Nitrox Class Without Tables or Math...OK?

[Soggy]

Why stop there? I mean, those equations and tables were derived from human and animal testing. I say that unless you have actually put a goat or a navy diver into a chamber, you aren't qualified to dive.

Come on, get real guys. There is a huge difference between learning a simple formula that illustrates the direct relationship between the gas laws and MOD, learning baseline figures that allow you to sanity check a potentially buggy and easy to misuse computer vs learning differential calculus. People way smarter than us did this research a long time ago and there are certain baselines that we no longer need to reinvent. My dumb Vyper doesn't even allow me to get an accurate MOD since it uses some idiotic and demonstrably *incorrect* formula for calculating MOD. I think it uses 32 fsw as 1 ATA or something, but comes up with a MOD of 107 for 32% at 1.4. I would only know that it is incorrect if I knew how to do the *simple* math myself. It is entirely possible that there is some setting in there that I have been unable to find, but I no longer care because I know that the computer doesn't provide me with any information that I don't already know.

You all just set up a slip-'n-slide on Mt Everest and are headed down the mountain fast.

I can't believe I'm still posting to this thread, but it's 5AM and I've got a killer cough and can't sleep, so what better to do that argue on the Internet.

 

[minnesota01r6]

So soggy, your complaints are:
1) your computer is too conservative (too safe for you?)
2) you don't know if you are properly using it, but you don't care
3) you cannot memorize what MOD for EAN 32 and 36 are, and then apply that knowledge as a guide for other mixes instead of using formulae.

I will remind you that someone as unfamiliar with the formulas as you are with computers has an equal chance of messing things up.

Most of the people in this thread harping on situational awareness somehow think it is impossible when it comes to computers.

 

[Soggy]

No, not even close. Try again...

So soggy, your complaints are:
1) your computer is too conservative (too safe for you?)
2) you don't know if you are properly using it, but you don't care
3) you cannot memorize what MOD for EAN 32 and 36 are, and then apply that knowledge as a guide for other mixes instead of using formulae.

I will remind you that someone as unfamiliar with the formulas as you are with computers has an equal chance of messing things up.

Most of the people in this thread harping on situational awareness somehow think it is impossible when it comes to computers.

 

[Rick Murchison]

So soggy, your complaints are:
1) your computer is too conservative (too safe for you?)
2) you don't know if you are properly using it, but you don't care
3) you cannot memorize what MOD for EAN 32 and 36 are, and then apply that knowledge as a guide for other mixes instead of using formulae.

I will remind you that someone as unfamiliar with the formulas as you are with computers has an equal chance of messing things up.

Most of the people in this thread harping on situational awareness somehow think it is impossible when it comes to computers.

C'mon, gang, let's inject a little reason in here. All Soggy (and I) have been touting is that knowing the math, knowing what's reasonable and what isn't reasonable, based on current deco theory, is necessary to be able to tell if a computer is lying to you or not. We think that's important because computers do lie from time to time, and you can get in trouble if you don't know enough to catch it when it happens.
The other point he (and I) has is that you cannot depend on computers to warn you when you're exceeding some limit by alarms, because (1) by the time the computer alarms the event is in the past, and/or (2) you may not hear or see the alarm. It is therefore incumbant upon the prudent diver to have enough situational awareness that the alarms become superflous, at most a simple confirmation of what the diver already knows.
As for conservatism, I often dive a SUUNTO and an Oceanic side-by-side; the Oceanic makes the SUUNTO look like a paranoid nanny. Which one's "right?"
Me, I stick with what I know is reasonable from my own math and tables calculations and make sure I don't exceed that; the computers are backup.
Rick

 

[minnesota01r6]

All that I (and others) have been trying to say is that:

knowing what's reasonable and what isn't reasonable

does not require

knowing the math

Again, if you dive anything more advanced than a basic OW dive on nitrox, then you should have more than just a computer, but for a simple OW dive, you and your buddy independantly planning the dive on your respective computers and comparing the answers provides more than enough margin of safety.

 

[Swan1172]

Actually, you ARE agreeing with me. The essentials of what is absolutely necessary to safely dive is a very small set of skills and knowledge. They can indeed be taught by rote.

I think your definintion of safety must be different than mine. You are correct that throwing a dive rig on and hitting the water takes a relatively small skill set. I am sure that you could train a monkey to do it. In fact, I bet you could also train the monkey to respond to the different beeps coming from his dive computer.

To me, diving safely means understanding what your dive computer is telling you and then treating it like you would a girlfriend that you caught cheating on you. You might trust her again, but it won't be without a healthy dose of skepticism. That skepticism stems from education, not training.

 

[Dragon2115]

Sounds to me like some people are ok with building the house without first building the foundation.

Charlie99, I think you exagerate when you start talking about using log tables etc instead of a calculator. The thing is you know about log tables. You don't like using them, but you know how if you had to. Nobody is saying a nitrox student has to be able to derive the gas laws. This is much more basic. This would be more compareable to teaching someone addition by showing them how to push the "4" key followed by the "+", the "4", and finally the "=" key on a calculator rather than teaching them that 4+4=8. In the end all you have is a button pusher that has no understanding of what addition actually is. If the calculator breaks they're done. They have no idea of what to do. All they know is what buttons to push.

As I said in my earlier post, if I punch 5x5= into my calculator and it gives me an answer of 32 I know something went wrong. The people that only know how to push the buttons don't. We've done this in schools all over the country and it's why we have to have cash registers at McDonalds with pictures of the product instead of numbers and why if the cash register doesn't tell them the correct change they have a hard time figuring it out on their own. As a result of this, how many people do we have running around that can't even handle the basic skill of counting back change? Do we really need to perpetuate this in diving too?

What I find interesting here is that a lot of people get very upset about how the OW courses are being dumbed down to the point they are producing what are essentially unqualified divers, yet at the same time have no problem with the same thing happening to other classes. I just don't get it.

 

[Soggy]

And the sanity injection award goes to....

Uncle Ricky!



Yes, this is all any of us closed minded, egocentric people have been trying to say. Uncle Ricky said it a much more succinctly and elegantly than I did.

C'mon, gang, let's inject a little reason in here. All Soggy (and I) have been touting is that knowing the math, knowing what's reasonable and what isn't reasonable, based on current deco theory, is necessary to be able to tell if a computer is lying to you or not. We think that's important because computers do lie from time to time, and you can get in trouble if you don't know enough to catch it when it happens.
The other point he (and I) has is that you cannot depend on computers to warn you when you're exceeding some limit by alarms, because (1) by the time the computer alarms the event is in the past, and/or (2) you may not hear or see the alarm. It is therefore incumbant upon the prudent diver to have enough situational awareness that the alarms become superflous, at most a simple confirmation of what the diver already knows.
As for conservatism, I often dive a SUUNTO and an Oceanic side-by-side; the Oceanic makes the SUUNTO look like a paranoid nanny. Which one's "right?"
Me, I stick with what I know is reasonable from my own math and tables calculations and make sure I don't exceed that; the computers are backup.
Rick

 

[DivesWithTurtles]

C'mon, gang, let's inject a little reason in here. All Soggy (and I) have been touting is that knowing the math, knowing what's reasonable and what isn't reasonable, based on current deco theory, is necessary to be able to tell if a computer is lying to you or not. We think that's important because computers do lie from time to time, and you can get in trouble if you don't know enough to catch it when it happens.
...

Anyone here propose teaching Ratio Deco or another seat-of-the-pants method to OW students? Anyone here propose teaching Ratio Deco or another seat-of-the-pants method to us here on the internet? Using tables is notoriously fraught with user error. Surely that is not an adequate method for a sanity check on what the computer is telling us.

 

[Soggy]

Anyone here propose teaching Ratio Deco or another seat-of-the-pants method to OW students?

No, OW students aren't doing staged decompression dives, thus have no need for ratio deco.

Anyone here propose teaching Ratio Deco or another seat-of-the-pants method to us here on the internet?

Go over to the 5thd-x forums and read about it yourself, or PM someone that knows how it works. If you get yourself bent, it is no one's fault but your own, though.

Using tables is notoriously fraught with user error. Surely that is not an adequate method for a sanity check on what the computer is telling us.

Man, are tables really that hard? I guess I don't understand. Find depth column...find time column...blamo, magic number. Doing the whole pressure group thing and RNT doesn't seem that challenging to me either. It's sure a lot easier than "PLAN PLAN PLAN DIVE SELECT DIVE PLAN PLAN SELECT SELECT SELECT" or whatever combination you have to go through to get into the right planning mode on a computer.