Nitrox Class Without Tables or Math...OK?

[DivesWithTurtles]

...

Rather than hijack this thread further, I've started a new thread. Rick, your answer is pertinent to that thread. I hope you'll post in that also.

 

[MikeFerrara]

And you teach this to your students??? I am not sure I would want the liability! As I said: you got me beat! No tables and no narcosis! I am impressed! Is the next thing to go your regulator???

Do I teach it to students? Students use tables or computers as required by traing standards so the liability is covered and the insurance company is happy.

What I do (or did) is show students is the large variation between different tables, computer outputs and software outputs for the same dive and why. They see, for instance, that even though a PADI table will let you do a 130 ft dive for 10 minutes with a 3 minute safety stop at 15 ft, that my software doesn't like it, and I'd plan a 130 ft 10 minute dive FAR differently and the same goes for many computer profiles.

The purpose of what I do present is to get them to put table NDL's and computer outputs in perspective and not to be to trusting of them. Also to pay attention to other important aspects like slow very controlled ascents and physical condition which really aren't stressed much in the text. You might consider it a brief elaboration on what the book does say about undesireable profiles and not redlining the table or computer.

Too much info? The brief statments in the text might be adequate if they sunk right in. However, this is one of many little elaborations that I added to address specific concerns with how I saw (or heard of) my students diving after being certified. How many of them took their brand new c-cards to Cozumel (or some place) and promptly followed a DM on dives that pushed their computer and left them with barely enough gas for a safety stop and often times without. The "It's fine. We do it all the time" statments at resorts (even from pros) too often had them doing things that they just hadn't really considered very well. Too many times I found myself having these conversations with students AFTER their vacation and I decided that it was a conversation best had before the vacation.

There are other elaborations that I added like showing the "A deceptively easy way to die" video to EVERY class. Why? Because too many times I had students come back from vacation and relate horror stories to me about trips into wrecks at 90 ft beyond the lighted zone in a group following a DM where the DM was the only one with a light. ok divers do this stuff and I can't stop it but I did figure that I could give them a few things to think about before they did it though.

But...what's with the cocky no narcosis comment? Diving on my end of the country is governed and limited by the same physical laws as it is on your side of the country. Did I write something to make you believe otherwise? I just don't think that computer alarms are at all a reliable way of dealing with problems or mistakes that might arise due to narcosis.

But for my own diving, I don't need to carry tables or a dive computer...not to be confused with not using decompression models...and the post you reference was concerning my own diving.

 

[Rick Murchison]

I just don't think that computer alarms are at all a reliable way of dealing with problems or mistakes that might arise due to narcosis

Computer alarms are totally worthless for those of us - and there are many - who can't hear 'em anyway
Rick

 

[MikeFerrara]

Computer alarms are totally worthless for those of us - and there are many - who can't hear 'em anyway
Rick

I can sometimes hear them if I don't have a hood on. Sometimes when there are computer totin divers around I hear the little beeps everywhere...usually when they are ascending but I notice that the beeps don't change anything.

When I have a hood on, which is most of the time, I can rarely hear them. Many times after a dive divers would be discussing some ones alarm that was continuously going off and in most cases I never heard it.

 

[The Chairman]

Mike, you have stated at least twice that you teach your students how to not get narc'ed. That's beyond my abilities. Me? I teach them that narcosis starts a lot earlier than you think, that you normally can't feel it and that you should AVOID it as much as possible. The most dangerous diver is the one who says that they never get narc'ed.

As for the tables... do as I teach, but not as I dive? That's a slippery slope, though there are things that I teach that I do not do (like have a buddy on every dive). For the most part, I try to dive in the way that I teach: less ambiguity that way. But why in a discussion about a dive class do you feel it neccesary to bring up how YOU dive without the need of tables or computers? It sounds as if your opinion of your diving prowess far exceeds mine. You thus present yourself as being above these "ordinary laws" of the mere mortal and it smacks of arrogance. Humility is a good thing in my book. I personally need more of it as do most people! It is my humble opinion that arrogance can kill a person faster than anything. Especially if it's combined with a healthy dose of denied narcosis.

I give instruction on a focused area, and try to do that exceedingly well. I refrain from trying to cure every bad habit they have in one class. One step at a time. Safety is always first. If you want the next step, take the next class, or just go dive with me. I don't keep many secrets.

 

[The Chairman]

Many times after a dive divers would be discussing some ones alarm that was continuously going off and in most cases I never heard it.

I try to teach situational awareness... that includes checking guages, listening to alarms as well as good buddy awareness. It's like not noticing the check engine light on your car because no one ever taught you to look.

However, that's part of my OW class. It's not in the scope of this class.

 

[Scuba_Steve]

C'mon Pete, stop with the BS. You're better than that.

You know darn well what Mike means with respect to narcosis.

The same thing for the comment

As for the tables... do as I teach, but not as I dive?

You know damn well students need bits of info at a time as their diving progresses. Mike teaches a more appropriate "ascent profile" and he's smart enough to kow how to run dives. He teaches a lot of the basic understanding up front, knowing full that the students need to get used to all of this. Also as we all know, our respective agency's would look pretty sideways at us if we just up and taught how to run a proper profile as we see it, righ toff the bat. We need to cover our *****e$ even though we do not neccessarily agree with what is being taught.

IE: If my computer (the one I don't use) died on me during a dive, tehre's no way in hell I'd sit out 24hrs before hitting the water again. Well, that's what I have to teach now don't I. I personally prefer to use my head an realize I just looked at the time not 2 minutes ago more than likely, so I can make a reasonable assumption and get on with it.

IE I had to state that descending feet first is the desired descent procedure for my AOW class the other day. Well, I think it's BS, and I said so. I then cover my butt by stating if you can't control your descent as you should be able to, then I guess I would in fact descend feet first so I could kick up preventing an impending ear implosion when I also couldn't clear my ears.

Of course this entirely back-aswards approach is standard fare in rec training.

Our options are to not teach, or to teach what we know to be best, knowing we aren't a poster child in our respective agency's eyes.

Pete, you know this is the deal. Yes it is a slippery slope, but I think it's worth it.

 

[Soggy]

I try to teach situational awareness... that includes checking guages, listening to alarms as well as good buddy awareness. It's like not noticing the check engine light on your car because no one ever taught you to look.

Listening to alarms is the antithesis of situational awareness. It is a complete lack of situational awareness that causes those alarms to go off. It is not analogous to a check engine light because that light can indicate something is wrong in a place that is invisible to the driver whereas with diving, depth, time, and gas mixture are the only variables that are calculated into an alarm: all of which are visible to the diver well before the alarm goes off. The only time I ever had an alarm go off was when my stupid vyper, in computer mode, didn't know how to calculate MODs accurately and started screaming at me 4 ft *above* my actual MOD, even though I had told it to use a 1.4 PO2.

Holy runon sentence, eh?

 

[Rick Murchison]

Listening to alarms is the antithesis of situational awareness

Bingo! Soggy wins the prize!
Rick

 

[H2Andy]

Holy runon sentence, eh?

no, actually ... all were nice sentences, with this exception:

It is not analogous to a check engine light because that light can indicate something is wrong in a place that is invisible to the driver whereas with diving, depth, time, and gas mixture are the only variables that are calculated into an alarm: all of which are visible to the diver well before the alarm goes off.

a minor error, but properly, you should have a comma, not a colon, to separate
that last dependent clause.

if you want extra emphasis, a dash "--" would work too.