Vyaire MicroLab Operating Manual page 71

Note: The MVV test is an exhausting test.
It should not be repeated without a rest
period. Some elderly or ill people cannot
repeat this test even after the rest period.
'Touch' Back to return to testing and the
current maneuver.
Note: If the breathing rate is insufficient
(less than 65 breaths per minute) then
the BR value will be displayed in red –
an MVV value will be calculated and a
message displayed that the MVV result
was extrapolated from a maneuver with a
poor breath rate.
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