Bill,
I don?t know the
exact reasoning why it works but anecdotal evidence from the Woodhill Karst
Plain Project (WKPP) deep, long dives, other major arduous diving projects,
and discussions with Dr. Bill Hamilton support this conclusion. Can?t
remember exactly but believe that there has been some formal research also
where divers were monitored ultrasonically for bubble formation. While
this doesn?t necessarily conform to our historical models for decompression,
the tech diving community has definitely pointed out that our Haldanian
approach to deco is wrong. Slower descent, deeper stops, and the use of
O2 over the last 15 years has drastically cut the amount of deco
required and lowered the incidence of deco hits.
The micro-bubble
release on subsequent dives (not only bounce dives) was noted by the oil
companies while conducting saturation diving research but wasn?t really
released to the public until the early 80s. It took into the early-90s
for it to become common knowledge in the tech diving
community.
R/Jay
From:
owner-personal_submersibles@psubs.org
[mailto:owner-personal_submersibles@psubs.org] On Behalf Of Akins
Sent: Saturday, March 11, 2006 2:08
PM
To: personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST] manned
torpedo
That did indeed answer my original
questions, and excellently so. Thank you very much.
I do have a few dive questions
about number 2 that you listed. You said....."Bounce dives to deeper depths are an animal unto
themselves.
Recent experiences in
the tech diving world points out that a slower descent is more advantageous
for the subsequent decompression regime
followed during
ascent (note that all dives are decompression dives as our ascent rate on
supposed no-deco dives is there to allow elimination of absorbed gases).
Additionally, it has
been shown through laboratory hyperbaric experimentation that a bounce dive
after a previous dive should be avoided as the rapid pressurization
and depressurization
causes a large quantity of micro-bubbles to be released and this is very
undesirable."
I am curious how descending more
slowly would be more advantageous for the subsequent decompression regime that
as you pointed out is done on all non
deco
dives by our ascent rate? I
don't understand how this can be. If you decend more slowly you have more time
for nitrogen to saturate your tissues, so how
would
decending more slowly
and therefore having more time for nitrogen to saturate your
tissues, be advantageous in any way for your decompression regime on
ascent?
Wouldn't this mean your bounce
dive would become a more saturated dive and therefore possibly need more deco
time which is exactly what you were trying to
avoid
by doing the "bounce" dive in the
first place?
I do know that a bounce dive
after a previous dive without total and complete offgassing is not a good idea
for the micro bubble reasons you stated.