Shenzhen ZhongNuo Testing Technology Co., Ltd. specializes in the calibration, verification, and measurement services for gas alarms, flammable gas detectors, toxic and harmful gas detectors, and other equipment at various locations. We hold the necessary qualifications to serve nationwide, providing solutions to electrical safety and explosion-proof fire prevention issues for our clients, and contributing to safe production.
Combustible Gas Detector Alarm Regular Inspection Content and Methods
Annual inspections are conducted on the sensors of commercial and industrial alarm systems, primarily checking for the accuracy, repeatability, drift, and response time of the alarms to ensure they meet standards. Additionally, the suitability of the alarm installation location and any interference from other equipment are assessed.

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) Gas Standard Material
The relative expanded uncertainty of the gas standard material does not exceed 2% (k=2).
2) Standard Gas Dilution Device: Dilution error of 1%.
3) Stopwatch: The least count is not greater 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 Reducing Valve: A pressure reducing valve that matches with the calibrated cylinder.
7) Gas Pipeline: Use gas lines made of materials like polytetrafluoroethylene or stainless steel that do not affect the concentration of the measured gas.

Standard for certification and metrological calibration of flammable and toxic gas detectors:
Standard for Design of Detection and Alarm Systems for Combustible and Toxic Gases in Petroleum and Chemical Industry - GB/T50493-2019
GB12358-2006 General Technical Requirements for Environmental Gas Detection and Alarm Instruments in Workplace
JJG693-2011 "Regulation for Calibration of Combustible Gas Detectors"

Measurement Instrument Control
Instrument control includes calibration, follow-up calibration, and in-use inspection.
Shenzhen Zhongnuo Testing Technology Co., Ltd. is a third-party institution specializing in electrical safety, electrical explosion-proofing, gas alarm systems, and toxic and harmful gas detection instruments. We offer regular inspections, metrological services, and calibrations. We are qualified to help customers address fire and explosion prevention issues.