Shenzhen ZhongNuo Testing Technology Co., Ltd. specializes in the calibration, verification, and metrological services for gas alarms, combustible gas detectors, and toxic gas detection instruments at various locations. We hold the necessary qualifications to serve nationwide, addressing clients' electrical safety and explosion-proof fire prevention issues, and contributing to safe production.
Gas Alarm Meters Calibration Conditions and Requirements
Environmental Conditions
Ambient Temperature: 0~40℃.
2. Relative Humidity: ≤85%
3. The working environment should not interfere with the normal operation of the instrument through electromagnetic fields and disturbing gases.
Inspection Gauges and Instruments
1) Certified Reference Materials for Gases
The relative expanded uncertainty of the gas standard material does not exceed 2% (k=2).
2) Standard Gas Dilution Unit: Dilution error of 1%.
3) Stopwatch: Graduation not greater than 0.1s.
4) Flow Control: Flow range not less than 500 mL/min, flow grade not less than level 4.
5) Zero Point Gas: Purified compressed air.
6) Pressure Reducing Valve: A pressure reducing valve that matches with the calibrated cylinder.
7) Gas Pipeline: Tube made of materials like polytetrafluoroethylene or stainless steel that do not affect the concentration of the measured gas.

Regulatory Content and Methods for Regular Detection of Flammable Gas Detectors
Annual inspections of industrial and commercial alarm sensors are conducted regularly, primarily to check for the accuracy, repeatability, drift, and response time of the alarms against standards. Additionally, the suitability of the alarm installation location and any interference from other equipment are assessed.

The principle of instrument detection mainly includes catalytic combustion, infrared absorption, and thermal conductivity types. 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.

What does a calibration report for a combustible gas detector include?
The verification results should be reflected in the verification certificate or report, and the verification proof or report must include the following information.
① Calibration Certificate or Calibration Report
② Laboratory Name and Address
③ Calibration Location (if not calibrated in the laboratory)
④ Certificate or report (e.g., numbered), with page numbers and total page count indicated on each page
Please provide the name and address of the shipping entity.
⑥ Describe and clearly identify the target school.
Calibration date and receipt date;
⑧ Technical specifications for calibration base, including names and codes;
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 of the issuer of the calibration certificate or report, and the issuance date;
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-proofreading interval
Instrument recalibration is typically every 1 year, determined by the sending unit based on actual usage. During the re-calibration process, if there are questions about the instrument's test data, or if the main components of the instrument are replaced, as well as after repairs, recalibration is required.
Shenzhen ZhongNuo Testing Technology Co., Ltd. is a third-party institution that specializes in electrical safety, electrical explosion-proofing, gas alarm systems, and toxic/hazardous gas alarm instruments for regular inspections, metrological services, and calibration. We are licensed to assist clients in addressing fire and explosion prevention issues.