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 in various locations. We hold the necessary qualifications to serve nationwide, addressing clients' electrical safety and explosion-proof fire prevention concerns, and contributing to safe production.
The principle of instrument detection mainly includes catalytic combustion, infrared absorption, and thermal conductivity types. The sampling methods include diffusion and aspiration. The instrument is mainly composed of detection elements, amplification circuits, alarm systems, and displays, used for monitoring the concentration of combustible gases in the environment.

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; alternative substances like isopropanol can also be used. If the instrument does not specify the type of gas being measured, the concentration of the gas at the set point should be approximately 60% of the full scale, using a standard substance. The uncertainty of the expanded gas standard substance is not significant (%). The flow rate indication error of the repetitive dilution device should not exceed 0.%. The concentration unit of the dilution gas standard substance should be converted to match the unit of the inspected instrument, and the discrepancy should not be greater than 0.%.

Regular inspection contents for gas alarm detectors
Installation spacing of inspection (testing) points
2. Installation Height of the Detector
3. Indication Error (Concentration)
4. Repeatability (Concentration)
5. Alarm Error (Concentration)
6. Response Time (seconds)

Gas Detector Alarm Calibration Specification Requirements
Regulation 5.5 of the "Regulation for Calibration of Combustible Gas Detectors" (JJG693-2011) stipulates: The calibration cycle for combustible gas detection and alarm instruments: Generally, the calibration cycle of the instrument shall not exceed one year. Instruments with suspected measurement data, instruments that have replaced major components, or those repaired should be sent for calibration promptly.
Section 3.5 of "Regulations for the Use of Combustible Gas Detection and Alarm Systems" (SY6503-2000) stipulates: The combustible gas detection and alarm systems in use shall be calibrated regularly as required.
Occupational Health Service (GBZ/T223-2009) Article 7.2.1 stipulates: Calibration of detection and alarm devices shall be carried out regularly in accordance with the manufacturer's specified time and procedures.
Section 3.4 of the "Regulations for the Use of Combustible Gas Detectors" (SY6503-2000) states: Combustible gas detectors for installation and use shall have measuring instruments manufactured by an institution recognized for their**explosion-proof performance**.
Shenzhen ZhongNuo Testing Technology Co., Ltd. is a third-party institution specializing in electrical safety, electrical explosion-proof services, including regular inspections, metrological measurements, and calibrations for gas detectors and toxic/hazardous gas alarm instruments. We are qualified to provide solutions for fire and explosion prevention issues for our clients.