Quote: (Originally Posted by
Gill Envy)
... how do you deal with the need to be able to flush to lower po2...hypoxic dilluent/BO stages?
It depends what flexibility you built into your rig. I, for e.g. have ADV (= BOV too) access and switch-ability for both on and off board tanks. I so far like use the following priority of considerations in my dive planning (not exactly like how I was trained, and has developed as a result of experience + Rebreather World discussion).
1) Always have safe gas to B/O to
2) Minimal but adequate B/O volume to get to surface
3) Low PO2 flushing
Priorities 1 & 2 tends to compromise 3. I can argue a net result and plan that is safer for many if not most circumstances.