Shenzhen Zhongnuo Testing Technology Co., Ltd. specializes in the calibration, verification, and measurement services for gas alarms, combustible gas detectors, toxic and harmful gas detectors, and other equipment in various locations. We hold the necessary qualifications to serve nationwide, providing solutions for electrical safety and explosion-proof fire prevention issues, and contributing to safe production.
Regular inspection items for environmental gas detection and alarm instruments in workplace operations:
Alarm sound and light (if applicable)
2. Low 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-Actuated Instrument Gas Sampling Distance and Flow Rate (for Pump-Actuated Instruments)
7. Power Supply (for battery-powered instruments)
8. Response Time
9. Status Indicator (with Wireless Communication Function)

GB 12358-2024 "General Technical Requirements for Environmental Gas Detection and Alarm Instruments in Workplaces" is an important standard.
Intended to standardize the performance, functions, and testing methods of environmental gas detection and alarm instruments used in workspaces.
The standard was issued in 1990 and has undergone several 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 detection and alarm instruments for flammable gases, toxic and harmful gases, and oxygen in workplaces.

Gas Detector Alarms Calibration Standards Requirement
Regulation 5.5 of the "Regulation for Calibration of Combustible Gas Detectors" (JJG693-2011) states: The calibration period for combustible gas detection and alarm instruments: Generally, the calibration period for the instrument should not exceed one year. Instruments with suspected measurement data, instruments that have replaced major components, or instruments that have been repaired should be submitted for calibration promptly.
Section 3.5 of the "Regulations for the Use of Combustible Gas Detection and Alarm Systems" (SY6503-2000) stipulates: The combustible gas detection and alarm systems in use shall be calibrated regularly as per the regulations.
Occupational Health Services - Code for the Installation of Toxic Gas Devices (GBZ/T223-2009), Article 7.2.1 stipulates: Calibration of detection and alarm devices should be performed regularly according to the manufacturer's specified time and procedures.
Section 3.4 of the "Code for the Use of Combustible Gas Detectors and Alarms" (SY6503-2000) stipulates: Combustible gas detectors and alarms for installation and use shall have measurement instruments manufactured by an institution recognized for their **explosion-proof performance**.

Regulatory Contents and Methods for Routine Detection of Flammable Gas Detectors
Annually, we conduct annual inspections on the sensors of commercial and industrial alarms, primarily checking for the accuracy, repeatability, drift, and response time of the alarms to ensure they meet standards. Additionally, we verify the suitability of the alarm installation location and check for interference from other equipment.
Shenzhen Zhongnuo Testing Technology Co., Ltd. is a third-party institution specializing in electrical safety, electrical explosion-proofing, gas alarm systems, and toxic and harmful gas detection instruments, providing regular inspections, metrological measurements, and calibration services. We are qualified to help clients solve fire and explosion prevention issues.