🚀 go-pugleaf

On a side note to the discussion on diving....
The problem with deep dives is that you have so little time on the bottom
that it's difficult to get much done.  A 130 foot dive from the surface
gives you about 5 minutes bottom time without a decompression stop, and
not much more even with decompression.
  One solution to this problem for people who need to work at depth (e.g.
marine scientists running experiments) was used for several years down in
St.Croix (pre-Hugo).  There was an underwater living space at about 50
feet depth and scientists would live there for a week while conducting
experiments.  (two people at my lab have done this)  The big advantage is
that diving from (and returning to) 50' depth, you get about 5 hours of bottom
time
without decompression problems.  Of course, this requires a lot of outside
assistance, ferrying down new full air tanks, etc, and the final ascent at
the end of the week is interesting... They put you in a pressurized ball
at depth, seal it, and take you up to the surface where you are placed in
a large (very comfortable) hyperbaric chamber, where they return you to
surface pressure... over eighteen hours!   The kicker is that after this,
you can't fly for 2 days or so, so you're trapped on a Caribbean isle for
a couple of days with doctor's orders to relax and take it easy!!
Of course, I don't know about how bad the nitrogen narcosis can get after
a week at depth..

Unfortunately, the underwater habitat was damaged by Hugo and I'm not sure
of its status now...

-- 
Jim Welch
University of Delaware
Graduate College of Marine Studies
jimwelch@ravel.udel.edu