Have you gotten bent?

[Luxrok]

My first hit was in open water after hanging onto an anchor line for 45 minutes in moderate seas. I don't remember switching arms. I had pain in my right elbow. Took some O2 on board the boat, skip the second dive and the pain resolved. However, since then I get niggles there.

On two occasions, I have had very sharp pain in both my elbows when doffing my CCR in the water after long 290ft cave dives. The pain goes away instantaneously or very quickly. Not sure if that is a bend or not. I have since found a way to remove my CCR in a more graceful way to avoid those pains.

I also had an occasion that I had some swelling in my chest muscles and some discoloration/molting after free diving the day after a deep dive. My dive buddies convinced me to go to the chamber because they thought I was bent. The diving doc told me it was sun burn and sent me home. There are many jokes about that now.

Hans

[rchrds]

Wow- I thought I was posting in this thread, but was in the other thread. Here is my rather in depth description of my bends, some friends bends, and some opinions. (Long.)

http://www.cavediver.net/forum/showp...6&postcount=15

Jason

[txdiver]

And again we are hammering Ratio Deco... The only time I took a good hit was with a tx computer and no - it was not deserved and no - I don't have a PFO.

Ever since I dive RD I had no such problems but I always find it interesting that people try to attack RD but in most cases truly have no clue about it. This includes some very prominent members of this country's diving elite. However, when challenged, they often and quickly admit that they may have misspoken and really don't know much about it. I don't know if Sluedge falls into this category but I suspect he does. Anyone that has somewhat solid knowledge of Ratio Deco would never make a statement like this. Furthermore, the lack of knowledge is evidenced by the fact that the earlier poster implies that RD is a radical decompression theory and not an application of widely accepted decompression methodologies as they can be found in your tx dive computer or in any commercially available dive planning software.

I find it sad that ignorant statements like that still find a public outlet. Divers that use the RD approach are not posting that everybody else who is not diving their way is "on the express way to hell" (true quote before retracting it).

I really would hate to see Andrew's post getting derailed by this. I will not engage in a s...-throwing match but if you want to you can pm me.

[rchrds]

I think you could just have discounted his post as "hey, he probably doesn't do dives that require that level of decompression planning, and is happy doing what he does, so...skip to next post" rather than taking it personally as an affront to the method of deco that you choose to advocate. Nobody else took it personally, and those that are interested will find the details on "ratio deco" rather than discounting it due Sludge's opinions.
...skip to next post...

[Sludge]

I've read extensively on Ratio Deco and there's nothing wrong with the math behind it. Where I find a problem is it's up to the diver to decide on the fly how deep he was for how long. That's where human error can appear.

[fitnessdiver]

I listed mine as a mild type one....

Did a cold water dive to 365ffw and on deco had a reg malfunction so needed to switch it out to another reg. Later while engaging in full contact deco I ripped the thumb off my glove and my hand flooded and water seeped into my suit up to the shoulder. After the dive my shoulder was itchy and a buddy said the skin was blotchy.

Did nothing for it --actually forgot about it since the itch didn't last long, and the following day did the same dive again with no side effects.

So not sure it really even was a hit, but I'll call it one to be conservative.

[aainslie]

Russell, I suspect that RD or tables aren't the culprit. Certainly I had one of mine using an X1 on +4 and a Vision on 15/85, very conservative settings. Didn't surface early. Go figure. Another was when I was hurrying in Cow - I usually hang out at about 40-50 in the vertical bit for a few minutes but I had someone waiting for me on the surface and my computer was clear to 20 ft so through i went... and got a skin bend immediately on surfacing.

[Sludge]

Russell, I suspect that RD or tables aren't the culprit.

I guess I didn't say what I meant. I don't think either ratio deco or tables are the culprit, either. Human error is the culprit.

This section bewilders me. I don't think I could ever trust myself to do this, and I'm a math guy. Not when it's MY health on the line.

Depth Averaging

The easiest way is to break bottom part of the dive into 5 min segments. Average each 5 min segment. Take the deepest segment and the shallowest segment and add them together. Divide by 2. This will give an average for the dive. Now weight it for depth and time. Meaning if you spent more time deeper then weight towards that depth. If you
spent more time shallower, then weight towards shallower.

Example: Dive on 21/35 using nitrox 50 for deco and the dive profile is 100’/30m for 5min then 150’/45m for 5 min then 160’/48m for 5 min then 140’/42m for 5min then 130’/39m for 5 min then 100’/30m for 5 min. Total 30 minutes you would do this:

So deepest is 160’/48m + shallowest 100’/30m = total of 260’/78m divide this by 2 to equal 130’/39m. About half the dive was spent shallower than this, and the other half at this depth or deeper, so we can use this average without adjusting to weight for depth. Using the average of 130’/39m, the deco would be 20min on nitrox 50 for a 30min bottom time.

A conservative approach to weighting is to average each of the bottom time segments pair wise, starting with the shallowest. In detail, find an average depth for each 5 min segment. Then, sum the depths of first two shallowest segments and divide by 2. Then use that average and sum it with the depth of next deepest segment and divide by two.

[aainslie]

Yeah, Iv'e always thought that any procedure based on doing arithmetic while underwater is a little... err... hokey.

But that's a whole different story. I'm amazed at how this poll is going - 1/2 of us roughly have had hits! More than 5% have had serious incidents! That's incredible.

[FW]

But that's a whole different story. I'm amazed at how this poll is going - 1/2 of us roughly have had hits! More than 5% have had serious incidents! That's incredible.

It just shows what the Navy has been saying for years, the tables (algorithms, etc.) are based on averages. There is no guarantee that you won't get bent, even if you follow the tables, computer, underwater math, etc.