Shenzhen Zhongnuo Testing Technology Co., Ltd. specializes in the calibration, verification, and measurement services for equipment such as gas alarms, combustible gas detectors, and toxic gas detection instruments for various locations. We hold qualifications to serve nationwide, addressing clients' electrical safety and explosion-proof fire prevention concerns, and contributing to safe production.
Gaseous Detector Alarms Calibration Standard Requirements
Section 5.5 of the "Regulation for Calibration of Combustible Gas Detectors" (JJG693-2011) stipulates: The calibration period for combustible gas detection and alarm instruments: Generally, the calibration period of the instrument 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 calibration promptly.
Section 3.5 of the "Regulations for the Use of Flammable Gas Detection and Alarm Systems" (SY6503-2000) stipulates: Flammable gas detection and alarm systems in use shall be calibrated regularly as required.
Occupational Health Services - Technical Specification for Installation of Toxic Gas Devices in Workplaces (GBZ/T223-2009) Article 7.2.1 stipulates: Calibration of detection and alarm devices should be performed 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**.

Regulatory Content and Methods for Regular Flammable Gas Detector Inspection
Annual inspections are conducted on the sensors of commercial and industrial alarms, primarily checking for the accuracy, repeatability, drift, and response time of the alarms to ensure they meet standards. Additionally, the suitability of the alarm's installation location and any interference from other equipment are assessed.

Power-on inspection
After powering on the instrument, it should operate normally with clear and complete display. Check the alarm function and the alarm trigger values.
Alarm function and alarm action value verification
The instrument's acoustic and visual alarm should be functioning normally. Insulation resistance
Insulation resistance for equipment using AC power should not be less than 20MΩ.

Verification Method
Appearance and structure
Inspect visually and by touch according to the requirements of Section 4.1.
Logos and Branding Marks
Inspection to be conducted in accordance with requirement 4.2 by visual means.
Power-on Inspection
Inspect visually and by touch in accordance with the requirements of 4.3 to check the 5.3.4 alarm function and alarm action values.
Introduce a standard substance of gas with a concentration exceeding the alarm set point, causing the instrument to trigger an alarm. Observe if the instrument's sound and light alarm functions properly and record the instrument's reading when the alarm is triggered. Repeat the measurement three times, and the arithmetic mean of the three readings is 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 alarm systems, and toxic and harmful gas detectors for regular inspections, metrological measurements, and calibration services. We are qualified to address fire and explosion prevention issues for our clients.