Shenzhen ZhongNuo Testing Technology Co., Ltd. specializes in calibration, certification, and measurement services for gas alarms, flammable gas detectors, and toxic gas monitors in various locations. We serve nationwide, providing solutions for electrical safety and explosion-proof fire prevention issues, contributing to safe production.
Power-on inspection
The instrument should operate normally after being powered on, with the display sections clear and complete. Check the alarm function and the alarm action values.
Alarm function and alarm action value check
The instrument's acoustic and visual alarm should be functioning normally. Insulation resistance
Insulation resistance for instruments using alternating current power should not be less than 20MΩ.

GB 12358-2024 "General Technical Requirements for Environmental Gas Detection and Alarm Instruments in Workplace" is an important standard.
Intended to standardize the performance, functions, and testing methods of environmental gas detection and alarm instruments used in work sites.
The standard was published in 1990 and has undergone multiple revisions.
The new version is GB 12358—2024, which will be officially implemented on June 1, 2025.
This standard applies to the production and use of gas detection and alarm instruments for flammable gases, toxic and harmful gases, and oxygen in workplace environments.

Standard for calibration and verification of combustible and toxic gas detectors:
GB/T 50493-2019 "Design Standard for Detection and Alarm Systems of Combustible Gases and Toxic Gases in Petroleum and Chemical Industries"
GB12358-2006 General Technical Requirements for Environmental Gas Detection and Alarm Instruments in Workplaces
JJG693-2011 "Regulation for Calibration of Combustible Gas Detectors"

What are the contents included in the calibration report for flammable gas detectors?
The verification results should be reflected on 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 Standby letter of credit or report (e.g., numbered), with indication of page number and total pages
5. Shipper's name and address
⑥ Describe the target school clearly and explicitly.
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 Statements
12. Signature of the Issuer of Calibration Certificate or Calibration Report, Position or Equivalent Mark, and Date of Issue
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.
Two-time 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 alarms, and toxic and harmful gas detection instruments, offering regular inspections, metrological measurements, and calibration services. We are qualified to address fire and explosion prevention issues for our clients.