Shenzhen Zhongnuo Testing Technology Co., Ltd. specializes in the certification, calibration, and metrological services for equipment such as gas alarms, combustible gas detectors, and toxic gas detectors for various locations. We provide qualifications and services nationwide, addressing clients' electrical safety and explosion-proof fire prevention needs, and supporting safe production.
Standard for verification and calibration of combustible and toxic gas detectors:
GB/T50493-2019 "Design Standard for Detection and Alarm 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规程 for Calibration of Combustible Gas Detectors and Alarms

Regular inspection items for environmental gas detection and alarm instruments in workplace operations:
Alarm sound and light (if applicable)
2. Low response value
3. Indication Error (for Gas Detectors/Gas Detector Alarms)
4. Instrument Drift (in Portable Instruments)
5. Alarm Error (for Gas Detector/ Gas Alarm)
6. Pump-actuated instrument gas collection distance and flow rate (for pump-actuated instruments)
7. Power Supply (for battery-powered instruments)
8. Response Time
9. Status Indicator (with wireless communication function)

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

Appearance and structure
The instrument should not have any appearance damage that affects its normal operation. The surface of newly manufactured instruments should be smooth and glossy, with an even paint and plating layer, and no signs of peeling or rusting.
The instrument's connections are reliable; all knobs or buttons should operate and control normally.
Logos and branding
Instrument name, model, manufacturer's name, date of manufacture, serial number, explosion-proof marking and number, as well as the manufacturing measurement instrument license marking and number of domestically manufactured instruments should be clear.
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 for regular inspections, metrological measurements, and calibrations. We provide资质 to address fire and explosion prevention issues for our clients.