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From: <kirvine@sa*.ne*>
Date: Fri, 17 Sep 1999 09:46:53 -0400
To: Matt London <DIR-Asia@di*.co*>
CC: cavers@cavers.com
Subject: Re: Decompression Question
Matt, Jaba the Crea is partially correct here: he seems to recognize
that nitrox is not less nartcotic than air, yet not realize it is a poor
substitute for the correct gas, and may in fact me quite a bit more
narcotic and separately excitory in its higher absolute percentage forms
regardlesss of PPO2.

Just to clarify, as you mentioned, we use helium in the deeper deco
gases, and even in the shallow ones for this and other reasons.

I do agree with the Hut that most of what these bullshit "training"
agencies teach is a lie, as he suggests. Good to see that Jaba
recognizes this, now maybe he can stop promoting the all time big lie -
bondage wings. He is of course test pilot for the Slobwinder which as
you know comes with a pair of barbeque tongs for pulling out your tools
to take a piss after the dive - very handy.

Matt London wrote:
> 
> Thanks pal.
> 
> So are you saying that the effects of narcosis is the same
> at 35 meters as it is at 40 meters if the Nitrox mixture used is at a
> 1.6pp02 (deco gas)?
> 
> We've known about the narcotic effects of oxygen for years now,
> what's new and extremely interesting to the dives we are conducting here is
> the information that George
> has recently provided in the way of using helium at the 35 meter stop, not
> only with respects
> to the obvious reduction in narcosis but as a means to an even cleaner,
> accelerated decompression.
> 
> With all due respect.
> 
> M>
> 
> ----- Original Message -----
> From: <johncrea@in*.co*>
> To: Matt London <DIR-Asia@di*.co*>
> Sent: Thursday, September 16, 1999 1:41 AM
> Subject: Re: Decompression Question
> 
> > Matt,
> >
> > Of course, you know that there is absolutely NO EVIDENCE that NITROX is
> > less narcotic
> > than AIR at the same depth.
> >
> > I know that may training agencies continue to teach the LIE that Nitrox is
> > LESS NARCOTIC than
> > AIR at the same depth, but frankly, there is NO RESEARCH to support this
> > statement, and
> > there IS RESEARCH to support the contention that NITROX IS AT LEAST AS
> > NARCOTIC as AIR
> > at the same depths.
> >
> > Teaching your student this LIE is doing them a grave disservice.
> >
> > John
> >
> > At 10:01 AM 9/14/99 , you wrote:
> > >We've changed to EAN35 at 1.6 pp02 as our deepest
> > >  Nitrox stops and are quit happy with the results.
> > >
> > >Less narcosis makes for an even safer dive.
> > >
> > >With all due respect,
> > >
> > >Matt London
> > >
> > >Thailand's deep cave exploration at - www.divefun.com/tcdp/
> > >
> > >
> > >----- Original Message -----
> > >From: Dan MacKay <dmackay@cg*.wa*.ca*>
> > >To: <kirvine@sa*.ne*>
> > >Cc: <cavers@cavers.com>
> > >Sent: Wednesday, September 15, 1999 9:34 AM
> > >Subject: Re: Decompression Question
> > >
> > >
> > > > Hi all,
> > > >
> > > > I'd like to thank everyone who took the time to reply to my post. It
> was
> > >most
> > > > informative. I have always been of the opinion that when diving mix
> you
> > >have to find
> > > > the schedule that works best for you and the dive that you are doing.
> I
> > >tried breaking
> > > > on my back gas (16/50) during the deco 30 min bottom @ 210 and the
> > >difference was
> > > > amazing. No loggy feeling or low grade headache. I think that I will
> start
> > >carrying a
> > > > 120 mix and start using deeper stops. The deco so I will end up with a
> > >32/50/100 as I
> > > > was playing around with the tables and that combo seems pretty good.
> > > >
> > > > Thanks again.
> > > > Dan
> > > >
> > > > kirvine@sa*.ne* wrote:
> > > >
> > > > > We break to the most hypoxic mix we can breathe all the way up at
> least
> > > > > every twenty minutes, and in the oxygen phase we shorten that to as
> low
> > > > > as 12 minutes with up to 8 minutes off. We do not interrupt the
> shcedule
> > > > > for these "breaks". This routine spares the oxygen damage
> completely, as
> > > > > measured by vital capacity tests that day and the next few days.
> > > > >
> > > > > Take a look back at what the usdct idiots did - they fried all of
> their
> > > > > divers repeatedly due to ignorance of how to properly do this.
> > > > >
> > > > > The "clock" concept" is somewhat arbitrary and based on empirical
> > > > > evidence - the breaks have extended the time to tox in tests. More
> > > > > important, however, is the Navy experience which says that tox risks
> > > > > comes in multiday exposures, so keep that in mind.
> > > > >
> > > > > Dan MacKay wrote:
> > > > > >
> > > > > > Hi George and to anyone who might have an answer,
> > > > > >
> > > > > > On my longer dive profiles which are typically 30 - 50 minutes @
> 250',
> > >I always
> > > > > > use a 16/50 mix with 50% & 100% for deco. At the end of these
> dives
> > >(or longer
> > > > > > duration) I have blown my CNS clock away. For a 50 minute exposure
> I
> > >have a total
> > > > > > CNS clock of ~180%. This does not appear to cause me a problem as
> I
> > >have been
> > > > > > doing a couple of dives a week using profiles like this for a
> couple
> > >of years now
> > > > > > and this has not proved a problem. The only time I think that I
> ran
> > >into this as
> > > > > > a problem was about 4 years ago when I was diving a lot of deep
> air
> > >with 36 and
> > > > > > 80 for deco (ok it was before I saw the light) on the last two
> dives I
> > >did in a
> > > > > > two week period I couldn't breath by the time I hit my 20' stop.
> > >Symptoms didn't
> > > > > > abate till I was on the surface for about 15 min. In anycase I
> don't
> > >do that now.
> > > > > > I know this is small potatoes compared to what you and JJ do on a
> > >normal WKPP
> > > > > > dive. What do you do just ignore it? or what is your philosophy on
> > >this?
> > > > > >
> > > > > > Thanks,
> > > > > > Dan
> > > >
> > > >
> >
> >
> >


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