Shenzhen Zhongnuo Testing Technology Co., Ltd. specializes in the certification, calibration, and metrological services for gas alarms, combustible gas detectors, toxic and harmful gas detectors, and other equipment in various facilities. With qualifications to serve nationwide, we address a range of electrical safety and explosion-proof fire prevention issues for clients, contributing to safe production.
Which gas detectors require regular calibration and verification?
Fixed installation, handheld, portable gas detectors, gas alarm instruments, toxic and harmful gas detectors/alarm systems, flammable gas detectors/alarm systems, gas analyzers, etc.

Gas Alarm Meters Calibration Conditions and Requirements
Environmental Conditions
Ambient Temperature: 0~40℃.
2. 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) Certified Reference Gases
The relative expanded uncertainty of the gas standard substance does not exceed 2% (k=2).
2) Standard Gas Dilution Unit: Dilution Error of 1%
3) Stopwatch: graduation not greater than 0.1s.
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 Reducing Valve: A pressure reducing valve that matches with the calibrated cylinder.
7) Gas Pipeline: Tube for gas pipelines, such as polytetrafluoroethylene or stainless steel pipes, that do not affect the concentration of the measured gas.

Gas Standard Material
The gas standard substances used should be of the same type as the gas measured by the instrument, such as methane or other gases. If the instrument does not specify the type of gas being measured, the concentration of the gas, such as methane, with a set point increase of 60% is approximately the concentration of the standard substance at full scale. The uncertainty of the expanded gas standard substances is not more than % (k-body standard substance greater than ±1%). The flow indication error of the repeatability dilution device should not be higher than the concentration of the gas standard substance. The concentration unit of the dilution device for gas standard substances should be converted to the same unit as the measuring instrument when in use, and the value should not exceed 0.%.

The instrument's detection principle primarily 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 an independent third-party institution offering services such as periodic certification, measurement, and calibration for electrical safety, electrical explosion-proofing, gas alarms, and toxic and harmful gas detectors, as well as资质 to address fire and explosion prevention issues for clients.