Shenzhen ZhongNuo Testing Technology Co., Ltd. specializes in the calibration, certification, and metrological services for equipment such as gas alarms, combustible gas detectors, and toxic gas analyzers for various locations. We offer services nationwide, addressing electrical safety and explosion-proof fire prevention issues for our clients, and contributing to safe production.
How often is it required to regularly calibrate and check the various gas detectors?
The recalibration time for instruments is typically 1 year, which is determined by the sending unit based on actual usage. During the re-calibration process, if there are any doubts about the instrument test data, or if the main components of the instrument are replaced, or if the instrument needs to be recalibrated after repair.

Gas Standard Material
We use gas standard substances of the same type as the gas measured by the instrument, such as methane or ethane, or gas standards can be expanded with isopropanol, etc. If the instrument does not specify the type of gas being measured, the concentration of the gas with a 60% span set point is approximately the full-scale standard substance. The uncertainty of the expanded gas standard substance is not significant (%), and the standard substance with a repeatability of more than 1% should not have a flow indication error greater than 0.%. The concentration unit of the gas standard substance should be converted to match the measuring unit of the inspected instrument when in use, and should not exceed 0.%.

Regular Inspection Items for Workplace Environmental Gas Detection and Alarm Equipment
Alarm sound and light (if applicable)
2. Small response value
3. Indicating Error (for Gas Detectors/Gas Detector Alarms)
4. Instrument Drift (in Portable Instruments)
5. Alarm Error (for Gas Detection Alarm / Gas Alarm)
6. Pump Suction Instrument Gas Sampling Distance and Flow Rate (for Pump Suction Instruments)
7. Power Supply (for battery-powered instruments)
8. Response Time
9. Status Indicator (with Wireless Communication Function)

Standard for inspection and metrological calibration of flammable and toxic gas detectors:
GB/T 50493-2019 "Design Standard for Detection and Alarm of Combustible and Toxic Gases in Petroleum and Chemical Industries"
GB12358-2006 General Technical Requirements for Environmental Gas Detection and Alarm Instruments in Workplace
JJG 693-2011 "Regulation for Calibration of Combustible Gas Detectors"
Shenzhen ZhongNuo Testing Technology Co., Ltd. is an independent third-party institution providing regular calibration, metrological testing, and calibration services for electrical safety, electrical explosion-proofing, gas detectors, and toxic and harmful gas alarm instruments. We are qualified to help customers address fire and explosion prevention issues.