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5. Secure gas cylinder to a wall, bench or stand with a mounting bracket so it will not
tip over or fall.
6. Observe the inlet supply pressure gauge, which will verify cylinder pressure.
PURGING THE GAS DISPENSER
: Purging air from the gas dispenser should be done
each time a new tank of calibration gas is installed and prior to instrument calibration.
1. Open the regulator's valve and observe 5 to 10 inches of water column pressure on
the gas dispenser's gauge.
2. Leaving the regulator's valve open insert the tip of the detector's extended standard
probe as far as it will go into the outlet on the front panel of the gas dispenser.
3. Switch to the % LEL scale and wait several minutes. The % LEL reading will
slowly climb to a maximum and stabilize.
4. When finished purging close the regulator's valve.
CALIBRATING DETECTORS
1. Calibrate gas detectors following the procedure for A-CAL calibration (Part 2,
Section 1).
2. When finished calibrating close the regulator's valve.
