DIRF, A Sobering Experience

[jbd]

I have read somewhere(I can't remember where) that initially the acsent rates were 30 FPM. However Navy divers complained that this was too slow and asked for 100 FPM. In the end 60 FPM was selected as a compromise. This was still working on the bend 'em deep cure shallow theory. I wish I could provide the source.

 

[trheeltek]

Originally posted by detroit diver


The current PADI standard is garbage. Just about every expert in the field agrees on a max 30 fpm ascent, and slower if possible.

Ever notice how tired some people are after getting back from a dive? They're bent. Not the crippling kind, but bent nonetheless.

I'm well aware of, and practice, the current thinking on ascents. Again, I'm not encouraging people to ascend at 60 ft/min. I'm simply pointing out that empirically, millions of successful dives have been safely done using the current PADI standard. In the example we're discussing, we can empirically expect a similar safe result, which makes it a fun problem to argue about. But, I wouldn't do it, and neither should anybody else.

Moving on though, you raise an interesting question, one I've always been curious about - when is a diver bent? I mean, we all surface still offgassing and do surface decompression. While we're not so saturated that we notice anything, I assume that the dissolved nitrogen nevertheless triggers some physiological response - we certainly have microbubbles floating around in there, so N has come out of solution. So, what's the line in the sand - are we officially bent only if the symptoms are noticeable (i.e. fatigue, skin bends, crippling neurological DCS)? Obviously if you come up with joint pain and take a chamber ride, you're bent, but what if you feel tired but can safely offgas at surface, are you bent in any important way? I learned an important lesson in deep air - every dive is a decompression dive. The corollary to that might be, you get bent on every dive. Just not enough to notice. Anyway, just something to pass the time with on long boat rides.

 

[detroit diver]

I guess your question goes to the crux of the issue. When are we bent? My feeling is that if you're fitigued, you're bent. Even without pain symptoms. And seeing as though we don't know the long term consequences of "fatigue bends" or similar, I don't want to experience them. That's why I follow so closely the GUE standards that this thread was originally about. It's not about just equipment, it's a mind-set. Get bent and fix it-that does'nt cut it with me. My theory (FWIW) is-if a big bubble can double you over, kill you, or cripple you for life, the little bubble can't be anything positive.

I know when I do the one minute stops every 10 feet instead of the 3 min@15 feet, I feel better-especially after the longer dives.

 

[Lost Yooper]

Originally posted by TwoBitTxn
If DIRF isn't a carded class why do you consider it pass/fail. You enter the class with the intent of learning something. If you learn something you did what you set out to do. I don't see how you can fail this course, or pass it for that matter. If you "pass" it then you have shown you are ready and have the skills to go on to the next class. Thats great. So very few people are able to correct their defficiencies from years of bad habits developed thru poor training in a weekend. Are you suprised?

We are so quick to label someone a failure when they don't measure up when it should be a case of hey this is what you need to work on to bring your skills up to the level they need to be to take the next step.

TwoBit

I hold myself to pretty high standards, so I tend to view things as failures and accomplishments for myself. You are right that there is no way that that three or four dives will correct years of bad habits. This is why DIRF is not a pass/fail class. I was harder on myself than I should have been, which isn't uncommon. Now that I've had a week to relax, I feel much better.

posted by Cave Diver.

I am very much a 'show me why' kinda guy. I don't do something because the crowd does it, I do it because it makes sense to me. And DIR makes a lot of sense. So much so that I have been dragging a few other divers along, kicking and screaming in my quest for knowledge.

The big turnoff that I had from *SOME* DIR guys initially was the "we dive this way because we are the best, so you should to." That's fine, and they may well BE the best, but that doesnt solve my need to know WHY something is a certain way.

It is very refreshing to see how some of you guys (and gals) that are more evolved than the rest of us take the time to explain the how, the why and to give us the cold hard fact that in some areas you just didnt measure up.

Many of you on here have earned a great deal of respect from me just based on knowledgeable answers, even tho I have never seen you dive. I suspect that quite a few of you have skills that are much better than mine and to read a report such as yours give me that much more pause to stop and reconsider how *good* a diver I really am. Everytime I dive with someone I mentally measure myself against them. Some have better skills than I. Most do not. But everything that I read from you guys goes towards making me a better diver and I for one thank you for that.

BTW... Been meaning to ask... What exactly *IS* a Yooper anyway, and how does it go about becoming lost?

All throughout the class, the instructors asked us to challenge them regarding the why’s of DIR. As I recall, not too many tried. I suspect most of the students had already been convinced through research and experience that DIR makes perfect sense. The questions that were asked were easily answered in a thoughtful and understandable way. I never heard an instructor say “because we say so, that’s why”, which we hear so much of on the net. Every last detail of DIR is well thought out and has a clear-cut reason behind it. Seeing it in action, or experiencing it yourself is the easiest way to see the advantages. I found it to be particularly impressive just to watch the instructors use DIR in it’s most efficient form.

What’s a Yooper? I grew up in the Upper Peninsula (or the UP) of Michigan. Residents of the UP are referred to as Yoopers. Now, the Mackinaw Bridge connects the UP to the Lower Peninsula. Yoopers call those who live under the bridge trolls. As for my being “Lost”, well, in my case, “lost” may refer to a range of different meanings. It may be taken quite literally from time to time , or more metaphorically (depending on my mental state ). For the time being, I’m living in the LP, which would technically make me a troll, but I won’t succumb to such humility. I’m a Yooper at heart who just happens to be lost. .

Mike

 

[MikeFerrara]

detroit diver,
What do you consider a longer dive? I don't think that for a reasonable series of "average" recreational dives that include a 3 min stop at 15 feet and a slow ascent that you should feel bad. As decompression stress increases so does the importance of efficient deco. The first step as I see it is to minimize the stress by useing the right gasses and diving sensible profiles. One of the criteria we have placed on "recreational diving" is that a direct ascent to the surface is possible. If you consider the 1 min at 40, 30, 20, 10 as manditory then you have a vertual overhead and should be planning gas based on the rule of thirds.

 

[Blargh]

Originally posted by detroit diver
I guess your question goes to the crux of the issue. When are we bent?

Whenever one feels like been beaten with a big stick. Or even a medium-ish stick.

My feeling is that if you're fitigued, you're bent. Even without pain symptoms. And seeing as though we don't know the long term consequences of "fatigue bends" or similar, I don't want to experience them.

No, but creeping osteonecrosis is always a possibility... :/

That's why I follow so closely the GUE standards that this thread was originally about. It's not about just equipment, it's a mind-set. Get bent and fix it-that does'nt cut it with me. My theory (FWIW) is-if a big bubble can double you over, kill you, or cripple you for life, the little bubble can't be anything positive.

I know when I do the one minute stops every 10 feet instead of the 3 min@15 feet, I feel better-especially after the longer dives.

 

[Tavi]

from your report:
" but we did get to compare packages… drysuits and undergarments, that is. By starting with the undergarments, we were able to determine the range of motion ours would allow for valve drills. Andrew went around the group and pointed out the pros and cons of the mfg's and even between models from the same mfg. "

So which Drysuits and undies are preffered??

To all,

With your harnesses adjusted tighter, are you able to easily get in and out of your harness???

 

[detroit diver]

Tavi,

The drysuit underwear that was the most flexible was made by Ocean ? (can't remember the last name!). It had a very flexible fabric on the outside-stretched in every direction. I was very impressed with it.

As for drysuits, he didn't like a lot of them. Most problems were with a seam that went up the arm inseam. It doesn't allow for full arm extension. Also, the torso recoil system (like in my Bare) sounds good on paper, but once you've got all of your stuff on, it doesn't move at all.

Maybe one of the other participants can remember specific drysuit suggestions.

With the harness tightened, it does make it a little more difficult to don and doff, but the diveability is so far enhanced that you don't care! My whole rig was shifting around before my adjustment and now it actually feels good.

 

[Tavi]

Originally posted by detroit diver
Tavi........

........With the harness tightened, it does make it a little more difficult to don and doff, but the diveability is so far enhanced that you don't care! My whole rig was shifting around before my adjustment and now it actually feels good.

I had it to where it felt great diving, But I had a hell of a time getting in and out of it (mostly out). I figured it couldn't be right (your supposed to be able to doff and don right?) I loosened it back up.
I liked it better tight.

Thanks,

 

[detroit diver]

Ah ha! I just remembered the name of that drysuit underwear-

it's Ocean Concepts.

Takes me a while......