RGBM conservatism

[BRW]

G,

Go back and read Charlie99 post.

Notice I said "rec RGBM" computers -- not full up mixed
gas computers . Such rec computers are in short supply at
Mares, Dacor, Suunto.

And here's more that maybe clarifies.

Deep stops are in RGBM Mares and Dacor rec units released in June. Trimix computer with same is in the works. All are RGBM with said same bubble dynamics as described above. Deep stops come from folding over full RGBM.

Suunto will be extending a deep stops deco version
to Vytec, Vyper, Cobra, Mosquito (whole line). Present
Suunto line is rec RGBM as described.

HydroSpace Explorer IS "real" trimix, deco computer
with full scale RGBM -- ONLY one now. But Zeagle, Mares,
Dacor, Plexus, Steam Machines following suit. Suunto
contemplating. These are RGBM computers targeted at
tec diving, and handle rec diving too. Deep stops fall out of the
model directly -- "real"

Zeagle is working on a "real" RGBM computer for mixed gases.

Steam Machines will have "real" RGBM computer in RB units
(Prism, Topaz, USN Invader), and just started work.

Rec RGBM, real RGBM, or RGBM in between computers all
are going on "backorder at vendors".


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

 

[Diver0001]

Bruce,

Since we're now on the subject of a specific computers, I was thinking about buying a computer to backup tables for technical nitrox dives (think in terms of IANTD advanced Nitrox/deco specialist). The computer I have now is an old air-only Genesis that gives me NDL's that bend most modern computers.....LOL.

The computers I've been looking at that have the features I need are the Nitek-3, the VR2, (VR3's little brother) and the Suunto Vytec.

Of those only the Vytec claims to have RGBM but if I understand Charlie correctly it isn't really.

The VR2 is strictly dissolved gas but it has deep stops built in and the HE version has a good reputation in Tek circles. The VR2 is a really feature rich computer but (although price is pretty much my last concern) I can get the Vytec for free because I DM for a Suunto dealer. I'm really tossing around with this decision.

Do you have any words of advice? Should I wait until the deep-stop version of the Vytec comes out? Do you know when that will be?

R..

BRW once bubbled...
G,

Go back and read Charlie99 post.

Notice I said "rec RGBM" computers -- not full up mixed
gas computers . Such rec computers are in short supply at
Mares, Dacor, Suunto.

And here's more that maybe clarifies.

Deep stops are in RGBM Mares and Dacor rec units released in June. Trimix computer with same is in the works. All are RGBM with said same bubble dynamics as described above. Deep stops come from folding over full RGBM.

Suunto will be extending a deep stops deco version
to Vytec, Vyper, Cobra, Mosquito (whole line). Present
Suunto line is rec RGBM as described.

HydroSpace Explorer IS "real" trimix, deco computer
with full scale RGBM -- ONLY one now. But Zeagle, Mares,
Dacor, Plexus, Steam Machines following suit. Suunto
contemplating. These are RGBM computers targeted at
tec diving, and handle rec diving too. Deep stops fall out of the
model directly -- "real"

Zeagle is working on a "real" RGBM computer for mixed gases.

Steam Machines will have "real" RGBM computer in RB units
(Prism, Topaz, USN Invader), and just started work.

Rec RGBM, real RGBM, or RGBM in between computers all
are going on "backorder at vendors".


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

 

[Diver0001]

I think you're missing the point somewhat. RGBM really comes into it's element once you've gone *over* the NDL.

And even at that..... Stats indicate about 1:100000 DCS rate overall but you get a very different rate of DCS once you study only aggressive multi-day repetative diving like you get on live-aboards. RGBM, from what I've heard, has an application in this area too. (multiple repetative dives).

But you're right to point out (if I read you correctly) that the computer is only a tool and how you dive is more important than the instrument you carry.

R..

DeepScuba once bubbled...
I guess it's a good thing I don't care to waste much time with it.

Basically I'm a "what works, works" type of guy. Although knowing some things give me great pleasure in its understanding, the simple fact that, even though DCS is "real", the true math of it all will forever be unknown with all its human factors etc.

Basically I don't give a crap! I dive my dives with mucho conservatism, and whatever happens, happens.

Simple, and not much learning involved. There have been millions upon millions of dives, both rec and tec, with over 99.99% of them without DCS incident while diving within their perspective limits........RGBM may be XXXX, but it's mostly background noise to those that dive within the prescribed limits to begin with.

I wish for the life of me I could put a finger on the article so I could at least give it it's due.


Regards

 

[DeepScuba]

Actually Rotuner, I said as much in my earlier post. It comes more into play during Tec, than Rec, as I understand it.

This is why, when I do Deco Diving, I incorporate deep stops.

I am a pretty darn cautious guy, and I don't have to understand like BRW obviously does, to know that D/Stops AND doing all my deco is a good thing

Although I am a fan of computers, my plan is planned long before I enter the water, the computer at that point is the back-up, regardless of the model it uses.

 

[Dr Deco]

Hi paulwlee:

Sleeping

During the surface interval, I would suggest that sleeping is to be avoided. In this state, the metabolism is slowed down and the blood flow is considerably reduced. Nitrogen washout is at a minimum, something you do not wish to occur during the surface interval.

DCS Incidence

Divers should recognize that if a table has a 1 % DCS incidence rate, 99% of divers could perform that same dive without problems. The spread in susceptibility to DCS is very large judging from the few laboratory studies that exist. It is of value to remember that decompression algorithms are made to protect the “slowest boy in the class.”
You are a DCS-susceptible diver if:

• you have an as-yet undetermined “something” (possibly a low surface tension)
• are poorly hydrated
• produce nuclei from musculoskeletal work. :lifter:

A good dive computer and poor dive skills on the boat can get you into trouble just as fast as a good GPS with a lack of backcountry skills.

Dr Deco :doctor:

 

[Charlie99]

Diver0001 once bubbled...
Since we're now on the subject of a specific computers, ........
The computers I've been looking at that have the features I need are the Nitek-3, the VR2, (VR3's little brother) and the Suunto Vytec.

Here is an interesting report on computers done by a local diver. First he recorded the displayed calculations several computers in response to two 30 meter dives of 16 minutes. Includes Nitek3, Vyper, VR3, as well as Mares M1 and an Oceanic.

Then he converted the results to an equivalent hi/lo GF set by finding what settings in DecoPlanner generated results close to what the computer had displayed. Your old Genesis is probably the same as the Aeris/Oceanic --- GF of 96/97.

The Nitek-3 comes in surprisingly conservative... equivalent GF of 41/80. This matches my experience of a couple months ago where a dive buddy's Nitek-3 was showing less NDL than my hockey puck, even though he had deco'd out on EAN50 (and had done the gas switch on the Nitek). If you are used to diving the Genesis to the limits, you probably would not be happy with the Nitek.

Charlie

 

[BRW]

DeepScuba

Yeh, rec stats for DCS are in the 1/75,000 range as
reported in many articles, Wkshps, etc. And that's a good
thing.

In those low stats, the cases that DO stand out as more
problematic are RPs in the 40 fsw and greater range,
short SIs less than an hour, 3 -4 repets a day for 5 -6 days,
and altitude diving. RGBM ADDRESSES those problem
areas with bubble dynamics and drops the DCS rate lower.

End result for rec divers is that the RGBM estimated
incidence rate is something like 1/200,000.

That's an even better thing -- for divers and meter
manufacturers.

NOT one case of DCS has been reported by RGBM
meter folks in (now) millions of rec dives. Similar
reports from the EXPLORER tec computer on fewer
tec dives, of course.

On models, remember it's not just models, but correlation
with data which is only possible if coarse grain dynamics
are in place. The above problem areas could never be
addressed within just dissolved gas models, as many have
tried and failed, and reported so. And when you go to
the broad world of mixed gas, deco diving, models are
even more important and differences become totally
overwhelming. That's were coarse grain RGBM dual
phase dynamics provide closure for theory and real
diving apps and stats.

=-)

Regards,

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

 

[BRW]

Diver0001,

The RGBM EXPLORER fits your needs for a dual phase computer
for tec diving (deco, mixed gas of any kind). It's full up
RGBM, as I mentioned in my earlier posts. And it handles rec
diving exactly the way other rec computers do. EXPLORER
also comes with an RGBM simulator for your PC.

It's not cheap -- $1200.

There will be three other tec-to-rec RGBM computers out
there pretty soon, that is full up ("real") RGBM. They
are Zeagle, Mares, and Dacor. Suunto is cogitating on
one possibly. If you dive RBs, Steam Machines will have
full up RGBM in their Prisms, Topazs, and USN Invaders
(yeh SEALs).

Regards, and good diving,

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

 

[Genesis]

NOT one case of DCS has been reported by RGBM
meter folks in (now) millions of rec dives. Similar
reports from the EXPLORER tec computer on fewer
tec dives, of course.

By your own subsequent post there is exactly one current "real" RGBM computer - the explorer.

This "not one case" claim is more than a bit suspect, given that, from your very own statements, only one, very expensive, technical computer currently is sold with "real" RGBM in it.

So how did these "millions" of recreational dives get done on an RGBM implementation when, today, there is no such thing as a full-up RGBM recreational computer?

I smell marketing-speak in an attempt to promote possible future sales, to be polite about it.

 

[BRW]

G,

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

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.

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.

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