Calibration; Fresh Air Setup And Zero Calibration - MSA ALTAIR 4X Operating Manual

3.9 Calibration

• For 30 C.F.R. Part 75 determinations (MSHA versions), the ALTAIR
4X Multigas Detector must be operated in the 0-5% by volume
CH 4 mode and must be calibrated with 2.5% by volume methane.
The ALTAIR 4X can be calibrated manually using this procedure or
automatically using the Galaxy Test Stand. Refer to 7.7 of the Appendix.
Calibration must be performed using a flow regulator with a flow rate set
to 0.25 liters per minute.
If a battery charging cycle is interrupted before it is completed (4 hours
for a fully discharged battery), allow the instrument's internal
temperature to stabilize for 30 minutes before performing a Calibration.
NOTE: The Galaxy Test Stand is not a CSA certified calibration method.

3.9.1 Fresh Air Setup and Zero Calibration

To skip the ZERO procedure and move directly to the calibration span
procedure, push the ▲ button. If no button is pushed for 30 seconds,
the instrument prompts user to perform a SPAN calibration before
returning to the Normal Operation mode.
1. Press and hold the ▲ button in Normal Operation mode for three
seconds.
2. If calibration lockout option is selected, enter password.
• ZERO screen displays.
If calibration lockout option is NOT selected:
• ZERO screen displays.
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