if, like me, you dive with a second computer as a backup.

Plus, not having the basic hands-on experience of seeing "on paper" what the plan, profile, results are.

What are the big advantages of computers over tables? Tracking complex multi-level dives, and reducing human error.

Yes and no. Tracking complex multi-level dives EASIER, yes. Reducing human error, maybe. After all, dive computers are made by humans. There have been many recalls of dive computers.

Tables can be helpful, but not critical to understanding a specific, or various DCS models. But such understanding is not necessary to dive safely.

Personally, I believe that understanding dive tables, nitrogen absorbtion, outgassing, etc., IS critical to diving safely for a long period of time.

I (and my agency) still teach tables. I’ve had positive responses from those students who used the eRDP. We also introduce computers. In an ideal world I’d offer options, tailored to the individual students’ needs.

Yes, PADI does still teach tables. And the day they stop will be the day I drop them like a hot rock.

All the major training agencies and RSTC seem to be in a continual mode of making dive training easier, less stressful for the students and lowering requirements. I think that we are doing a major disservice to student divers, dive professionals and the industry as a whole by not elevating the standards and requiring a better understanding and level of training.

I liken this issue to cars:

When my daughters get to driving age, I will NOT allow them to have a Corvette as their first car. When they have gained enough experience, knowledge of driving regulations, fundamentals, different driving conditions and have developed a great sense of responsibility, (plus can buy it themselves, pay the insurance, gas, tires, etc.), then they can think about it. But they have to have a foundation to build on first.

To me, not teaching tables first is idiotic and irresponsible. My daughters WILL learn tables and dive tables for a long while before I get them dive computers.

 

[bradshsi]

Wow! The vote is unanimously in favor of learning tables instead of computers.
So, I’ll venture a minority opinion:

What is the goal? To dive with low DCS risk. This can be done with either tables or computers.
One reputable certifying agency (not mine) teaches entry-level divers with computers instead of tables. I have no problem with that.

What are tables? A representation of a physical/physiological model that attempts to reduce DCS risk. So are computers!
Do you need to know the details of the model to dive safely? No.
How much understanding of the model is necessary for an entry-level diver? Enough to accept that it is wise to follow a reputable model. It’s good to have a basic understanding of on- and off-gassing and the effects of depth and time. This can be learned with a table, a computer, or neither. Dive planning can be done with either.

I think what got most of the posters torqued was not the teaching of computers only per se but the hyperbolic BS they used to justify it.

Further, I'd comment on your statements as follows:

Planning is definitely easier on a table than a computer. You can instantly see the effect of different depths on the NDL. This makes it much easier to get a feel for the dive compared to scrolling though a small LCD display.

As others have mentioned, tables can be a good reality check on what the computer is telling you. A black box device like a computer can contain errors or serve up unreasonable results (for example accidentally setting you computer on EAN 36 and then dive with air in your tank... ). I see this particular problem in engineering as well. Newly graduated students tend to trust what the computer tells them and not double check the result against a hand calculation. They need to develop a feel for the expected magnitude of the answer. The old adage garbage in garbage out holds true.

 

[Damselfish]

a few of the things in the ad that aren't misleading are actually true, as far as value and convienience and stuff. But even those miss the fact that learning tables in class by no means prevents you from taking advantage those things later, not to mention doing it more safely because you understand it better.

 

[Thalassamania]

IMHO, Idiots ... folks who know nothing and are flat out wrong!

Get more diving dollar because you can do more dives per day. Example, try doing 8, 80-90 feet dives with tables, it can't be done, but with a computer it can! Just dive Flower Gardens.

vs.

Dr. Karl Edmunds' findings that on a similar series of dives it was easy to get bend even though the computer said that you'd be fine.

 

[MikeFerrara]

IMHO, Idiots ... folks who know nothing and are flat out wrong!



vs.

Dr. Karl Edmunds' findings that on a similar series of dives it was easy to get bend even though the computer said that you'd be fine.

It doesn't even take a doctor to reason that the more dives we do and the more days in a row that we do it, the further we are moving from the ranges where mosty model testing has been done and the further we may be moving from a range where that model will comcloise to predicting what the results will be for us personally...the error may compound, in other words.

For that very reason, every certified diver has probably been presented with material that recommends putting a reasonable limit on repetative dives and taking a break every few days.

Adds like this are corny attempts to take advantage of the natural desire of people to want something for nothing...ie more diving, more safety and less work. How nice would that really be? The divers who buy into this crap have earned their right to a ride in the chamber of their choice at market cost.

 

[ClayJar]

I'll grant you using the computer can reduce some types of errors. Then again I don't see tables being recalled because of a programming error (unlike computers).

Well, then again, there was that PADI RDP recall (due to printing errors), but it *is* a lot easier to verify that all the numbers on a table are correct than it is to verify that a computer's algorithms are perfectly consistent. (Hehe, and since NAUI tables have far fewer numbers than PADI RDPs, they're even *better*, right? )

It's worse than that. Those crazy beepers go off when divers just raise their computer to look at it. The diver may not be ascending at all.

Actually, isn't that beeping the computer scolding them for not being horizontal in the water? Whenever I sweep my arm around to read my computer or gauges, their depth doesn't change. (And I learned very quickly to casually sweep to the side -- pulling them straight up in front of you tends to make more bottom-stirring eddies.)

As regards the original question: Any place that doesn't teach tables is doing a disservice to their students, however, considering how few of those students will likely remember anything about the tables given a few months, any place that doesn't teach computers is not exactly doing a service to their students. (You can't teach *every* computer, but there ought to be a bit more than three photos of ancient computers in the book.)

When I dove with a newly-certified friend, I required them to wear a computer (owned, rented, or borrowed fully-offgassed spare), and we went through a computer orientation before and during the first dive. It made such a very significant impact on their dive safety with respect to ascent rates and stops that I'm hard-pressed to make an exception now. (It's great to be able to control ascent rates and do stops without a computer, but how are you supposed to get your intuitive feel for it all if you have no idea what you're actually doing?)

 

[MikeFerrara]

Actually, isn't that beeping the computer scolding them for not being horizontal in the water? Whenever I sweep my arm around to read my computer or gauges, their depth doesn't change. (And I learned very quickly to casually sweep to the side -- pulling them straight up in front of you tends to make more bottom-stirring eddies.)

Yes and of course some divers have their consols dangling somewhat even when they're clipped. Also, ptting guages on your wrist has them already in front of you where you can see them with no movement at all.

When I dove with a newly-certified friend, I required them to wear a computer (owned, rented, or borrowed fully-offgassed spare), and we went through a computer orientation before and during the first dive. It made such a very significant impact on their dive safety with respect to ascent rates and stops that I'm hard-pressed to make an exception now. (It's great to be able to control ascent rates and do stops without a computer, but how are you supposed to get your intuitive feel for it all if you have no idea what you're actually doing?)

I think that's a good question. A beeper may or may help drive home the fact that something is wrong though I'm not sure what information it provides as to exactly what to do about it. IMO, the place for a diver to learn what they're doing in regard to ascents and descents is in entry level training.

While I wouldn't be inclined to require a prospective dive buddy to use a computer (since I don't use one myself) I would require that they be able to adequately control ascents and descent before I dived with them beyond shallow practice dives designed specifically to correct those skill deficiencies.