Shenzhen ZhongNuo Testing Technology Co., Ltd. specializes in the calibration, certification, and metrological services for gas alarms, combustible gas detectors, and harmful gas detectors for various locations. We serve nationwide, providing solutions for electrical safety and explosion-proof fire prevention issues, and supporting safe production.
GAS ALARM METER CALIBRATION CONDITIONS AND REQUIREMENTS
Environmental Conditions
Ambient Temperature: 0~40℃
Relative Humidity: ≤85%
3. The working environment should not affect the normal operation of the instrument with electromagnetic fields and interfering gases.
Calibration Tools and Instruments
1) Gas Standard Material
The relative expanded uncertainty of the gas standard substance is not greater than 2% (k=2).
2) Standard Gas Dilution Unit: Dilution Error of 1%.
3) Stopwatch: The least count should not be more than 0.1 seconds.
4) Flow Control: Flow range not less than 500 mL/min, flow grade not less than level 4.
5) Zero Point Gas: Purified compressed air.
6) Pressure Relief Valve: A pressure relief valve that matches with the calibrated cylinder.
7) Gas Pipeline: Tubing made of materials such as polytetrafluoroethylene or stainless steel that do not affect the concentration of the gas being measured.

Power-on inspection
Upon power-on, the instrument should operate normally with clear and complete display sections. Check the alarm function and alarm trigger values.
Alarm function and alarm action value verification
The instrument's audio-visual alarm should be functioning normally. Insulation resistance
Insulation resistance for instruments using AC power should not be less than 20MΩ.

The calibration cycle for flammable gas detectors is typically once a year.
In accordance with the standard JJG 693-2011 "Flammable Gas Detectors," the calibration cycle for flammable gas alarms generally does not exceed one year. This means that, under normal circumstances, a comprehensive calibration and test of the flammable gas alarm is required annually to ensure its performance meets the relevant requirements.

The principle of instrument detection mainly includes catalytic combustion, infrared absorption, and thermal conductivity types. Sampling methods include diffusion and aspiration. The instrument is mainly composed of detection elements, amplification circuits, alarm systems, and displays, used for monitoring the concentration of combustible gases in the environment.
Shenzhen ZhongNuo Testing Technology Co., Ltd. is a third-party institution specializing in electrical safety, electrical explosion-proof, gas alarm, and toxic and harmful gas alarm instrument calibration, metrological verification, and regular inspections. We are qualified to provide solutions for fire and explosion prevention issues for our clients.