Bent. I guess it really can happen to me.

[Crass3000]

Not trying to be an ass and I'm sure it has already said but why such a short surface interval. I've always been taught to take at least an hour surface interval and that's what I stick to. Sounds like you're more experienced than me so I'm not calling what you did dumb but maybe make sure your surface intervals are more lengthy in the future. It can make a big difference.

 

[TechDeep]

It has been pointed out to me that I may have been a bit harsh in my earlier reply. And to a point I see where that is true. But to explain my mindset a bit, I had just finished teaching an SDI wreck class with limited penetration at a popular training site in my area. During the weekend we were there and I was drilling into my student's head to plan, plan, plan, and plan again and never trust a computer, Divemaster, or Instructor to keep you safe, we saw repeated things that sent chills up my spine. In addition to the wreck training he got a good lesson in how easy it would be for someone to put themselves in a position to get hurt and have no idea that they were doing it.

The worst part was when the people pulling these stunts were obviously, from the way they were interracting with what were clearly new OW students, "dive professionals". So when a dive pro posts about what I specifically warm my students not to do - flying the computer - on top of what I just witnessed, it has the tendency to remove some of the tact filtering software in my brain.

I stand behind what I said 100%. No apologies for that. What I do apologize for is the way it was said and the "deserved hit" remark. That was out of line.

No sweat Jim, your intentions were admirable, and message received, loud and clear. You've obviously dedicated your life's work to training safe divers, and I respect that. The medical director of the chamber where I took my ride was off for the Labor Day weekend, but he called me on Tuesday for a chat. It was almost like he was reading your post to me, except you hadn't posted it yet.

Even though this was strictly a pleasure dive, the guys working on the boat know me well, and have no problem with me "assisting" other divers. Believe it or not, one thing that bothers me a lot about dive training is the fact that we give out a C card, and that's it, they are good to go. In my opinion, this fosters a real world tendency to let the "formalities" fall as time goes on. Every time I'm on a boat I see it. Instabuddies get teamed up, and off they go.

I was caught doing the same thing, without really realizing it. The guy who is always yelling BWRAF, or Bruce Willis Ruins Action Films was in trouble due to his own complacency and inattention to detail. One thing that never ceases to amaze me....every time the divemaster asked if everyone had a timing device, it seemed like just about every time, there was at least one diver who didn't even have that.

Anyway, as wake up calls go, this one was pretty good. I will be making some changes to be sure, especially on "shallow" or "routine" dives. Thanks.

---------- Post added September 6th, 2013 at 06:23 PM ----------

I think the terms "deserved" and "underserved" in regards to DCS does a disservice to anyone trying to understand tables, computers, algorithms, and DCS in general.

The only way to ensure not getting bent is to not dive. Period. Everything past that is a game of probability. Even if you follow the tables to the letter, you still have a nonzero chance of getting bent. Its the name of the game. It can happen to anyone, and if you dive long enough, its probably going to happen to you.

+1, couldn't agree more.

 

[Tigerman]

The DSAT (PADI) tables have intervals down to pretty much 0 - you can do less than an hour, but youre penalized with regards to bottomn time, especially when diving air. The profiles of the OP however was not bad even with a shorter SI..

 

[drrich2]

So when a dive pro posts about what I specifically warm my students not to do - flying the computer -

So, if a person were 'flying the tables' (basically, pushing but not exceeding NDLs), is that really so much better?

If a person gets his NDL limit sitting on a boat looking at a table in advance, or dynamically via computer calculating an algorithm during a dive, either way he's getting a limit from a device and not exceeding it.

After that, you can always claim 'more conservatism would've prevented this.' Maybe diving a Suunto, known for a conservative algorithm. Maybe using tables. Maybe waiting longer between dives. Or just staying on the boat. It's no clear distinction where to draw the 'It's your fault' line.

...sometimes S**t happens.

That it does.

Richard.

 

[Ken Kurtis]

As it was explained to me,some 9-10 years ago, "expected/unexpected" and "explained (explainable??)/ unexplained (unexplainable)

I've always used (and been fond of) "predicted/unpredicted". I've never liked deserved/underserved. Too much stigma.

- Ken

 

[tkdgodess]

4 divers, same gas, 2 pairs same age. 1 woman, 3 men. Exact same profile. Vpm+3 plan executed, plus 4 multigas computers ticking away in the background, all cleared. One diver bent. Imo contributing factor to the bends for the one diver was lack of hydration, lack of sleep and lifestyle stress. Older man got the hit. So was it underserved or deserved? Conservative plan cleared, plus computers cleared. Diver has dove again, and no bends. But i made him a custom water bottle, and no more deco when tired or stressed. Theory.

 

[Tigerman]

I've always used (and been fond of) "predicted/unpredicted". I've never liked deserved/underserved. Too much stigma.

- Ken

And really, what kind of a douche do you have to actually be to DESERVE getting bent? I cant think if many ordinary people I would wish it upon..

 

[dumpsterDiver]

It's been several months since I watched this. I'll have to go back and see what you're talking about.

Hint: Look at the slide at 7 minutes....

 

[beaverdivers]

The way I interpret the manual, you can only adjust the Gradient Factor when using closed circuit mode. One thing I can tell you for sure is that with this computer in REC mode, there is no adjustment of the algorithm available whatsoever. Not even a setting for different levels of conservativeness. Never bothered me much before, but now I wish I had a way to set it more conservative for me.

FYI, there are dive computers that allow you to set up to 5 levels of conservatism. The Uwatec ( Scubapro ) dive computers use the ZH-L8 ADT MB algorithm that has a worldwide proven safety record. This enhanced algorithm allows the user to choose which micro-bubble level thus enabling the diver to reduce the risk of the bends.

 

[ianr33]

FYI, there are dive computers that allow you to set up to 5 levels of conservatism.

FYI there are computers that allow many more levels of conservatism than that. Shearwaters for example let you change both High and Low gradient factors independently. Dunno how many combinations that is,but it's a lot more than 5.