HDTenEightyP/NetNews huggingface dataset:
From: gd@gehenna.sw.stratus.com (Greg Dawe)
Newsgroups: rec.scuba
Subject: Re: dangerous misconception (was Re: Human bodies explode...)
Date: 16 Nov 92 16:38:42 GMT
Organization: Stratus Computer, Software Engineering
NNTP-Posting-Host: gehenna.sw.stratus.com

In article <1992Nov16.150349.18126@klaava.Helsinki.FI> mluoto@klaava.Helsinki.FI (Markku Luoto) writes:
>
>	Hmm... 300ft or so being uniformaly dangerous because of oxygen
>becoming oxiduous / poisonous or what ever...
>
Human oxygen tolerance limits are not well defined, but NOAA does publish
guidelines in terms of PO2, activity level, and exposure time.  For 
example, I believe the NOAA table specifies a maximum of 45 minutes for
a resting diver breathing a gas which has a PO2 of 1.6 ATAs.  So, for air,
which we'll say is 21% O2, this guideline would translate to a maximum
operating depth of 218 FSW for a diver at rest, clearly much more shallow
than 300 FSW.  Perhaps this is why the US Navy's working diver air/SCUBA 
limit is 190 FSW.  The textbook for the IAND NITROX course contains some 
good information, including the NOAA PO2 exposure tables.

Several notable diving physiologist, such as RW Hamilton, have published 
various models, for quantifying hyperbaric O2 dosages.  If you're into
physiology or math, Hamilton's paper on Oxygen Toxicity and the Repex Method 
might be interesting reading.  

The Reverend Edward Lamphier, who helped pioneer the US Navy's work on
defining human O2 toxicity limits, published an article in AquaCorp's
DEEP or MIX issue (can't remember which).  This article is exceptionally
well written, is easy reading (it's geared towards people like me, who
do NOT have a PhD in math or physiology), and puts O2 toxicity in real
perspective - meaning that we don't know as much as we should.

Why can some people dive to 300 FSW and not die, while others convulse and
drown at 210 FSW?  Some of the contributing factors are known, but the
whole mechanism is not well understood.  The bottom line is that this kind
of diving, on recreational SCUBA equipment is dangerous, and  CNS Oxygen 
Toxicity is just one of the risks.  Those who venture deep on air must 
understand and accept those risks.
-- 
Greg Dawe                        | Disclaimer: I don't speak for my employer,
Voice : (508)-490-6666           |             nor they for me...
e-mail: Greg_Dawe@vos.stratus.com|
From: Jordon Weinstein <jweinstein@igc.apc.org>
Newsgroups: rec.scuba
Date: 16 Nov 92 21:07 PST
Subject: grand cayman 12/4-11
Nf-ID: #N:cdp:1458600001:000:377
Nf-From: cdp.UUCP!jweinstein    Nov 16 21:07:00 1992


Going to Grand Cayman, Sunset House December 4-11.  Interested in any info from divers wh[from
divers who've been there.  Lodging comes with dive package, but not sure if I should
should get the dive package or wing that on my own.  Anyone out there who's 
going to be there Dec. 4-11.  Suggestions on best dive sites, off-island excursion-
sions, on-island things to do, etc.

Newsgroups: rec.scuba
From: wgreen@eckhart.scd.ucar.edu (Wayne Green)
Subject: Re: Definition of "Recreational Diving"
Organization: Scientific Computing Division/NCAR, Boulder, CO
Date: Wed, 18 Nov 1992 20:35:36 GMT

Cozumel recently introduced a 90' limit to dives in their
area. After many dive trips with tourists, it is not
difficult to see why a 'recreational' diver should be
conceptually separated from the diving sport inthusist.
We recommend students take full responsibility for their
actions, and not let themselves be led into a diving
situtiation beyond their training and experience.

The definition of recreational diver should be honored by all
responsible divers along the lines of a person who will enjoy 
hiking paved trails of America's national parks. Advanced
divers must define the limit of their recreational
activities to meet personal safety goals. An advanced
diver should not push the limits of their group to meet
their own advanced abilities or enhanced desires. As advanced
divers, we promote safe enjoyment of the sport to maintain
open bounds for advanced enjoyment of the sport. We have
one case where the Mexican government has imposed a limit
to prevent the accidents seen there by unresponsible 
participation of divers going beyond the range of thier
abilities.

It is possible to obtain dive instruction on mixed gas diving, 
deep cave exploration, ice diving, and other extremely 
hazardous activities - as an amatuer, and being  unaffiliated 
with any scientific or commercial interest.  The responsibility is 
up to the individual.


These are my thoughts alone.

Wayne Green      NCAR (National Center for Atmospheric Research)
FL2-1042         (303) 497-8540  FAX (303) 497-8520
P.O. Box 3000, Boulder Colorado, 80307-3000 wgreen@ncar.ucar.edu
SSI AOWI-4389
--

Wayne Green      NCAR (National Center for Atmospheric Research)
FL2-1042         (303) 497-8540  FAX (303) 497-8520
P.O. Box 3000, Boulder Colorado, 80307-3000 wgreen@ncar.ucar.edu
From: cordner@magician.larc.nasa.gov (Dave Cordner)
Newsgroups: rec.scuba
Subject: REQ: Diving Information for CANCUN (not Cozumel)
Date: 18 Nov 1992 18:26:07 GMT
Organization: NASA Langley Research Center, Hampton, VA  USA
Distribution: world
NNTP-Posting-Host: magician.larc.nasa.gov

I am going to be in Cancun over New Year's.  Does anyone have any information on scuba trips originating in Cancun?  I have been to Cozumel and taken trips from there, but I was hoping that I could catch a day trip out of Cancun without having to take a ferry to Cozumel.  

If there are day trips in Cancun, do they dive locally or at Cozumel? (or both?)

Thanks,

David Cordner
cordner@quickdraw.larc.nasa.gov
From: leej@sgi.com (Lee Jones)
Newsgroups: rec.scuba
Subject: Re: Diving in CA over Thanksgiving
Date: 19 Nov 92 22:28:20 GMT
Organization: Silicon Graphics, Inc.
NNTP-Posting-Host: diver.asd.sgi.com

In article <1992Nov19.204644.5342@nevada.edu> tierney@nevada.edu (TIMOTHY P TIERNEY) writes:
>
>You can also dive the Colorado River below the dam.

Tim - years ago I read about a guy that runs dive charters on the Colorado - 
supposedly it's a real E-ticket ride zipping past surprised trout at 
Warp 3.  Do you know of such a charter - names, phone numbers, etc., and 
what the reputation of things is?  (Like, is it safe for open water 
type divers that don't have "white water diving" experience?)

Regards, Lee
From: gd@gehenna.sw.stratus.com (Greg Dawe)
Newsgroups: rec.scuba
Subject: Re: dangerous misconception
Date: 16 Nov 92 17:35:13 GMT
Organization: Stratus Computer, Software Engineering
NNTP-Posting-Host: gehenna.sw.stratus.com

In article <1992Nov16.134956.27168@herboid.uucp> adb@herboid.uucp (Anthony DeBoer) writes:
>David Weingarten <davidw@cie.uoregon.edu> writes:
>
>Um, it's my understanding that there are a few individual-susceptibility
>factors that enter into it; it's not like everybody is perfectly safe at
>297' and dead at 299'.  Also, work level makes a big difference.  If
>you're resting, you can take a much higher partial pressure of oxygen than
>if you're exerting yourself.
>
This is generally accepted as true, but there appears to be some rumblings
within the UHMS that higher concentrations (fractions) of O2 may cause 
higher susceptability to CNS O2 toxicity.  In other words, breathing pure
O2 at 20 FSW (PO2=1.6 ATAs) may be riskier than diving to 218 FSW on air
(PO2=1.6 ATAs) if all other circumstances are equal.  As far as I know, there
is nothing published on this - it was just TALK during a seminar I attended
on in-water Oxygen Decompression.  Anybody heard anything else?
-- 
Greg Dawe                        | Disclaimer: I don't speak for my employer,
Voice : (508)-490-6666           |             nor they for me...
e-mail: Greg_Dawe@vos.stratus.com|
From: ellenc@ogma.csd.sgi.com (Ellen Campbell)
Newsgroups: rec.scuba
Subject: Diving Ideas In Mexico?
Date: 23 Nov 92 22:59:16 GMT
Organization: Silicon Graphics, Inc.

Hey fellow divers:  

I would like some suggestions, please.  Some friends of mine are interested
in diving in some of the warmer waters the Pacific Ocean has to offer.  The
operative word is "inexpensive," oh, all right "cheap" is more like it. 
(There are a couple of graduate students in the group.)  We were thinking
of Baja.  Does anyone know where to dive and where to stay?  There is also
a possibility that they might opt for So. Calif.  any ideas about that area
too?

Thanks for you time and efforts in answering this.   ellenc
From: jdale@cats.ucsc.edu (Jonathan Dale)
Newsgroups: rec.scuba
Subject: Re: dangerous misconception (was Re: Human bodies explode...)
Date: 16 Nov 1992 19:48:02 GMT
Organization: University of California; Santa Cruz
NNTP-Posting-Host: si.ucsc.edu


In article <1e8dgiINNafa@transfer.stratus.com> gd@gehenna.sw.stratus.com (Greg Dawe) writes:

>On a more technical note, it's not completely accurate to state that "anybody
>diving to 200' and deeper is going to be SERIOUSLY narc'd".  There are some
>divers who are able to function well at 200 FSW, and a rare few, who can
>function well even deeper.  These divers have been diving deep on air for
>years, and have developed some tolerance for the symptoms of narcosis.  They
>also understand their body's limitations while "under the influence" and don't
>stray too far from the anchor line, nor do they exert themselves.

>This tolerance, or adaptation is finite.  It has a "bottom" (as opposed to
>a ceiling), and can be lost if the diver doesn't continue to dive deep.  
>In areas of seasonal diving, such as New England and Long Island, deep divers
>spend the initial part of the season diving progressively deeper to regain
>their deep adaptation/tolerance.

I would question this whole tolerance concept.  Based on what I've been taught
and my personal experience, it seems that nitrogen narcosis affects mainly
judgement and creative thinking.  It tends NOT to affect performance of
routine acts.  Thus, an experienced diver who has been diving recently so
everything is fresh in his/her mind will be able to do a deep dive, no problem,
as long as nothing weird happens.  But, we have had people here -- an 
instructor, even, I think -- mention that they were completely unable to 
comprehend an unusual flashing light on their console while they were at depth,
and they just sat there for several minutes until the console gave a more
clear message (it said "GO UP").  I also know people who do deep research
(~100') who do fine at depth, but who were unable to make decisions down
there (in this case, they were unable to decide which camera to use, and had
to abort the dive).  

One of my classes went to 110' to do math problems, simple addition and
subtraction.  Some of us got them all wrong.  Myself, I got everything right
and felt fine -- sounds like natural tolerance, right?  That's what I thought,
down there.  I wasn't till I realized how long it was taking me that I 
realized that something was up.  You can be very solidly fixated on something
and do it all perfectly, and not even notice the weirdness.  How can you notice
when your sense of time is altered?  I think a lot of these people who think
they are immune or tolerant are just not noticing, and they won't notice until
they're forced to think, or react to totally new circumstances, and then 
they'll be in as much trouble as the rest of us.  More, actually, because
they're overconfident.
From: davidw@cie.uoregon.edu (David Weingarten)
Newsgroups: rec.scuba
Subject: dangerous misconception (was Re: Human bodies explode...)
Date: 16 Nov 92 07:45:47 GMT
Article-I.D.: nntp.1992Nov16.074547.5322
Organization: University of Oregon Campus Information Exchange

BONG! Sorry, that is not the correct answer.  Thank you for
playing, please try again.

Nitrogen Narcosis can occur at depths as shallow as 70-80'.
SYMPTOMS occur generally at depths around 120'-140'.  That is,
beyond 100' and you can have truly hazardous effects.  This is,
of course, dependant on your personal susceptability.

At 300', OXYGEN TOXICITY occurs.  This an ENTIRELY DIFFERENT
problem and is MUCH more hazardous.  Oxygen Toxicity happens
suddenly and as subtly as a sledgehammer to your head.  It
causes violent convulsions and unconsciousness, and, as a result,
death.  This is not something that we are individually susceptible
to; it's pretty uniformally deadly, at about 298'.

Anybody diving to 200' and deeper is going to be SERIOUSLY narc'ed.
Whether they feel panicky, euphoric or start hallucinating varies
from person to person.  But at 300', getting narc'ed is the LEAST
of your worries. 

Had to clear that one up quick.  :-)

			-- David
			NAUI DM #D7355

p.s. Please be sure about such things before posting them.
300' for N2 narcosis is a hazardous misconception.  And, as 
much as people should always check things they read on the
net, many people don't.
Newsgroups: rec.scuba
From: craig@cattnts.canada.ncr.com (Craig Campbell)
Subject: Re: dangerous misconception (was Re: Human bodies explode...)
Organization: AT&T / NCR Canada Ltd., Toronto, Canada
Date: Tue, 17 Nov 1992 13:16:37 GMT

In article <1992Nov16.145952.5495@mailer.cc.fsu.edu> mayne@cs.fsu.edu writes:

>While on the subject of dangerous misconceptions, oxygen toxicity
>doesn't kick in suddenly at 298', nor does it usually strike without
>any warning. 
>Note that I said it doesn't *usually* strike without
>warning, not that you can count on getting any warning. But since
>it can happen at much less that 300' and there may be some warning
>symptoms it is wise to know the symptoms so if you are pushing the
>limits, or start to have problems within the usual limits (which is
>possible), you can abort the dive.

>Bill Mayne

Bill, in my Nitrox course, we were taught almost exactly the opposite.
Yes, there are a string of different symptoms which accompany O2 toxicity,
and people who have suffered from this and survived it report having most,
if not all, of the symptoms.  The scarry part is that the majority (apparently)
reported having the symptoms in a quick succession (like a second or two).
Not enough time in which to react.

The moral?  If you think you might detect even one symptom, get to a more
shallow depth immediately.  Don't wonder, or ponder the symptom, move!
Think about it after the dive.  (But that was basically Bill's moral as well.)

craig
-- 
Craig Campbell		|	These opinions are entirely the result of a 
Systems Engineer	|	small butterfly crashing into the far side
NCR Canada,		|	of the planet.  Chaos Rules.
an AT&T Company		|	I speak for no one, except, possibly, myself.
Newsgroups: rec.scuba
From: cs4gp6bm@maccs.dcss.mcmaster.ca (Phillips     D)
Subject: Manufacturers of Dry Suit Accessories
Organization: McMaster University, Hamilton, Ontario, Canada.
Date: Tue, 17 Nov 1992 02:41:20 GMT


A friend of mine is looking to start up a dry-suit repair
business.  Is there anyone out there who knows the names or
numbers of manufacturers of dry suit repair accessories?  He has
been searching for manufacturers of items like latex parts,
solvents, resins, glue, tapes, etc, and can not come up with a
source.  My friend would like to buy direct, and in large
quantities.  Names of known manufacturers in any part of the
world would be appreciated.


Darren Phillips
From: leej@diver.asd.sgi.com (Lee Jones)
Newsgroups: rec.scuba
Subject: Which Nitrox certification?
Date: 18 Nov 1992 21:13:00 GMT
Organization: Silicon Graphics, Inc.
Distribution: world
NNTP-Posting-Host: diver.asd.sgi.com

I am interested in taking a Nitrox course and getting certified in its
use.  However, I have difficulty telling which program is better, IAND or
ANDI.  Could somebody who's been through one (or preferably both) give me a 
"compare and contrast" kind of summary here?  

Thanks, Lee
Organization: Carnegie Mellon, Pittsburgh, PA
Newsgroups: rec.scuba
Date: Sun, 22 Nov 1992 16:47:45 -0500 
From: "Peter A. Simon" <ps3p+@andrew.cmu.edu>
Subject: Re: Down Currents (Was Cancun or Coz)

Excerpts from netnews.rec.scuba: 19-Nov-92 Re: Down Currents (Was Canc..
by Dan Kell@resonex.com 
> There was a discussion, some months? ago, about this phenomena. It does
> exist. I read an article some time ago in National Geographic about >Monterey
> bay that talked about down currents being an erosive force in the Monterey 
> Canyon. Cozumel was mentioned in the discussion quite extensively if I 
> remember right. I seem to remember something about the sand falls down
> there also. What ever.
>  
> I tend to disagree that loss of buoyancy control can be blamed for this.
> than us males B-) ), we are not fish. I sure can't out swim anything

[stuff deleted]

> we fins, I've tried. Somebody made the comment that if caught in a
> down current to swim towards the wall. I remember the consensus being
> that swimming away from the wall was the quickest way out of the 
> current. (Somebody mentioned swimming toward the wall, this may do
> nothing more than getting you smashed into the wall and pushed deeper.)
>  
Six or so years ago UCSB was conducting submersible operations in
Monteray Canyon using Can Dive Service's "Deep Rover."  The hot spot was
a wall which we'd hit at 2000' (this was not necessarily the bottom of
the wall).  The wall rose about 1000'.  When diving on a falling tide
(according to the tide tables for Monteray Bay), the pilots would
experience a definite "down-thrust" with the sub suddenly descending at
a great rate of knots.  The solution was to use both thrusters and
buoyancy tanks to counter the movement.  While terrifying at first, it
became just part of the game after several experiences.  We never
determined the cause.  It could have been caused by either current or
decreasing water density (due to change in temperature and/or salinity).
 It was not obviously current because it was not accompanied by any silt
or debris, nor gross reaction by the sea life (fish swiming into it,
soft coral being bent).  I have not seen the National Geographic article
but would tend to believe their conclusions.

I didn't write this before because 1000'-2000' is not your normal scuba
diving depth but since somebody brought it up...

Peter 
NAUI Inst. #1434
former Operations Supervisor and chief pilot of "Deep Rover."
From: dddurda@pine.circa.ufl.edu (DURDA)
Newsgroups: rec.scuba
Subject: FOR SALE: 100 cu. ft. tank with Y-valve
Date: 23 Nov 92 18:58:12 GMT
Reply-To: dddurda@pine.circa.ufl.edu
Organization: University of Florida  (ufl.edu)
News-Software: VAX/VMS VNEWS 1.3-4


  For anyone in the Gainesville, FL area. I have a relatively new (less
than one year old), black 100 cubic foot aluminum tank with a Y-valve up
for sale. The tank includes: protective mesh and boot, band with D-rings,
and surgical tubing retaining bands. All ready to go cavern or single-tank
cave diving. $190.

  Contact:

    Dan Durda
    (904) 373-0536  (H)
    (904) 392-7678  (W)
    durda@astro.ufl.edu


Newsgroups: rec.scuba
From: marcus@vestek.com (Mark Stephen)
Subject: Caffeine and Diving
Organization: Vestek Systems, San Francisco
Distribution: usa
Date: Mon, 16 Nov 92 19:14:31 GMT

     Does anyone have any info about the effects that caffeine can
have while diving, or caffeine withdrawls ?

     Marcus
From: story@sgi.com (David (Duis) Story)
Newsgroups: rec.scuba
Subject: Definition of "Recreational Diving"
Date: 18 Nov 92 19:29:23 GMT
Article-I.D.: twilight.shc0abo
Organization: Silicon Graphics, Inc.

In article <1992Nov17.153453.7235@digi.lonestar.org> lvogt@digi.lonestar.org (Lee Vogt) writes:
>
>
>If I'm not mistaken, the 130' limit applies to ALL recreational SCUBA diving,
>as going deeper than that requires *planned* decompression stops, at which
>point it's no longer recreational, but professional, diving.  

It should be pointed out that "Recreational Diving" is a term invented
and propagated by PADI, and that its definition is "(optionally
repetitive) no-decompression diving to less than 130fsw."  As long as
you understand that this is primarily a definition of convenience, not
a basic, undisputable definition, you'll be fine.  Just don't force
anyone else to dive according to PADI's definition of "recreational
diving" and you'll be fine.

It should also be pointed out that "safety stops" (3 minutes at 15fsw)
are REQUIRED by most modern tables (including PADI's most recent
editions of the RDP) after research dramatically proved that they
reduce silent bubbling.  

Gee, even "recreational" diving now has required, planned decompression stops.

> [...]  I would highly
>recommend the PADI courses to anybody wanting to learn to SCUBA-dive.   

I'm not surprised.  


Cheers,

David Story                        NAUI AI Z9588, PADI DM 43922, EMT
story@bent.wpd.sgi.com             Please don't be ethnocentric.
Organization: University of Illinois at Chicago
Date: Sunday, 15 Nov 1992 20:40:39 CST
From: MATT HUNSAKER <U61474@uicvm.uic.edu>
Newsgroups: rec.scuba
Subject: NITROX 2

I have recieved a number of hate mail responses for my note on NITROX. I
thought it was amusing that it came from both sides.  I was going to post each
of them here for everyones enjoyment, but some were so ridiculous I felt it wou
ld only perpetuate the ignorance of some of those misguided people.  I think
they champion ignorance just fine on their own.  In opposition to the expert
 diver who identified himself as such (undoubtedly so I wouldn't question his

knowledge), I offer this reply;  "Training and experience are the key to safe
and enjoyable diving, and knowing  "****" about diving is not my personal
approach.  .......   I think this is probably more important to fertilizer
salesmen  than to the issue of NITROX."

I'm sorry to indulge in stupidity, but that reply was particularly abusive
and it was nothing by character assassination. <PLEASE DON'T WASTE MY TIME
WITH ABUSIVE MAIL.  -THIS INCLUDES THE,  "IF YOU WERE MORE OF A MAN YOU WOULD
SEE IT MY WAY" mail.>  To those of you who wrote intelligible letters, thanks
but why not post them to the network?  If you are talking fact don't be afraid
to post!

------------------------Good Stuff------------------------------------------

I am not a NITROX diver.  I have read some articles on the technical aspects
of it, but remain some what a novice to the organized classes that are being
taught.  Could one(1) person take a moment and currently define, what is being
taught; (ie: depth considerations, oxygen toxicity,  what tables/saturation
model is being used, what sampling procedures are required,  what is the
allowable margin of error in gas concentrations and what is the current
requirement to recieve certification.

After this has been completed I think the opposition should intelligibly
and articulately state their case.
<-------Please refrain from name calling and name dropping---------------->
    -ie.  SeALs, Special Forces, and Commercial Divers are all trained
       at a different type of diving for a different purpose and to refer
       to their protocols is comparing apples to oranges.

I hope that we can as a diving community, learn about and discuss NITROX
intelligbly.

-And please if you must send me trash mail then please premark it:
  "NITROX-Hate Mail" that way I won't bother reading it- I'll just
    forward it to rec.scuba so others can laugh at your ignorance!
    Inteligent mail is always welcome.

Please let me know if any of you would be interested in having a discussion
of this at "Our World Underwater" in May.  I will contact them and see if it
would be possible if there is any interest.
-matt
MATT HUNSAKER   ~~~~~~~~~___100       ..            __  |__
DIVING RESEARCH GROUP        ___200  >->O      . .__L L_|L L__
HOME OF THE SPORTSMAN 300 MINISUB___300FT   . .[+(____________)
E-MAIL:U61474@UICVM   (815)399-1615                _________/
STUDENT, U OF IL COLLEGE OF MEDICINE
Newsgroups: rec.scuba