MSA ALTAIR 4XR Operating Manual page 36

• If calibration lockout option is NOT selected:
ZERO screen displays.
(3) With the device exposed to fresh air, press the
q button to confirm the ZERO CAL? screen. A
sensor refresh and Zero Calibration will occur.
Alternatively press the  button to execute a Fresh Air setup (FAS). See chapter 3.2
"Turning ON and Fresh Air Setup" for more details.
After Zero calibration completes, the device momen-
tarily displays "ZERO PASS" or "ZERO ERR" along
with the flag of any sensor that failed.
During zero calibration the O
adjusting the calibration curve as needed. During span calibration, the O
racy is checked against a known oxygen gas concentration without adjusting the calibra-
tion curve.
sensor is also span calibrated to 20.8% O
2
®
ALTAIR 4XR
Operation
fresh air,
2
sensor's accu-
2
36
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