Shenzhen ZhongNuo Testing Technology Co., Ltd. specializes in the calibration, verification, and measurement services for gas alarms, combustible 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.
Verification Method
Appearance and structure
Inspect visually and by touch according to the requirements of section 4.1
Logos and Branding
Inspection to be conducted in accordance with requirement 4.2 by visual means.
Power-on Inspection
Inspect visually and by touch according to the 4.3 requirements to check the 5.3.4 alarm function and alarm action values.
Introduce a standard gas substance with a 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 at the time of alarm. Repeat the measurement three times, with the arithmetic mean of the three readings being the instrument's alarm action value.

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

What types of gas detectors require regular calibration and verification?
Fixed-installed, handheld, portable gas alarms, gas detectors, toxic and harmful gas detectors/alarm systems, flammable gas detectors/alarm systems, gas analyzers, etc.

Measurement Instrument Control
Instrument control includes calibration, subsequent calibration, and in-service 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 alarm instruments, offering regular inspections, metrological measurements, and calibration services. We hold the necessary qualifications to assist clients in solving fire and explosion prevention issues.