Welch Allyn PneumoCheck Operating Instructions Manual page 54

RETRYCAL
TOO.SHORT
WEAK TRY
One or more of the calibration maneuvers differed
from the average by more than 0.5%. The existing
calibration factor is not updated.
the maneuver was less than 3 seconds
During FVC:
long. The patient should inhale more deeply and
exhale longer.
The maneuver was less than 6
During MVV:
seconds long. The patient should continue longer.
Low flow effort. To correct this, the patient should
blast out harder.
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