rEvo Rebreathers rEvo III micro FT Use And Maintenance Manual page 23

Manual rEvo III
time you have doubts if the orifice is properly functioning (and you do not have access
to a flow meter). In case of an obstructed orifice the time-interval needed to drop
down the pressure would be much longer. If the flow rate is too high, that time-
interval would be much shorter!
The orifice can easily be changed: it simply unscrews. After replacing the orifice you
must be careful to always check the flow rate!
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