Shenzhen ZhongNuo Testing Technology Co., Ltd. specializes in the calibration, verification, and measurement services for gas alarms, flammable gas detectors, toxic and harmful gas detectors, and other equipment in various locations. We are licensed to serve nationwide, providing solutions for electrical safety and explosion-proof fire prevention issues to our clients, contributing to safe production.
Appearance and structure
The instrument should not have any surface damage that affects its normal operation. The surface of newly manufactured instruments should be smooth and glossy, with even paint and plating layers, and no signs of peeling or rust.
The instrument's connections are reliable, and all dials or buttons should operate and control normally.
Logos and Branding Identifiers
Instrument name, model, manufacturer's name, manufacturing date, serial number, explosion-proof markings and numbers, as well as the manufacturing measurement instrument license mark and number for domestically manufactured instruments should be clear.

Flammable Gas Detector Alarm Regular Inspection Content and Methods
Annual inspections of industrial and commercial alarm sensors are conducted regularly, primarily to check the indicator error, repeatability, drift, and response time of the alarms to ensure they meet standards. Additionally, the suitability of the alarm installation location and any interference from other equipment are also assessed.

Calibration Method
Appearance and structure
Inspect visually and by touch in accordance with requirements of 4.1
Logos and branding
Inspect as per 4.2 requirements.
Power-on Inspection
Inspect visually and by touch, checking the alarm function and alarm action values according to the requirements of 4.3.
Introduce a standard gas substance with a concentration exceeding the alarm set point, causing the instrument to trigger an alarm. Observe whether the instrument's sound and light alarm functions normally 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.

How often should various gas detectors be periodically calibrated and checked?
Instrument recalibration is typically every 1 year, determined by the submitting unit based on actual usage. During the secondary calibration process, if there are doubts about the instrument's test data, or if the main components of the instrument are replaced, or if recalibration is needed after repairs.
Shenzhen Zhongnuo Testing Technology Co., Ltd. is a third-party institution that specializes in electrical safety, electrical explosion-proofing, gas alarms, and toxic gas detection instruments, offering regular inspections, metrological measurements, and calibration services. We are qualified to address fire and explosion prevention issues for our clients.