G'day Steve,
On 04 March 1997 you were in deep conversation with Cato Landsvik
CL>Or do like me: exhale air automatic (I have a vent in my
CL>mask) :) Then you don't have that problem ever.
 SE> That's true.  There are some masks still on the market with
 SE> a purge valve down below the nose pocket.  Exhaling through
 SE> the mask would relieve the pressure.
The purge valve at the bottom of the mask is so that water can be
drained out without usuing the usual method of holding the top
facing up a bit and breathing out through the nose.
Problem with purge valves is they tend to leak. [:}O-
Alan
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