WHY WE DO NOT BOUNCE DIVE AFTER DIVING IN THE WKPP

It is ok to offgas from the tissues into the blood stream in bubble form in
the later steps of decompression as it is a more efficient, faster way of
getting rid of the remaining gas ( by reduced pressure ) than by elevated
oxygen alone ( which starts taking exponentially more time with greater
risk)  . However, this depends on having a good lung filter and no shunts.
All of you  have been PFO tested if you are diving with us.

The correct way to ascend from the last stop is one foot per minute for the
bigger dives.

The greatest potential for offgassing in bubble form is when the pressure is
totally removed back to one ATA out of the water. Now you get a real shower
of  bubbles , relative to what was happening in the water. A good , clean
deco  with the foot per minute ascent reduces this dramatically .

In MOST people, the greatest bubbling occurs out of the water and continues
for up to four hours, not even peaking for a couple of hours. In a well
vascularized, fit person like me, it is over with in 30 minutes. Don't bet
on  that with most of you.

In ALL people, the bubbles continue to grow in size after the pressure is
off.  They accumulate like gas into themselves from the surrounding blood or
tissues  ( if there are bubbles in the tissues or injury sites ) and they
grow bigger.  This is why you feel pain later rather than earlier if the
bubbles are in  joints or tissues - they get bigger before they begin to
shrink. This is why  what starts out as micro bubbles can get by the lungs
and grow and get lodged  downstream, and you get neurological symptoms
later.

Now here is the important part. If you understand everything I have said
above, then you know that bouncing to 20 feet or whatever to pick up a
bottle  and immediately returning to the surface is the like giving yourself
a  home-made PFO: the bubbles in the venous side compress enough to get past
the  lungs and then will reexpand on the arterial side and lodge in the
worst  places , the spine and brain blood supplies. You do not want this.

If you dive after dive, stay down and let everything reset. Get the bubbles
all compressed, and then deco out and ascend accordingly.

I do not want support divers diving support within four hours of doing a
real  dive or deep support. This works out fine, since we have support
activities  lasting up to 18 to 24 hours and need to rotate everyone.

Let me assure you that we have found this out the hard way in the past.
Parker  used to get hot as hell when it would happen. In those days we had
"volunteers", and they would all get bent diving to 20 feet to pick up
bottles. We have also seen some severe cases of this where dives were done
away from the project with no support, and the players went back for bottles
later and got hammered.

Don't do it. Also, obviously, do not freedive after a dive. When you want to
freedive, do that first and then go scuba diving.

Any questions from WKPP guys?

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