Shenzhen Zhongnuo Testing Technology Co., Ltd. specializes in the calibration, verification, and metrological services for gas alarms, flammable gas detectors, toxic and harmful gas detectors, and other equipment, serving a wide range of locations across China. We address various electrical safety and explosion-proof fire prevention issues, contributing to safe production.
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 Gas Standards
The relative expanded uncertainty of the gas standard material does not exceed 2% (k=2).
2) Standard Gas Dilution Unit: Dilution Error of 1%.
3) Stopwatch: Resolution not greater than 0.1s.
4) Flow Control: Flow range not less than 500 mL/min, flow grade not less than 4.
5) Zero Point Gas: Purified compressed air.
6) Pressure Relief Valve: A pressure relief valve that is compatible 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 tested gas.

Flammable and toxic gas alarm detectors verification and calibration standards:
Standard GB/T50493-2019 for the Design of Detection and Alarm Systems for Combustible and Toxic Gases in Petroleum and Chemical Industries
GB12358-2006 General Technical Requirements for Environmental Gas Detection and Alarm Instruments in Workplace
JJG 693-2011 "Code of Inspection and Verification for Combustible Gas Detectors"

Gas Detector Alarm Calibration Specification Requirements
Regulation 5.5 of the "Regulation for the Verification of Combustible Gas Detectors" (JJG693-2011) stipulates: The verification cycle for combustible gas detection and alarm instruments: the verification cycle for the instrument generally should not exceed one year. If there is any doubt about the instrument's measurement data, or if the instrument has been replaced with major components or repaired, it should be sent for verification promptly.
Section 3.5 of the "Regulations for the Use of Flammable Gas Detection and Alarm Systems" (SY6503-2000) stipulates: The flammable gas detection and alarm systems in use shall be calibrated regularly as required.
The Regulation of Toxic Gas Device Installation in Workplace (GBZ/T223-2009) Article 7.2.1 stipulates: Calibration of detection and alarm devices shall be carried out regularly according to the manufacturer's specified time and procedure.
Section 3.4 of the "Code for the Use of Combustible Gas Detectors and Alarms" (SY6503-2000) stipulates: The installation and use of combustible gas detectors and alarms shall have measurement instruments manufactured by an institution recognized for their**explosion-proof performance**.

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 work sites.
The standard was issued 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.
Shenzhen ZhongNuo Testing Technology Co., Ltd. is a third-party institution specializing in electrical safety, electrical explosion-proofing, gas alarms, and toxic gas detection instruments, offering regular inspections, metrological measurements, and calibration services. We are qualified to help customers address fire and explosion prevention issues.