Shenzhen Zhongnuo Testing Technology Co., Ltd. specializes in the calibration, certification, and measurement services for gas alarms, combustible gas detectors, toxic and harmful gas detectors, and other equipment in various locations. We offer nationwide services to address electrical safety and explosion-proof fire prevention issues for clients, promoting safe production.
Method of Verification
Appearance and structure
Inspect and feel according to the requirements of 4.1
Branding and Identification
Inspect in accordance with the requirements of 4.2 by visual means.
Power-on inspection
Inspect visually and by touch, in accordance with 4.3 requirements, to check the 5.3.4 alarm function and alarm action values.
Introduce a standard gas substance with a concentration greater than the alarm set point, causing the instrument to trigger an alarm. Observe whether the instrument's audio-visual alarm is functioning properly and record the instrument's reading when the alarm is triggered. Repeat the measurement three times; the arithmetic mean of the three readings is the instrument's alarm activation value.

Gas Standard Material
We use gas standard substances of the same type as the measured gas by the instrument, such as methane or ethane, and other gases. If the instrument does not indicate the type of measured gas, the concentration of the gas set points (e.g., 60% of the full scale) should be approximated by a standard substance. The uncertainty of the expanded gas standard substances is not significant (%). The flow value error of the repetitive dilution device should not be greater than 1% for gas standard substances with a concentration not exceeding 0.%. The concentration unit of the dilution device for gas standard substances should be converted to match the units of the inspected instrument, and the deviation should not exceed 0.%.

What information is included in the calibration report for a flammable gas detector?
The verification results should be reflected in the verification certificate or report. 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 Certificate or report (e.g., numbered), with page numbers indicated on each page
Please provide the company name and address for shipping.
⑥ Describe and clearly identify the target school.
Calibration Date and Receipt Date
⑧ Technical specifications for calibration foundation, including names and codes;
Description of the traceability and validity of the measurement standards used for calibration.
⑩ Description of Calibration Environment
11. Calibration Results and Measurement Uncertainty Statement
12. Signature of the certifier or issuer of the calibration certificate or report, title or equivalent mark, and the date of issuance;
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 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, as well as after repairs, a recalibration is required.

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