One is to verify the environmental conditions. As it is an electronic instrument, the errors in its calibration mainly come from the calibration environment:
1. Require good ventilation.

2. No interference with the tested components.

3. Environmental temperature.
The second is to verify flow control.

During the verification process, as combustible gas detectors are mostly catalytic combustion sensors, the flow rate directly affects the accuracy of the verification results. The alarm can only maintain high sensitivity within a certain flow range, and being too high or too low can have a significant impact on sensitivity. When the flow rate is less than the measurement requirement, the surface of the sensor component will not reach the true concentration, and the combustible gas will not be replenished in a timely manner after combustion, and the combustion cannot continue, so the sensitivity is very low. As the gas flow rate increases, the thermal effect correspondingly increases, and the sensitivity gradually increases. When the gas flow rate continues to increase, the excessive airflow will increase the heat dissipation of the component, which in turn reduces the sensitivity. When the flow rate exceeds the measurement requirements, the accuracy decreases. Generally, when designing instruments, manufacturers have already selected the gas flow rate through repeated experiments. When the gas flow rate is very low, a bypass flowmeter must be used to calibrate the suction alarm, otherwise it may cause inaccurate calibration results.
The third issue is that the readings of the main controller and the on-site detector do not match during calibration.

The combustible gas alarm is connected by a separate line system between the main controller and the detector. The detectors are distributed at multiple monitoring points, and the main controller centrally controls them. The gas concentration of each detector is independently displayed. When the gas concentration of the detector in the environment reaches or exceeds the preset alarm value, the main controller will issue an alarm to remind the on duty personnel to take safety measures and ensure the safety production of the enterprise.