This article describes how to calibrate G7 and G8 devices equipped with chlorine dioxide (ClO₂) sensors.

1. Attach tubing to the calibration cap and to the outlet of the gas generator.
   Important:

   The generator should set the appropriate flow rate; however, this may depend on the gas generator you are using. Always follow the instructions provided with your generator.

2. Press the OK button to display the Main menu.
3. Navigate to Gas options using the left and right buttons, then press OK.
4. Navigate to Calibration using the left and right buttons, then press OK.
5. When prompted, select Yes to start the calibration.
   The device performs a hardware self test of its lights, sound, and vibration.
6. Select the ClO₂ sensor, ensuring that any other sensors are not selected.
7. Use the left and right buttons to select Start span, then press the center button to start the calibration.
   The device starts a countdown from 60 seconds.
8. Attach the calibration cap to your device and apply the gas within this time window.
   The device automatically detects the gas and starts the calibration.
9. Turn off the gas when prompted, then press the center button to complete the calibration.

   The device displays a pass or fail message and when your next calibration is due.

10. Allow the residual gas to clear, then disconnect the calibration cap and let your device sit until the readings stabilize.
11. Gently wipe down the gas sensor cartridge with a cloth dampened in tap water to remove any ClO₂ on the cartridge surfaces.
    Note:

    To remove any ClO₂ gas residue from the cap, Blackline recommends rinsing the calibration cap after completing ClO₂ calibrations.