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Path: utzoo!linus!philabs!cmcl2!seismo!hao!nbires!opus!atkins
From: atkins@opus.UUCP (Brian Atkins)
Newsgroups: net.rec.scuba
Subject: Re: Results of general information request...
Message-ID: <1208@opus.UUCP>
Date: Fri, 17-May-85 15:34:11 EDT
Article-I.D.: opus.1208
Posted: Fri May 17 15:34:11 1985
Date-Received: Mon, 20-May-85 04:02:53 EDT
References: <2058@decwrl.UUCP> <10508@brl-tgr.ARPA> <5350@tektronix.UUCP>
Reply-To: atkins@opus.UUCP (Brian Atkins)
Distribution: net
Organization: NBI,Inc, Boulder CO
Lines: 35
Keywords: ScubaPro, Mark VII


With respect to the Mark VII first stage from ScubaPro, I would suggest
against it.  The Mark VII's main selling point is the fact that it's
audible.  The problems with it include the size, huge, the fact that it does
not rotate, making set up, storage, and many hose usage a real problem.

The primary fact that I don't like it is, aside from the inconvenience
of the shape/design, that you shouldn't rely on such a device.  You
should have a gauge that has been checked recently and is in general
trust worthy.  You should look at it frequently, especially under
conditions you're not used to (depth, diving at altitude, etc.).  It 
should be obvious when it fails.  If you have been at 40 feet for 20 
minutes, and the gauge reads much higher (or lower) than your normal 
consumption under the conditions would allow, you should be suspicious.  
If it is off by just a small amount, not enough to make you worried about
your gauge, then your end of dive reserve (300psi or so at least) should
keep you safe.  If you are ever in doubt, go up and get it checked.

In short, if you ever hear an audible without almost anticipating the
first clang (or breath out on a J-valve without anticipating that), you
should NOT be in the water at all!

One side note. A friend of mine just got back from Cancun.  He was on
a dive with a local guide when he was tapped on the shoulder.  The GUIDE
was there in a rather bad way since he was completely out of air!!  I guess
he took an empty tank with just a J-valve. The pressure was just enough to let
him get to depth before he ran out.  Unfortunately, his reserve was what he just
ran out of. Whether the J-valve was down when he set up, or it fell down
later, Luckily, my friend has an octopus.  Buddy breathing with someone
like that would not be a casual experience!

Has anyone else heard this kind of stuff?  Especially from Cancun/Cosumel?

Brian Atkins   ...{attunix, hao, allegra, ucbvax}!nbires!atkins
NBI Inc., P.O. Box 9001, Boulder CO 80301	(303) 444-5710