Nitrox Class Without Tables or Math...OK?

[Quero]

Learning to use a dive computer to calculate MODs and EANs does not imply that the diver doesn't understand the why of the calculation the computer carries out. A diver can understand the concepts of gas physics and still not need to have the formula etched into his/her brain.

In most places I've been that offer Nitrox in my region of the world, there is a simple table taped to the wall near the O2 analyzer listing a range of Nitrox percentages and the resulting MODs for 1.4, 1.5, and 1.6 ppO2 values. The diver does no calculations. At other places where such a table isn't taped to the wall, I've seen a reminder of the formula taped to a countertop beside a calculator, conveniently placed there for ease of determining the MODs. All the diver does is plug in the numbers and punch the "=" button. Minimal calculation is performed, but not by the diver.

How is using a chart (even a Nitrox RDP) or a calculator significantly different from using a dive computer in terms of understanding the underlying principles, and even in carrying out the calculations? Are some of you really saying that only paper and pencil calculations are valid?

Furthermore, it's an excellent idea to include some practice in certification courses on the use of dive computers for dive planning, but for most agencies, this isn't required.

 

[MikeFerrara]

maybe I'll market a mail order card

From post ten. Now, you were talking about ME being overly sarcastic? You don't call this an attack? You made this personal from the get-go and saying you didn't doesn't change the facts.

It's a well known fact that almost all injuries from aquatic animals are defensive in nature.

You have brought no FACTS to this table: only innuendo about what you think I teach. And no, the facts don't seem to sway you at all.

Hey, I'm done with the thread. You kiddies carry on without me.

Since when do I need facts? Here are some facts for you though.

I disagree with issueing diving certifications without diving with the students.
I think a classroom only class perfectly qualifies students to do whatever they are learning to do as long as they continue to do it on dry land.

I disagree not presenting the theory and/or not verifying that students actually learned it.

SDI, PADI, IANTD or Pete can teach diving classes without math or diving all they want, regardless of what I think.

I can continue to disagree with them even if Pete says I'm not humble, an elitist and need a narcosis session.

I can continue to not use computers or beepers even if Pete thinks if makes me look unhumble.

I can market a mail order card if I want to even though I hope it doesn't make Pete feel hurt.

 

[H2Andy]

 

[MikeFerrara]

In most places I've been that offer Nitrox in my region of the world, there is a simple table taped to the wall near the O2 analyzer listing a range of Nitrox percentages and the resulting MODs for 1.4, 1.5, and 1.6 ppO2 values. The diver does no calculations. At other places where such a table isn't taped to the wall, I've seen a reminder of the formula taped to a countertop beside a calculator, conveniently placed there for ease of determining the MODs. All the diver does is plug in the numbers and punch the "=" button. Minimal calculation is performed, but not by the diver.

Is this why students don't need to learn or is it because they don't learn it?

How is using a chart (even a Nitrox RDP) or a calculator significantly different from using a dive computer in terms of understanding the underlying principles, and even in carrying out the calculations? Are some of you really saying that only paper and pencil calculations are valid?

One obvious advantage to learning to use the math is that you don't need your dive computer with you in order to do it.

An advantage to being able to do the math in your head (at least an estimate) is that you'll be more likely to recognize if the computer is giving you a screwy number.

Furthermore, it's an excellent idea to include some practice in certification courses on the use of dive computers for dive planning, but for most agencies, this isn't required.

Since computers are so popular it does make sense to me to integrate them into a class. It also makes sense to me make sure that students learn the math for things like MOD, PPO2 and EAD.

 

[limeyx]

My computer is pretty much permanently in gauge mode.

You're going to die! Heretic.

 

[Dragon2115]

I seem to remember not being allowed to use a calculator in math class until AFTER I could do the math by hand. Something about proving proficiency and understanding and being able to know that when I punch in 5x5= and the calculator told me the answer was 32, I'd know it was wrong. Point being, if you don't have the basic knowledge foundation and the ability to perform certain skills, how do you know when the computer is giving you bad information?

Having cheat sheets at the dive op is nice, but what if most of your dives are shore dives where there is no Dive op or DM?

Computers are wonderful things, but as with all of mans' creations they malfunction from time to time. I have an Oceanic ProPlus2. In fact I'm on my third one inside of one year. Not knocking Oceanic (my wife's ProPlus2 that was bought at the same time is still going strong), I just had some bad luck with the first two. And that's also why I have a set of analog gauges on my rig as backup. I also know how to use The Wheel for manually calculating multilevel dives since most dive profiles (especially if you're a shore diver) aren't rectangular. But that's me, I just like to know how to do things several different ways just in case one of them fails on me. After all, one of the possible consequences of a mistake in this sport is death. That's enough for me to take it seriously.

Here's a thought though. If we're going to allow nitrox students to rely solely on their computer to provide them the answer to dive planning questions, then following the same logic why bother teaching RDP theory in OW if the student has a computer? As with nitrox the computer will provide them with all the planning information they're looking for with air too. So what's the difference, why not let them use a computer right from day one and just scrap the tables completely?

 

[minnesota01r6]

that very debate is raging right now although it kinda devolved into a DIR pro/con thread now.

Your analogy is flawed - in that the tables are like a slide rule, and computers are like calculators. You can make a mistake with either one, and neither is the "pure form" of arriving at the answer. Computers are just more efficient.

 

[lamont]

Computers are just more efficient.

Computers very precisely model an approximate biological model.

 

[Soggy]

that very debate is raging right now although it kinda devolved into a DIR pro/con thread now.

I just did a search and the term DIR does not appear anywhere in that thread.

 

[Swan1172]

I once heard the analogy made that, "You don't need to understand the workings of an internal combustion engine to know how to drive, so you really don't need to understand the physics of gasses under pressure to know how to dive." However, not knowing what a carb and spark plugs do will probably not kill you. Failing to understand MOD's and PPO can. I can see where agencies are moving away from requiring dives, but I can't see how they can teach Nitrox without tables or math.