Shenzhen Zhongnuo Testing Technology Co., Ltd. specializes in the calibration, certification, and measurement services for equipment such as gas alarms, combustible gas detectors, and toxic gas analyzers for various locations. We provide services nationwide, addressing electrical safety and explosion-proof fire prevention issues for clients, and supporting safe production.
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 alternative substances like isopropanol can be used. If the instrument does not specify the type of gas being measured, the concentration of the gas at the set point, such as methane, ethane, or other gases, is approximately 60% of the full scale. The uncertainty of the expanded gas standard substance is not more than % (the uncertainty of the standard gas substance is greater than ±1%). The flow indication error of the repeatability dilution device should not be higher than the concentration of the gas standard substance. The concentration unit of the dilution device for the gas standard substance should be converted to match the unit of the instrument being tested, and the discrepancy should not exceed 0.%.

What factors affect the calibration cycle of flammable gas detectors?
Manufacturer Requirement: Different manufacturers' flammable gas detectors may have varying inspection cycle requirements. 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 directly affects its inspection cycle. If the equipment is frequently exposed to high concentrations of harmful gases, high humidity, or extreme temperatures (either high or low), the inspection cycle may be shortened accordingly.
‌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 or sensor aging over a long period, the inspection cycle will accordingly be shortened.

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 clean, with a uniform paint and coating without any peeling or rusting.
The instrument's connections are reliable, and all dials or buttons should operate and control normally.
Logos and trademarks
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 domestic instruments should be clear.

What are the contents included in the calibration report for flammable gas detectors?
The verification results should be reflected in the verification certificate or report, and the verification proof or report must include the following information.
Calibration Certificate or Calibration Report
② Laboratory Name and Address
③ Calibration Location (if not calibrated in the laboratory)
④ Standing proof or report (e.g., with serial number), indicating each page and its number;
⑤Shipper's name and address
⑥ Describe and clearly identify the school target.
Calibration Date and Receipt Date
⑧ Technical specifications for calibration basis, including names and codes;
⑨ Description of traceability and effectiveness of the measurement standards used for calibration.
⑩ Description of Calibration Environment
11. Calibration Results and Measurement Uncertainty Statement
12. Signature, title or equivalent symbol, and issuance date of the certifier or issuer of the calibration certificate or calibration report
13. Calibration results are only applicable to the calibration object.
14. No part of the certificate or report may be copied without written consent from the laboratory.
Re-review interval
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 required after repairs.
Shenzhen Zhongnuo Testing Technology Co., Ltd. is a third-party institution specializing in electrical safety, electrical explosion-proofing, gas alarm systems, and toxic/hazardous gas alarm instruments for regular inspections, metrological measurements, and calibrations. We are licensed to help clients address fire and explosion prevention issues.