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Hi,

Jim Sibthorp asks;
I have a question which I hope someone on the net can answer. We
currently use bailout bottles connected to a DSI manifold block in one
of our redundant equipment configurations. Currently, all pony first
stages must be equipped with an over pressure relief valve from DSi at a
cost of $28 dollars per item. This is basicaly a spring loaded seat
which plugs into a lp port and allows pressure to be vented in case the
first stage pressure "creeps" above 200 psi, thus eliminating the
possibility of rupturing the low pressure hose which goes from the pony
first stage to the manifold block. I know we could add a second stage to
the pony reg, but this is a cumbersome option. Does anyone have a better
solution than forking out the $28.00 per set, or is this the best
option? How about the Sherwood dry bleed system. If a sherwood regulator
creeps, will this pressure be vented at an increased rate through the
dry bleed valve, or is this valve too small to ever be used as a safety
measure (I suspect it is, but would appreciate confirmation).
end quote.
Yes Jim you are doing the best thing already.  This is the setup used by
every commercial dive company I have seen and they never spend money they
don't have to.  The only other thing you could do in pressurize the line and
turn the bailout off at the bottle.  Not a perfect system.

Don't forget that you also need a nonreturn valve in the block so that
a rupture in your primary line doesn't cause the gas to escape when you go
to the bailout.

Cheers Jason :)

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