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 for various locations. We offer services nationwide, addressing all types of electrical safety and explosion-proof fire prevention issues for clients, and contributing to safe production.
Gas Standard Material
The gas standard substance used should be of the same type as the gas measured by the instrument, such as methane, ethane, or other gases; gas standards can also be isopropanol, etc. If the instrument does not specify the type of gas being measured, the concentration of the gas at the set point of the alarm should be approximately 60% of the full scale, using a standard substance. The uncertainty of the expanded gas standard substance is not significant (%); the repeatability of the standard substance should be greater than 1%. The flow indication error of the dilution device should not be higher than the concentration of the gas standard substance. The concentration unit of the gas standard substance should be converted to match the unit of the instrument being tested when in use. The uncertainty should not exceed 0.%.

Measurement Instrument Control
Instrument control includes calibration, follow-up calibration, and in-service inspection.

Regular inspection items for environmental gas detection and alarm instruments in work场所:
Alarm sound and light (if applicable)
2. Low response value
3. Indicated Error (for Gas Detectors/Gas Detector Alarms)
4. Instrument Drift (in Portable Instruments)
5. Alarm Error (for Gas Detection Alarm / Gas Alarm)
6. Pump-suction Instrument Gas Sampling Distance and Flow Rate (for Pump-suction Instruments)
7. Power Supply (for battery-powered instruments)
8. Response Time
9. Status Indicator (with Wireless Communication Function)

Calibration Method
Appearance and structure
Inspect visually and by touch according to the requirements of Section 4.1.
Logos and Branding Marks
Conform to the requirements of Section 4.2 by visual inspection.
Power-on inspection
Inspect visually and by touch according to the requirements of 4.3 to check the alarm function and the values of alarm actions in 5.3.4.
Introduce a standard substance with a gas concentration exceeding the alarm set point, causing the instrument to trigger an alarm. Observe if the instrument's audio-visual alarm functions normally and record the instrument's reading when the alarm is triggered. Repeat the measurement three times, with the arithmetic mean of the three readings being the instrument's alarm trigger value.
Shenzhen Zhongnuo Testing Technology Co., Ltd. is a third-party institution specializing in electrical safety, electrical explosion-proofing, gas alarms, and toxic and harmful gas detection instruments for regular calibration, measurement, and verification services. We hold the necessary qualifications to assist clients in solving fire and explosion prevention issues.