Welch Allyn PneumoCheck Operating Instructions Manual page 13

Unacceptable conditions include:
slow or hesitating start
l
air leaking around the mouthpiece
l
coughing during the first second of the maneuver
l
mouthpiece obstruction by tongue, lips, or teeth
l
quitting too soon
l
6. When the maneuver has been completed, observe the quality
message. If a message appears indicating an unacceptable
maneuver (see p. 49), instruct the patient on how to correct the
problem and repeat the test.
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