Computers & DIR

[JeffG]

It was covered in both my DIR-F classes

Also in my two. First time it was the Big Woooooooosh, because it was covered very quickly. But there were good reasons for that. We had other issues to deal with first before giving up the computer. The second time through, it made sense. (Both times were with AG)

 

[Scuba_Steve]

Not in mine, which means it must be "optional",....sorry I only took one class.... LOL BWaaHHHH. LOL

Nice NEW avatar Jeff. You are one bent puppy.

 

[kalvyn]

well, i took DIR-F and this wasn't covered, so no, not all of them

It was not covered in my DIR-F either, and I took it before it became a pass/fail class. I and a couple others did ask about it, and the paraphrased response was "take Tech-1". The concept of depth averaging and the 120 rule was briefely mentioned, though.

Jimmie

 

[Derek S]

It was not covered in my first class, but it was in my 2nd.

 

[detroit diver]

Well, if you had a decent instructor like AG, things might have been different.....

my DIR-F had J.J. and David Rhea (sp?) present, and nothing was mentioned
by the instructors (who were being observed) or as comments by either J.J.
or David Rhea.

i figured it was an advanced thing, mostly to do with deco

 

[H2Andy]

Well, if you had a decent instructor like AG, things might have been different.....

lol i loved my instructors.

i think they were too busy trying to keep us from killing ourselves with bad
bouyancy to worry about such petty things as computers

 

[waynne fowler]

well, i took DIR-F and this wasn't covered, so no, not all of them

It was covered in depth in mine, we were also shown MDL's and how to apply them to repetative dives. Depth averaging I learned at a later date. Perhaps there were other issues to deal with leaving no time to cover this. However your Fundamentals of Diving book covers it.. not in the depth that my Fundi's class did but it does point to GUE's thoughts about computer use.
I have since set through 2 other Fundi's class' and in both of these they had the same coverage of this issue as I recieved.

For the average OW diver... if you have a computer use it if you wish. But make sure that you are using your head at the same time. Learn about MDL's and how to incorperate proper ascent stratagies into your diving. This is especially true of divers that have been exposed to the concept that there is this whole concept of "Diving without a computer running your plan".
For those, you will find that your comfort & confidence level will probably increase noticably as you will now be able to pull off a proper profile even if your computer takes a dump in the middle of your dive. Neither will you have to quit diving for the day if it happens.
For those that are oblivious to this concept there will most likely be, in the back of their brains, this little nagging voice that they will hear once in a while "what if my computer craps out"? Of course they will probably do as they have been taught "make a slow ascent to 15' hang out for 3 - 5mins" and then stay out of the water for 24 hours, and then dive tables.
Most probably nothing bad will happen, most of us dove this way for many years. Is it optimum.. IMO.. no... Is there a better way... IMO.. yes... Do you increase your odd's of being bent.. IMO... debatable... One thing I will say for a computer is that it gives the new diver a great method to keep the ascent rate in check.. not that there are not other devices that will do this... and at a lesser cost then a computer..

OK now I'm rambling.. I gotta get back to work.... YUCK!

Just some of my thoughts on the subject.... YMMV

 

[H2Andy]

For those that are oblivious to this concept there will most likely be, in the back of their brains, this little nagging voice that they will hear once in a while "what if my computer craps out"?

well, of course you follow your backup dive plan. which is why i carry a watch
and tables with me on every dive...

until you find a better way of doing it, which is what my question was designed
to do...

where do i find out, other than the fundies books (and J.J.'s books), which cover
the subject in abysmal paucity, the real nuts and bolts of diving without a computer?

i guess i'll have to take DIR-F again, since my class didn't cover this
important aspect. and personally, i am not willing to let go of the computer
without one-on-one instruction on the subject, real-time.

the process sounds very simple, but i want to make sure i learn it right.

also, is computer failure really that much of a worry? doesn't DIR teach us
to disregard "fake" failure points and concentrate on real ones?

to me, a computer is much less a failure point than a single first stage, and
yet DIR does not prohibit diving with a single first stage.

 

[MHK]

This has been an interesting thread for a variety of reasons. Let me offer a few thoughts for consideration:

1) Several of you are missing the larger picture and are searching for absolutes in a world complete with THEORETICAL complexities;

2) All DIR-F classes are not created equal, meaning that some instructors include certain information in their classes, and other instructors don't. GUE, unlike other agencies, actually encourage their instructors to exceed minimum standards, so while all DIR-F classes will include required discussion points, some DIR-F classes may actually exceed the requirements. It's a decision available to each instructor, and at our discrestion we may choose to add discussions respecting "on the fly" NDL computations, and the like;

3) Lastly, I'd like to encourage everyone that has contributed to this thread to bear in mind that part of accepting some of the DIR concepts requires a willingness to keep an open mind about certain things. That isn't to suggest that we squeelch dissenting points of view. In fact, just the opposite, we welcome an exchange of ideas based upon the merits of the respective ideas. That said, many divers are trained in the OW classes to respect a set of tables that provides for a time certain at a specific depth, ie; 20 minutes @ 100'. Very early in a divers career they are taught a concept that varies with our approach. As a result of that early pavlovian-dog-like approach, many divers are reluctant, unwilling, or unable to consider that decompression theory isn't that exact of a science, and that providing a time certain for a specific depth is simply a decompression modeler's way of giving a diver information that correlates to the shape of the ascent rate curve that the modeler desires within his specific algorithim. In other words, the 20 minutes isn't necessarily the "absolute" inasmuch as it provides for the ascent rate starting point. M-values vary from diver to diver, from day to day, so the "limits" that many are fixating on merely predict with reasonably certainty a shape that has proven over time to be reliable in terms of ascending without experiencing signs or symptoms of DCS. Just like you can't credibly defend 20 minutes @ 100' as an "absolute", you simply can't credibly defend the methodology that we advocate as an "absolute". The underlying component to bear in mind that is dispositive of the issue is that we are discussing "theoretical" issues that contain a wide variety of variables, so searching for a mythical certainty will prove to be an elusive concept.

It's best to understand as much of the subject matter as you can, and we believe once you do that, you will conclude that dependency on in-water devices such as computers isn't as necessary as some would have you believe, nor is it as difficult to track NDL's in the absence of an in-water computer as some would have you believe.

Hope that helps.

Regards

 

[kalvyn]

and personally, i am not willing to let go of the computer
without one-on-one instruction on the subject, real-time.

And you're a wise man for doing just that, in my opinion. Learning how to dive over the Internet is never a wise idea.

In my fundies class, Sonya said that for recreational dives if you dive a computer to continue to do so. Just start working the stuff learned in the class into the dives; the stops at 30, 20 and 10 for example. I still dive my Mosquito, and I still do a "safety stop" as far as it's concerend. I'm just not doing the stop at 15' fsw for 3 minutes.

I also routinely forget to put the darned thing into EAN32 mode, so I "bend myself" on a regular basis according to my computer. I just ignore the thing, though I always burn off all accumulated "deco" in the shallows.

I do dive bottom timer only in the tropics though. I have a D3 and my wife has a Hyper AquaLand. I do the depth averaging thing and the 120 rule, and do just fine. I usually carry my Mosquito in one of my pockets, and I'm getting out of the water just fine, according to it.

Jimmie