PADI tables finally going away?

[cloudflint]

I believe it was in a past thread that someone posted a link to an article on World War II research focusing on diver tolerance of toxicity (such as O2 toxicity) when diving. If memory serves, the same individual making much the same dive (e.g.: depth, exercise) can have a wide variation in susceptibility to adverse effects.

Tables don't give you credit for time spent at shallower depths, at least from what we did in PADI OW when I took it over 4 years ago. I'm aware some people train as 'multi-level divers,' but I don't plan in advance just what 'depth plateaus' I'll use, or for how long. Training in a quarry I could, but not meandering around the reefs in Bonaire.

Richard.

Yeah different people can have difference susceptibility to the bends even day to day. Thats why they would put in say a hundred divers at that depth for that time then bring them up and if any of them got bent they would know that they would need to reduce the time more to account for people who could be more susceptible. Thats one of the reasons why i say i dont trust the mathematical tissue models, there are so many variables that its impossible to take them all into account.

Most tables will use a square profile, so it assumes that you spent all dive at the deepest point. I find that to be both an advantage and a disadvantage compared to computers as tables will be more conservative on certain dives if you are only at your max depth for a short amount of time. Its handy to get the added time that the computers bring if im going on holiday and going to be diving most of the week however so in that case i generally will use a computer. For my regular diving in the cold dark waters around where i live on the outher hand i find it comforting to have the added safety margin that the dive tables bring.

Im not sure however if i had only been trained on the PADI tables whether i would use them or a computer.

 

[Kevrumbo]

Read This Kev. Please look at our statements. You have simply regurgitated a statement that you contend to be true with little to no support. You made a contention, using a fallacious analogy and I called Shenanigans. As pious as it might sound your analogy is so far from reality that it made me laugh. Trivial semantics? My opinions? Dude... tables just aren't analog. You're completely wrong on that. Go look up analog at Dictionary.com | Find the Meanings and Definitions of Words at Dictionary.com and see what it actually means. I triple dog dare you. Calling tables "analog" is a gross misrepresentation based on your ignorance of what analog actually means. Now, they are "tabular", but they are not analog. Let me save you some time:

From www.Dictionary.com:

an·a·log   [an-l-awg, -og]
–adjective
of or pertaining to a mechanism that represents data by measurement of a continuous physical variable, as voltage or pressure.

Like PDCs, tables are theoretical: they measure nothing.
Like PDCs, tables are derived from algorithms based on several models of tissue groups.
However, your SPG is an analog gauge because it measures a continual physical variable with a pointer (mechanism). See the difference? Analog does not mean "not digital". Next you'll be referring to a pencil as an analog recording device. My double Shenanigans stands. You would do well to move away from the myths surrounding dive tables as some type of Holy Grail. Like a PDC, they are nothing but a tool, albeit a less useful tool for me than my PDC.

For me, the biggest difference between tables and PDCs is that we remove a substantial amount of human error from the situation. There is no need to rely on the inaccuracy of a human remembering when they splashed and how deep they went. Moreover, there are no fingers to draw a line with sideways, down, to the back and back over. The input is automatic and free from human error and the output is derived electronically from the very same algorithms and with greater speed and precision.

Pardon me for bringing this up, but weren't you bent by making a simple miscalculation? That's what someone told me, and I have no idea if there is any veracity to the claim. If you were, then that would lend a lot of credence to my contention that PDCs remove a lot of human error.

Let's face it. The biggest detraction leveled at PDCs is the phobia that somehow and at sometime they will fail. Guess what? The human mind fails a thousand times more often than any PDC. Our minds are so multi-tasked that it's no wonder that they do. When I go on a dive, my mind is focused on looking at my students, the pretty fishies or hunting. That's why I have a dedicated instrument to record my dive and to give me feedback on all of my limits: air, depth and time. I am certain that there are those who feel more comfortable with their tables and devoting a lot of their mind to tracking their NDL. That's fine! Just don't act like you are a better or more conscientious one because of it. That's just Shenanigans.

As for PADI moving away from tables: GREAT MOVE! It's time we taught students to use the gear they will be using during their diving. MOST people use a PDC, so it makes sense that we train them to use it well from the very beginning.

You infer all the additional rant above, again from my quote below>?

Quote:
Originally Posted by Kevrumbo

The basic digital calculator is a convenience but should never precede or replace fundamental knowledge & comprehension of analog four-operator arithmetic by hand.

The basic personal dive computer (PDC) is a convenience but should not precede or replace fundamental knowledge & comprehension of analog dive tables.

Excuse me . . .but I believe from an Education perspective, teachers are still introducing fundamentally at the primary/elementary school level the concepts of four-operator base 10 arithmetic (Addition, Subtraction, Multiplication and Division) and how to perform these computations in an analagous method by hand, before learning to use the convenience of a digital hand calculator or desk/laptop digital computer. Similarly based on this fact; my honest opinion implied in my simple quote above, from the wisdom and experience of an educational & learning environment spanning elementary school through University; that classic tabular dive table theory with analog computation solutions by hand should still be taught fundamentally at the basic OW level, before learning the operative conveniences of a Personal Digital Electronic Dive Computer. Doesn't this make more sense than your spurious rant above, Pete?

Pete . . . obviously your points quoted above are illusory, illogical, misleading, trivial and inflammatory arguments, with malicious insinuation & innuendo regarding my DCS Accident on your part . . . I call bullscat on you Pete (and borderline abuse with your insulting suppositions out-of-context in hindsight with reference to my accident, by the TOS of this Board--shame on you NetDoc!)

 

[boulderjohn]

You infer all the additional rant above, again from my quote below>?

Excuse me . . .but I believe from an Education perspective, teachers are still introducing fundamentally at the primary/elementary school level the concepts of four-operator base 10 arithmetic (Addition, Subtraction, Multiplication and Division) and how to perform these computations in an analagous method by hand, before learning to use the convenience of a digital hand calculator or desk/laptop digital computer. Similarly based on this fact; my honest opinion implied in my simple quote above, from the wisdom and experience of an educational & learning environment spanning elementary school through University; that classic tabular dive table theory with analog computation solutions by hand should still be taught fundamentally at the basic OW level, before learning the operative conveniences of a Personal Digital Electronic Dive Computer. Doesn't this make more sense than your spurious rant above, Pete?

Pete . . . obviously your points quoted above are illusory, illogical, misleading, trivial and inflammatory arguments, with malicious insinuation & innuendo regarding my DCS Accident on your part . . . I call bullscat on you Pete (and borderline abuse with your insulting suppositions out-of-context in hindsight with reference to my accident, by the TOS of this Board--shame on you NetDoc!)

I frankly had trouble understanding your point. It seems to me that you are arguing that tables need to be learned before computers based on an analogy between that and how teaching is done at the elementary level, that is, students are taught to do arithmetic on their own before being allowed to use a calculator, do students should learn to use tables before learning to use a computer.

If that is what you are saying, it is a false analogy. You have to compare the purpose of the tasks, and when you do you see a fundamental difference.

The purpose of math instruction at the elementary level is to teach students how the math works and to do it on their own. It is considered an important skill that they will use even if they are proficient with a calculator. Math educational experts have made it clear that the ability to perform these tasks fluidly and quickly on your own without having to refer to a calculator is critical to developing later skills. Therefore, it makes sense to teach that first. The calculator is taught later because it has a fundamentally different function--it performs more complex calculations more quickly and very accurately so that students are able to do higher order tasks without having to spend time on those functions--it makes learning the higher order tasks much more efficient.

The purpose of learning tables is to be able to calculate a proper dive and ascent profile. That is also the purpose of using a computer. They are two different ways to do the same thing. If the student is planning to use a computer in the future, it serves no purpose to learn the table.

And don't argue that learning the tables is needed to explain decompression theory. It is not. Mark Powell somehow managed to explain deco theory in great detail in his book without once teaching how tables worked.

 

[The Chairman]

You infer all the additional rant above, again from my quote below>?

I didn't infer... I stated Shenanigans quite clearly.

Excuse me . . .but I believe from an Education perspective, teachers are still introducing fundamentally at the primary/elementary school level the concepts of four-operator base 10 arithmetic (Addition, Subtraction, Multiplication and Division) and how to perform these computations in an analagous method by hand,

You are not teaching these people how to calculate their NDL or deco obligations by hand. That would require calculus and a great deal of tissue loading theory. Obviously, this is way beyond the ken of most divers including you and me. Fortunately they have "simplified" the process by creating a table that, in the case of PADI, has been generated using digital devices. :shocked2: It is only a tool and was a significant step in the evolution of safe diving. The PDC is an even simpler, faster and more accurate tool to use and is being used with far greater frequency by the average recreational diver. In the same way that the calculator replaced the sliderule, so the PDC is replacing the table with a few die hard table users telling us how we are all gonna die (or our brains will rot) because of the change. We get it: you don't like (trust?) change!

before learning to use the convenience of a digital hand calculator or desk/laptop digital computer.

Or before learning how to use a slide rule. Your analogy is faulty. The table is not the "ROOT" of deco theory. It is not the equivalent of solving arithmetic computations by hand. This is one of the myths that need debunking and I am amazed that you can't see that. A table is nothing but a tool, just like a PDC, to determine your liability for DCS. It is not analog and it is not essential for recreational diving anymore. That is my honest opinion and is demonstrated hundreds (if not thousands) of times a day by the vast majority of recreational divers who use a PDC.

Similarly based on this fact; my honest opinion implied in my simple quote above, from the wisdom and experience of an educational & learning environment spanning elementary school through University; that classic tabular dive table theory with analog computation solutions by hand should still be taught fundamentally at the basic OW level, before learning the operative conveniences of a Personal Digital Electronic Dive Computer. Doesn't this make more sense than your spurious rant above, Pete?

It wasn't a rant: it was a correction and it stands. Please Google "Analog Computation" and read. It has to do with using electricity along a wire of standardized resistance such as nichrome. I did experiments with it in grade school and I built an electric analog slide rule. Again, analog does not mean "not-digital". It has nothing to do with doing calculations via pen and paper, and funny enough: the tables don't require that either except under one circumstance. I am sorry this angers you so, but I didn't invent the word: I just know it's proper usage.

Pete . . . obviously your points quoted above are illusory, illogical, misleading, trivial and inflammatory arguments, with malicious insinuation & innuendo regarding my DCS Accident on your part . . . I call bullscat on you Pete (and borderline abuse with your insulting suppositions out-of-context in hindsight with reference to my accident, by the TOS of this Board--shame on you NetDoc!)

FWIW, I have no particulars on what happened with your DCS incident and indicated as such, but I can see that the mere mention of it also angers you greatly. I was hoping you could share the particulars in that it might bear on the discussion at hand. I didn't realize that you were so sensitive about it, and you can consider the question withdrawn with my apologies. I will be sure to pass your displeasure along to the person who told me.

 

[Kevrumbo]

Apology accepted Pete!
Regards and Good Diving Karma Always to You. . . !

I frankly had trouble understanding your point. It seems to me that you are arguing that tables need to be learned before computers based on an analogy between that and how teaching is done at the elementary level, that is, students are taught to do arithmetic on their own before being allowed to use a calculator, do students should learn to use tables before learning to use a computer.

If that is what you are saying, it is a false analogy. You have to compare the purpose of the tasks, and when you do you see a fundamental difference.

The purpose of math instruction at the elementary level is to teach students how the math works and to do it on their own. It is considered an important skill that they will use even if they are proficient with a calculator. Math educational experts have made it clear that the ability to perform these tasks fluidly and quickly on your own without having to refer to a calculator is critical to developing later skills. Therefore, it makes sense to teach that first. The calculator is taught later because it has a fundamentally different function--it performs more complex calculations more quickly and very accurately so that students are able to do higher order tasks without having to spend time on those functions--it makes learning the higher order tasks much more efficient.

The purpose of learning tables is to be able to calculate a proper dive and ascent profile. That is also the purpose of using a computer. They are two different ways to do the same thing. If the student is planning to use a computer in the future, it serves no purpose to learn the table.

And don't argue that learning the tables is needed to explain decompression theory. It is not. Mark Powell somehow managed to explain deco theory in great detail in his book without once teaching how tables worked.

Exactly my point Boulderjohn, notwithstanding your curiously strange conclusion of a false analogy, and not advocating the use of dive tables as a basic applied reference for decompression theory and planning . . . again heuristically and from an Education & Learning perspective IMHO, I beg to differ: my analogy is valid.

Further motivation:

Quote:
Originally Posted by Jarrod
<snip>From my perspective all divers need to learn and be familiar with tables. I regularly use tables to this day as guesstimates are silly with aggressive and/or complex decompressions. In general I don't accept the idea that using a computer or any iteration of ratio relieves this responsibility. I believe divers should understand where this information comes from, be able to work a basic set of tables and understand how to make basic comparisons between strategies and/or algorithms. Various methodologies (ratio, PC, other tables, computers etc) are reasonable choices to be made by educated divers but I think they should be able to refer to a basic foundation to make comparisons with a relatively well known baseline. This is the reason we are teaching tables (along with our other strategies) and why we refer to Decoplanner when teaching ratio deco. Our tables are not meant to be aggressive and when paired with a slow ascent and the stops we require as part of our training I think they represent a fair compromise. They are basically NOAA tables in origin and build upon a well proven historical record with current GUE principles interwoven.<snip>

Originally Posted by Kevrumbo
USC Catalina Hyperbaric Chamber

There's no digital computer controlling the hyperbaric chamber, nor tracking the N2 loading of patient, tender & physician here --it's all human analog control of chamber machine, pressure mechanics & breathing gas delivery plumbing; manual base 60 arithmetic for elapsed time calculations; handwritten data-logging, patient charting and hard copy referenced dive & treatment tables --the rationale being that an emergency hyperbaric oxygen treatment at this remote onsite Advanced Life Support Facility at the west end of Catalina Island should never depend upon primary electronics that may be incapacitated by a mainline power failure. [Jarrod and GUE have a similar philosophy regarding electronics vs manual control in the operation of Rebreathers].

You must know and already be familiar with the basic methodology of working with dive tables (especially this one: http://college.usc.edu/hyperbaric/documents/hugi.pdf), if you ever want to work/volunteer at the above recompression chamber. (It's also good in general to be familiar with tables as well, should you ever have to be treated in one ). . .They'll always be useful despite rhetorical attempts to label them as archaic or obsolete compared to the algorithms and convenience of the modern dive computer --(got that Pete /NetDoc??)

The point is from my perspective and experience:

A good grounding in fundamental dive tables will always serve you, especially when that dive computer --or that laptop/desktop/PDA computer loaded with Decoplanner software-- goes kaput . . .(or you screw-up with a "silly guesstimate, aggressive and/or complex decompressions" on your Ratio Deco profile).

http://www.scubaboard.com/forums/5268307-post60.html

 

[Kingpatzer]

As for PADI moving away from tables: GREAT MOVE! It's time we taught students to use the gear they will be using during their diving. MOST people use a PDC, so it makes sense that we train them to use it well from the very beginning.

I do wish there was more emphasis and practice planning dives with a computer encouraged in the course, however.

 

[Kingpatzer]

Kevrumbo, can you explain how you think computers are DIFFERENT from tables when it comes to planning a dive?

Aside from my computer being more conservative, the only real difference is that tables don't handle depths other than those that end in zeros.

 

[Kevrumbo]

Kevrumbo, can you explain how you think computers are DIFFERENT from tables when it comes to planning a dive?

Aside from my computer being more conservative, the only real difference is that tables don't handle depths other than those that end in zeros.

I'll only offer how I utilize the relative convenience of one versus the other: for multi-level recreational dives per day, I use a Vytec digital dive computer, and pre-plan the dive implementing the Minimum Deco Algorithm & Table, manually computing on-the-fly to update if necessary. (Have a back-up old PADI RDP Wheel analog computer stowed in the divebag as well! ). Been recreationally diving nitrox32 or air now since 1999.

For square profile deep mixed gas technical dives with mandatory deco stops, I put the Vytec dive computer into gauge mode only and use the Ratio Deco Algorithm & Table, along with referencing the WKPP Deep Stop Table for pre-planning and implementing on-the-fly as needed. Maximum two deep technical dives per day with 3hr SIT. Doing technical dives, mostly overseas in SE Asia/Micronesia on WWII wrecks since 2005.

As for tables unable to handle depths not ending in zero (i.e. the cardinal numbers of 10', 20', 30' etc. in the Imperial System; and 3m, 6m, 9m etc. in Metric) --I play it conservative for planning purposes by referring to the next deeper depth (or on-the-fly calculations by depth averaging biased to max depth). . .

(Refer to attached pdf on Ratio Deco, and take the class if you even think of utilizing this method)

 

[The Chairman]

Of course, we are talking about entry level recreational/non-deco Scuba classes here. Even then, most tech divers I know plan on their PC, print the custom table out and use a PDC as a back up.

 

[Kingpatzer]

I'll only offer how I utilize the relative convenience of one versus the other: for multi-level recreational dives per day, I use . . .

You didn't answer the question.

Let me explain how I see the difference.

On a computer when planning a dive, a diver selects the depth and/or time they wish to dive, and then take the requisite information about the other off of the computer. That is, if they want to be under for no more than 30 minutes, they obtain what my maximum depth can be. If they want to dive to 99'/30m, they obtain what my maximum time at depth can be.

When using a table, they DO THE VERY SAME THING!

In other words, when it comes to dive planning, the functions are identical. The only difference is the steps involved. Depending on the computer this can be simpler or more difficult than using the table. The procedures, that is the step by step instructions, for reaching point A from point B are different; but, the process, that is the big picture goals, is identical.

Since we're talking about dive planning here, and not dive execution, I can't even figure out what people see as the difference.

We aren't talking about just jumping in the water and diving the computer without planning. We're talking about planning a dive.