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 customers, and contributing to safe production.
Power-on inspection
After power is applied to the instrument, it should operate normally with clear and complete display. Check the alarm function and alarm action values.
Alarm function and alarm action value verification
The instrument's acoustic and light alarm should function normally. Insulation resistance.
Insulation resistance for instruments using AC power should not be less than 20MΩ.

The detection principle of the instruments mainly includes catalytic combustion, infrared absorption, and thermal conductivity types. The sampling methods include diffusion and aspiration. The instruments are primarily composed of detection elements, amplification circuits, alarm systems, and displays, used for monitoring the concentration of combustible gases in the environment.

Method of Verification
Appearance and structure
Inspect visually and by touch according to the requirements of 4.1
Logos and Branding
Inspect in accordance with the requirements of 4.2 by sight.
Power-on inspection
Inspect visually and by touch in accordance with requirements 4.3 to check the alarm function and alarm action values as per 5.3.4.
Introduce a standard gas substance with a concentration greater than the alarm setting point, causing the instrument to trigger an alarm. Observe whether the instrument's audio-visual alarm is functioning normally and record the instrument's reading when it alarms. Repeat the measurement three times; the arithmetic mean of the three readings is the instrument's alarm action value.

What factors can affect the calibration cycle of a combustible gas detector alarm?
Manufacturer Requirements: Different manufacturers may have varying inspection cycle requirements for their flammable gas detectors. Therefore, when purchasing equipment, carefully review the product manual to understand the specific requirements of the manufacturer.
Equipment Operating Environment: The operating environment of the alarm can directly affect its inspection cycle. If the equipment is exposed to a high concentration of harmful gases, high or low humidity, or high or low temperatures for an extended period, its inspection cycle may be accordingly shortened.
‌Equipment Maintenance Status: The condition of equipment maintenance is also a significant factor affecting the inspection cycle. If the equipment faces issues like battery depletion and sensor aging over a long period, the inspection cycle will accordingly be shortened.
Shenzhen Zhongnuo Testing Technology Co., Ltd. is a third-party service provider specializing in electrical safety, electrical explosion-proofing, gas alarms, and toxic and harmful gas detection instruments for regular inspections, metrological measurements, and calibrations. We are qualified to address fire and explosion prevention issues for our clients.