Shenzhen ZhongNuo Testing Technology Co., Ltd. specializes in the calibration, certification, and metrological services for gas alarms, flammable gas detectors, toxic and harmful gas detectors, and other equipment in various locations. We provide nationwide services to address electrical safety and explosion-proof fire prevention issues for our clients, contributing to safe production.
Gas Alarm Meters Calibration Conditions and Requirements
Environmental Conditions
Ambient Temperature: 0~40℃.
Relative Humidity: ≤85%
3. The working environment should not interfere with the normal operation of the instrument by electromagnetic fields or interfering gases.
Calibration Tools and Instruments
1) Certified Reference Gases
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: Resolution 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 piping that does not affect the concentration of the tested gas, such as polytetrafluoroethylene or stainless steel piping.

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

Verification Method
Appearance and structure
Inspect visually and by touch according to the requirements of Section 4.1.
Branding and Identification
Inspect as per requirement 4.2.
Power-on inspection
Inspect visually and by touch, in accordance with 4.3 requirements, to check the 5.3.4 alarm function and alarm action values.
Introduce a standard substance of gas at a concentration higher than the alarm set point, causing the instrument to trigger an alarm. Observe if the instrument's audio-visual alarm functions properly and record the reading at the time of the alarm. Repeat the measurement three times; the arithmetic average of the three readings is the instrument's alarm trigger value.

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 detectors generally does not exceed one year. This means that under normal circumstances, a comprehensive calibration and testing of the flammable gas detectors should be conducted annually to ensure their performance meets the relevant requirements.
Shenzhen Zhongnuo Testing Technology Co., Ltd. is an independent third-party service provider specializing in electrical safety, electrical explosion-proof, gas alarm, and toxic gas detection instrument calibration, verification, and measurement services. We are qualified to address fire and explosion prevention issues for our clients.