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	WRT the on going discussion; 

	There are two aspects to the tables we use, one is the numbers
giving stop times for dive depth/time combinations, and the other part
is the diving instructions that accompany those. For instance, according
to BSAC88 you can do 15min at 30m every four hours till the cows come
home, although most divers would agree that that is a little silly. So,
the tables include an instruction that you do no more than 3 dives a
day. Another instruction, much ignored, is to do no more than 20min of
stops per day...

	Other included instructions concern the ascent rate, and not
doing excercise directly after diving.

	We *all* suffer from bubbles after dives, and we can *all* find
ways of forcing these guys through into our arterial system. PFO makes
this easier. 

	We don't need a completely different set of tables, we just need
a set of instructions that can be given to divers who know that they
have PFO and to what degree.

	For instance - add a deeper stop for 3min?
		       add an extra 5min at 6m (3m for fine weather)?
		       add 5min 'surface stops' before exiting the
water, either onto shore or into a boat?
		       'suggesting' that PFO divers invest in an oxygen
kit (I don't know how seriously to suggest that, it seems a little
morbid).

	This is based on the idea that they need to be even more careful
to ensure that the bubble load is reduced before exerting forces on the
chest. I agree however that in the case of a PFO 'you can stick your
thumb through' the diver needs to think about why he is diving, and
perhaps try out wheelchair designs...

	On the whole though, although PFO does appear to carry an
increased risk of DCI, the majority of PFO divers still knock off a
couple of hundred dives before getting hits (based on the three DCS hits
I know of near to me, and a couple of written bits I can half remember).

	if 1/10000 is acceptable to most of us, is 1/1000 really so much
worse?

	I also tried fooling around with a compartment loading model and
was thrown by the variable critical ratios bit. I didn't graduate to a
real program though (or a computer) I just use tea-leaves to plan my
stops now. Much more exiting. :-)

	Jason.

	Who is young and immortal. Yeah right.

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