Shenzhen ZhongNuo Testing Technology Co., Ltd. specializes in the calibration, verification, and metrological services for gas alarms, combustible gas detectors, and toxic gas detection instruments for various locations. We hold the necessary qualifications to serve nationwide, addressing electrical safety and explosion-proof fire prevention issues for our clients, and contributing to safe production.
Gas alarm detector regular inspection content
Installation spacing of inspection (probe) points
2. Installation Height of the Detector
3. Indicated Error (Concentration)
Repeatability (Concentration)
5. Alarm Error (Concentration)
6. Response Time (seconds)

Gas Alarm Meters Calibration Conditions and Requirements
Environmental Conditions
Ambient Temperature: 0~40℃
2. Relative Humidity: ≤85%
3. The working environment should not interfere with the normal operation of the instrument due to electromagnetic fields and interfering gases.
Inspection Gauges and Instruments
1) Standard Gas Material
The relative expanded uncertainty of the gas standard material is not greater than 2% (k=2).
2) Standard Gas Dilution Device: 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: Tubing made of materials like polytetrafluoroethylene or stainless steel, which do not affect the concentration of the measured gas.

GB 12358-2024 "General Technical Requirements for Environmental Gas Detection and Alarm Instruments in Workplace" is an important standard.
Intended to standardize the performance, functions, and testing methods of environmental gas detection and alarm instruments used in workplace operations.
The standard was published in 1990 and has undergone several revisions.
The new version is GB 12358-2024, which will be officially implemented on June 1, 2025.
This standard applies to the production and use of gas detection and alarm instruments for flammable gases, toxic and harmful gases, and oxygen in workplace environments.

Gas Standard Material
We use gas standard substances of the same type as the measured gas by the instrument, such as methane or ethane, or gas standards can also use isopropanol, etc. If the instrument does not specify the type of gas being measured, the concentration of the gas, such as methane, ethane, or报警设定点的气体, is approximately 60% of the full scale. The uncertainty of the standard gas concentration is not more than % (for gas standard substances greater than ±1%), and the flow indication error of the repeatability dilution device should not be greater than 0.%. The concentration unit of the dilution device for standard gas substances should be converted to match the unit of the tested instrument, and the discrepancy should not be more than 0.%.
Shenzhen ZhongNuo Testing Technology Co., Ltd. is a third-party service provider specializing in electrical safety, electrical explosion-proofing, gas alarm systems, and toxic/hazardous gas detection equipment, offering regular inspections, metrological measurements, and calibrations. We hold the necessary qualifications to assist customers in addressing fire and explosion prevention issues.