Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84; site utcsri.UUCP
Path: utzoo!utcsri!sandler
From: sandler@utcsri.UUCP (Howard Sandler)
Newsgroups: net.rec.scuba
Subject: Re: Snorkels
Message-ID: <1572@utcsri.UUCP>
Date: Wed, 30-Oct-85 19:39:22 EST
Article-I.D.: utcsri.1572
Posted: Wed Oct 30 19:39:22 1985
Date-Received: Wed, 30-Oct-85 19:51:28 EST
References: <12000005@uiucdcs>
Organization: CSRI, University of Toronto
Lines: 23


  I don't think that the problem with wide-bore snorkels is "dead-
air" space.  The air you exhale into the tube is still 16% oxygen and
makes up only a fraction of the air you inhale on the next breath.  
The difficulty that I have found with wide-bore snorkels is the large
amount of water that drips back to the mouthpiece after clearing
them.  Perhaps this is ddue to the larger surface area compared to
a smaller-bore snorkel.  
     Having said that, I still prefer a wider snorkel for the easier breathing
resistance.  The rule I was taught in my NAUI course was to choose a
snorkel just wide enough to stick your thumb into.  It has never failed me yet.

     I would like to pose a question myself.  I have always used snorkels that 
bend immediately from the mouthpiec; that is, they don't have the classic
"J" shape that early snorkels had.  I find that after clearing these snorkels
the drip-back arrives right at my mouth, causing me to choke on the next
inhalation.  It seems to me that the true "J" -shaped snorkels would be
better, since the water would collect at the pit of the bend, rather than 
at the mouthpiece.  

                             Howard M. Sandler
                              Dept. of Electrical Engineering
                            University of Toronto