097: Gas detector calibration and maintenance procedure

Gas detectors must be maintained on a regular basis. To maintain a gas detectors, we must follow the below steps for each detector:

1- Visual inspection: check the connections and screws, possibilities of crack, wear, rust, water and dust penetration and any damage.

2- Conduct a bump test or perform calibration (if required by schedule):

1. A) Expose the sensor to gas in a short time (bump test) to verify the sensor response and alarm functioning. The amount of gas should be less than the calibration gas.

Note1: If monthly bump tests result is not acceptable or more than 6 months have passed since the last calibration date, calibration should be performed.

1. B) Calibration of a gas detector means exposing of its sensor to a certified concentration of gas within a specified time. Calibration enables the detector to function properly and conduct accurate detection. Typically gas detector is calibrated once after production. But when has been put into operation, it must be calibrated at specified time intervals as a maintenance.

Calibration steps:

• Zeroing: First detector must recognize the ambient air (zero air).
• Procure suitable calibration kit including proper calibration adapter.
• Provide calibration gas cylinder.
• Expose the gas to sensor according to manufacturer's instructions.

3- Record the result

Related standards:

• BS EN 60079-29-2