From: dave@hpdstma.ptp.hp.com (Dave Waller)
Newsgroups: rec.scuba
Subject: Re: PEEING IN A WETSUIT
Date: 28 Aug 92 17:08:39 GMT
Article-I.D.: scd.BtpEAG.41r
Organization: Hewlett Packard

In article <1992Aug28.145024.1388@mksol.dseg.ti.com>, pyron@skndiv.dseg.ti.com (Dillon Pyron) writes:
|> 
|> In article <92240.215804FKK@SLACVM.SLAC.STANFORD.EDU>, FKK@SLACVM.SLAC.STANFORD.EDU writes:
|> >Many of us have known that brief surge of warmth from peeing in
|> >our wetsuits.
|> >
|> >Since I now dive dry I monitor my fluid intake carefully before
|> >diving to avoid this problem but...
|> >
|> >A friend recently told me that due to a change that takes place
|> >in your skin after contact with urine, you lose heat more rapidly
|> >after peeing in your suit.  Does anyone confirm this?
|> >
|> You have lost a lot of heat when you pee.  You are dumping a quantity of liquid 
|> which is at body temperature.  And you're not likely to regain those calories
|> anytime soon.  I don't know about the skin contact thing.

I would conjecture that this is inconsequential, for two reasons: The bladder,
when emptied, looks basically like a collapsed flesh bag. Therefore, nothing
inside your body gets colder as a result of the expulsion of urine. Second,
relative to the volume of fluids in your body, a typical quantity of urine
is miniscule by comparison. Were you to take an amount of saline equivalent
to total body fluid ata temperature of 98.6F, and mix in a quantity of ice
water equivalent in volume to an average bladder, the temperature drop would
be very small.

My guess is that, view strictly from a thermal sense, the benefit that one
gets from the warm urine in their wetsuit more than compensates for any
cooling effect the removal of that urine from the interior might have, and
I am extremely dubious that it has any cooling effect at all, given the
physiology of the urine tract.

As for the effect of urine on the skin, this is the first I have ever heard
that urine might cause the skin to release heat more rapidly. Urea *is*
irritating to the skin, and as such would cause dilation of the surface
capillaries if the irritation became acute, however this requires lengthy
contact with rather concentrated urea before acute irritation occurs. Of
course, sensitivity to this is a very individual thing; certainly, someone
might be hypersensitive and have an allergic reaction to small amounts of
urea in contact with the skin for more than a few minutes. However, for most
people, this is not a big problem when occasionally relieving themselves
in a wetsuit.

I would add that, unless someone hasa bladder, kidney, or urinary tract
infection, urine is essentially sterile when it leaves the body and therefore
presents no infection risk. Of course, outside the body it quickly gets
contaminated, and will act as an excellent substrate for growing all kinds
of nasties. Therefore, if you are one of those divers who doesn't mind
urinating in your wetsuit, be sure and clean it very well after the dive.
I would suggest a regimen of vigorous washing in a 40-50 gallon plastic
garbage can, with two capfuls of Woolite added to the water as the can is
filling. Then, dump the wash water, refill the can with fresh water, and
rinse thoroughly. It's best if you repeat the rinse cycle at least once
with another barrel of fresh water.

Personally, I don't like to urinate in my wetsuit, so I don't. However,
I do implement the cleaning regimen for all my neoprene items (with only
one rinse, as I don't unrinate on any of them :-)), and I have made a
Moray wetsuit last five years and over 400 dives. It does finally need
replacement, however, due to crushing of the neoprene.


-- 
Dave Waller
Hewlett-Packard Co.
Workstation Systems Division
Sunnyvale VAB Consulting
(408) 746-5324
Newsgroups: rec.scuba