RGBM conservatism

[Charlie99]

BRW once bubbled...
Rec stats comes from Suunto, Mares, Dacor.

Plus from released NAUI RGBM Table for rec air, EAN32, and
EAN36.

Yes -- no DCS reported on these RGBM offerings.

Will some DCS ever occur? OF COURSE. For data
analysis, though, minispikes in DCS rate are what
need "trends" attention.

Are you saying that nobody has ever gotten bent while diving inside the limits of a Suunto Cobra, Vyper, Vytec, etc?

 

[Genesis]

No, I am not on the marketing staff of anybody.

That's demonstrably false. You have a pecuniary interest in what you're discussing here.

RGBM rec computers are not mixed gas, deco
tec computers but do have full RGBM bubbles dynamics
rolled over their recreational ranges. In rec ranges,
the concern areas are the ones spelled out. Think this
has been said often, and is generally well known.

For rec diving, nobody needs an EXPLORER.

You are correct.

But the Suunto implementation isn't quite clear; I don't own a Mares/Dacor M1, so I can't comment on it in detail, but I DO own several of Suunto's products.

What is "diving within the limits" of the computer, specifically, related to this? Is it a violation (and thus doesn't count) if I go back in the water with a suunto displaying its "attention" symbol? If I got bent doing that, would it count as a "bend"?

Not picking on 'ya just for fun here Bruce - unqualified statements without specifics raise the hair on the back of my neck, as my training and education is in scientific disciplines - where uncertainties are to be specified on measurements and statements, particularly ones of absolutes, are to be qualified.

Eat more turkey!

 

[BRW]

C99,

Nothing reported to me in just RGBM Suunto stats.

Like I said, one will occur. Maybe has.

As time goes by, expect to see some Suunto, Mares,
Dacor, etc hits on even a 1/200,000 rate. Has to be.

Trends are the important statistic though, and we
watch them closely. Some noted trends have been
already addressed by rec RGBM.

Regards,

Bruce Wienke
Program Manager Computational Physics
C & C Dive Team Ldr
NAUI BOD Vice Chairman Technical Diving

 

[Chopper]

I have read with much interest all this discussion about the Suunto RGBM and it has answered many of my questions. I came along looking for answers as to the following: I noticed when using my Suunto Vyper for deco dives that it was bringing me up very shallow to deco, ie. typically giving me 3m ceiling for anything in the 30-40m range. This seems to be contrary to my understanding, in that RGBMs should introduce deep stops to smooth out the deco profile. I now learn that this ‘recreational’ RGBM is not the full implementation and it’s mainly for divers who avoid necessary deco. I’m not happy with such a shallow ceiling, and generally ascend slowly and stop deeper than the computer says. Funnily, enough, buried in the small print in the Vyper instruction booklet, it recommends deco-ing at below 4m!! Well, I thought, no matter. I’ll follow the decompression ‘floor’ which should allow me to off-gas more slowly whilst staying a bit deeper. According to the instructions, the ‘floor’ is represented by the upward pointing arrow (ie. the lower half of the ‘hourglass’ icon), which disappears when you enter the deco zone. The deco zone should start when the leading tissue reaches a sufficiently low ambient pressure to begin off-gassing. Well following the Vyper, this doesn’t seem to be the case, since the ‘floor’ seems to be not much below the ‘ceiling’ ie. about 6m. This is very misleading as it represents the most efficient deco zone and not the real ‘floor’ at all. In fact, when I analysed some dive profiles using the desktop software, it seems that the leading fast tissues start off-gassing and the slow tissues stop on-gassing about where you’d expect them to, ie. about where you would put in the first deep stop, which is half the maximum depth minus the first stop ( about 15m for a 35m dive). Presumably this is at or close to the real ‘floor’. OK, so the Suunto RGBM is not the full implementation, as it doesn’t put in the deep stops. It seems that for the most part the modifiers affect what happens on the surface and for following dives in a series rather than actually modifying the dive profile itself. That’s fine, I still thing RGBMs are the way forward, but can anyone tell me what would happen if, using the Vyper in normal air/nitrox mode I put in the deep stops ? Would it penalise me unduly ? or is a foolhardy thing to do given the way it works ? Should I use it in Gauge mode for serious dives and use dissolved gas tables with gradient factors or go out and buy a new one with the full RGBM ??

Cheers,

 

[chrisch]

Wait sound right....

Sounds to me like anyone wanting a new computer should wait a bit until the new generation of RGBM models come out and get a trimix compatable one. I really hope the manufacturers can get these out at a sensible price and realise many of us want to do the odd trimix dive but mainly use EAN and rec. profiles.
Chris

 

[Captain_ltd]

Hello Bruce,
When the data base on the profiles of diving will be available on http://www.rgbmdiving.com/site/rgbmdata.htm ??


Regards,

Jérôme