Uwatec problems

[matt t.]

Jon,
I will definitely try the stops every 10 feet next time we get out. Usually after 2 dives (on the Willie for example) I go home and crash for the rest of the day. I feel like I've been up for 3 days. I wonder how much Nitrox would help with that in conjunction with the deeper stops? Would it be that much more noticeable?

Matt

[Omicron]

Nitrox does help you feel a little bit better after the dives - not quite as worn out.

I know what you mean about diving and being tired - I always crash on the way home after diving if I'm not driving

[Colin]

Actually, the comment regarding none of the current computers using the deep stop theory made by FreediveWi isn't quite right.

In fact, Uwatec in their "Smart" series of computers, uses a system of "level stops" which can help with the reduction of microbubble formation. These stops are not mandatory, just precautionary, similar to the stops that some of the members mentioned they do.
This is because the effects of microbubble formation are largely a long-term condition, and a precursor to DCS. The biggest part of this type of algorithm really addresses the diver who does a lot of diving in a day. The computer will assess the likelihood of microbubble formation based on the previous dive profiles and recommends an advisory deep stop to be completed upon ascent.

A simliar algorithm exists some of the Suunto computers. They call it the "RGBM Model" and allows the diver to select the level of "conservancy" for succeeding dives.

The important part is that technology is only as good (competent) as the person using it.

Colin.

[FreediveWI]

I've used the Sunnto computers that are supposed to be programmed with the RGBM model and it is NOT the same as a true deep stop deco table. I now just switch those computers into gauge mode and run a real table off of a lap top or my palm pilot. True deep stops start closer to 100', or deeper, and not 30' or 40' down. They will also get you out of the water somewhat faster.

I have not seen the new Uwatec "smart" computer, but I have dove with many of their other models and they line up, almost to the minute, with the Canadian Navy Tables- which used to be the Gold Standard of deco tables in the 80's and early 90's. I can say that if their program is close to the one in the Sunnto's that it still isn't there, but at least it's a step in the right direction.

All of the other tec divers I know who use Uwatec's have to trick them by setting the 02 setting very high to get them not to shut down on them for deco diving. This causes the most annoying situation of having the 02 alarm beeping at you for the entire time of the dive- which would other wise be nice and peaceful. A much better alternative is to buy one of the excellent Uwatec bottom timers that they make. It will save you cash and take you much deeper into tec diving.

An easy rule of thumb to get started with deep stops is to take your deepest depth for your deco stop and subtract that from your dive depth. Divide it in two and and subtract that number from you max depth. That should be your first stop. Do this again from the deep stop depth and your first deco stop and repeat as needed until you come up with a number less than 33'. THese are numbers to ADD into your regular deco profile.

Better yet, buy a copy of DecoPlanner off of the GUE website.

All of this would be taught in a proper deco class and should not be attempted by reading something off of the web. There are many other things that you need to take into account- gas consumption, 02 toxicity limits, bail-out supplies. Trying to run a deco dive on-the-fly with a computer has many probelms with it that show up too often in emergencies out on the lake. I have had to share air, and deco gases, too many times with people who weren't even my buddy becasue they thought they could just run deco off of a computer without really planning out the dive properly.

If you really want to get the low-down on deco theory without getting into tec diving, look into the DIR-F class that Deeper Blue is offering in June. They are flying in two of the best tec instructors in the world in from the west coast to teach it.

Jon

[Omicron]

I own, and use, the Uwatec SmartCOM. Honestly, it's a decent computer for recreational diving. Had I known more when I first started diving I probably wouldn't have bought it...but as it is, it's a GREAT recreational computer.

The thing that Colin is talking about isn't necessarily deep stops. There is a setting on the computer - L0 through L5. They call it "microbubble supression". Essentially what it does is reduces your bottom time and makes you do longer deco/safety stops. It could also induce deeper safety stops. It's Uwatec's new feature they are touting that is supposed to reduce the formation of microbubbles

I personally find it to be an annoying feature and I have mine set to L0 - off/disabled. I run the deeper safety stops on my own. Luckily the majority of my deep dives are planned in such a way so that I get my deep stops as part of the dive - in other words, I'm not doing a straight ascent and having to stop and hang for a minute at 80. We usually come up from depth and swim along at 100 for awhile, then move up to 80, then 60, etc til eventually we make it back to our exit/entry.

I'm not performing "true" deep stops but still the same concept. Slow ascents and diving at levels that give my body time to properly decompress.

[FreediveWI]

Sounds like a smart way to run your dives Omicron.

I have noticed that when I dive air and do the deep stops I feel just as good post dive as if I dove nitrox and didn't do the deep stops.

I realize that's only a data sample of 1 , but it worked for me. ;D

Jon

[Omicron]

It works out pretty good. I haven't been as good about it when coming up on a line from a wreck, but I'm getting better at doing a deep stop or two on a line. Practice makes perfect...

[Deep Blue]

This thread has opend up some interesting topics, but I would like to take it the advanced discussions section. The topic would be computers (both PC and wrist mounted) and their role in decompression dive planning. Hope to see you there!!!!!

[Omicron]

Sorry it took me so long to get that thread moved, I was gone for the weekend. Here to some more good discussion...

As far as planning deco dives with the majority of computers goes, I didn't really think it was possible for most of the major rec computers on the market. I can plan my dive with my SmartCOM but it doesn't ever show dive times past the NDL's...it would be kinda nice if I could somehow get it to do that.

[FreediveWI]

Back to the original thread.

This is a link to an article in the San Franscico Chronical a week ago about the law suit.

All of the divers mentioned in bringing the suit against Uwatec are highly qualifed technical divers, and instructors. One is even the president, and founder, of TDI!

Two of the others I have met and,or, dove with, David Sipperly and "Tuna". David was on The US spearfishing team a few years ago and is a published author on freedivng. "Tuna", is a trimix diver who did support work for Pipin, at 400', on some of his 500' sled dives a few years ago. I was fortunate enough to have him working as a safety diver for me when I was freedivng in Miami a few years ago- but NOT to 500'!

These were not newbie divers who got hurt because they didn't know any better. They were all highly trained divers who trusted their wirst computers a little bit too much.

Jon







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