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.. Folks,
This is FYI -- thanks.
>
> Cheers.
>
> Bruce And Tim
>
>
>> RGBM Validation And Testing Update
>>
>> The past few weeks following release of the NAUI RGBM ranged trimix,
>> helitrox, (soon EANx) Tables have been hectic, so accept our apologies
>> for not getting this out sooner. Some important facts about RGBM
>> validation and testing are listed for your information:
>>
>> 1) -- counterterror and countermeasures (LANL) exercises have used
>> the RGBM (full up iterative deep stop version) for a number of
>> years, logging some 327 dives on mixed gases (trimix, heliox,
>> nitrox) without incidence of DCI -- 35% were deco dives,
>> and 25% were repets (no deco) with at least 2 hr SIs, on
> forward profiles.
>>
>> 2) -- NAUI Technical Diving has been diving the deep stop
>> version for the past 2 yrs, some estimatd 200 dives, on
>> on mixed gases down to 250 fsw, without a single DCI hit.
>>
>> 3) -- modified RGBM recreational algorithms (Haldane imbedded
>> with bubble reduction factors limiting reverse profile,
>> repetitive, and multiday diving), as coded into SUUNTO,
>> ABYSS, Cochrane decometers lower an already low DCI
>> incidence rate of approximately 1/10,000 or less. More
>> RGBM decompression meters, including mixed gases, are
>> in the works (know of 3)
>>
>> 4) -- a cadre of divers and instructors here in mountainous
>> New Mexico, Utah, and Colorado have been diving the
>> modified (Haldane imbedded again) RGBM at altitude,
>> an estimated 350 dives, without mishap. Again, not
>> surprising since the altitude RGBM is slightly more
>> conservative than the usual Cross correction used routinely
>> up to about 8,000 ft elevation, and with estimated DCI
>> incidence less than 1/10,000.
>>
>> 5) -- within decometer implementations of the RGBM, not a single
>> DCI hit has been reported in the multidiving category,
>> beyond 1000 dives or more, up to now.
>>
>> 6) -- extreme chamber tests for mixed gas RGBM are in the
>> present works, and less stressful exposures will be addressed
>> shortly -- extreme here means 300 fsw and beyond.
>>
>> 7) -- probabilistic decompression analysis of some selected
>> RGBM profiles, calibrated against similar calculations
>> of the same profiles by Duke, help validate the RGBM on
>> a computational basis , suggesting that the RGBM has
>> no more theoretical risk than other bubble or dissolved gas
>> models (ala Weathersby, Vann, and Gerth methodology at USN/Duke)
>> This will be reported in a very technical paper/journal.
>>
>> 8) -- all divers and instructors using RGBM decometers, tables,
>> NET software have been advised to report all their profiles
>> to DAN Project Dive Exploration (Vann and Gerth and many
>> others at Duke).
>>
>> 9) -- ABYSS is a NET sotware package that offers the modified
>> RGBM (folded over the Buhlmann ZHL) and soon the full up,
>> deep stop version for any gas mixture, and has a fairly
>> large contingent of tech divers already using the RGBM
>> and has not received any reports of DCI.
>>
>> 10) -- outside of proprietary (commercial) and RGBM Tables,
>> mixed gas tables are a smorgasboard of no longer applicable
>> Haldane dynamics and discretionary stop insertions, as
>> witnessed by the collective comments of a very vocal and
>> extremely competent, experienced technical diving community.
>>
>> This process of testing and validation is ongoing, and we appreciate,
>> make that, ask for your help in reporting your RGBM dives to DAN
>> Project Dive Exploration and certainly to us with any "duress". This
>> receives immediate attention.
>>
>> Permit Tim and me a few comments about the RGBM and its roots,
>> since real pioneers very often go without proper recognition -- those
>> of us that follow reap the benefits of their insight and perspectives,
>> and our benefits of hindsight and modern diving developments. The
>> RGBM builds upon the work of Brian Hills and David Yount, skillful work
>> performed on phase mechanics, bubbles, and ultimately, first translations
>> of their findings to the diving arena and particularly, diver staging.
>> They didn't have all the answers (who does), but they underlined basics.
>> Both applied computer studies and simulations to diving profiles,
>> though much has not been recognized (til recently). True warriors,
>> they labored in difficult times, and under enemy fire, so to speak.
>> Hats off to you, Brain and David (and all your co-workers).
>>
>> Further for your information, Tim And I will be releasing all existing
>> RGBM Tables (ranged trimix and helitrox) and a suite of others (EAN24
>> to EAN36, constant PO2 heliox, and other ranged trimix and heliox) to
>> the Net, as with the Technical Diver Series, and under NAUI Technical
>> Diving auspices. The format is "groupless" with 2 allowable repets
>> per day, plus some other simple protocols.
>>
>> Thanks for your interest.
>>
>> Bruce Wienke and Tim O'Leary
>>
>> Los Alamos National Laboratory And American Diving And Marine Salvage
>> NAUI Worldwide Technical Training Operations
>> 3/24/00
>>
>
>
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