Wenzhou Gas Detector Calibration - Zhongnuo Inspection

Shenzhen ZhongNuo Testing Technology Co., Ltd. specializes in the calibration, certification, and measurement services for gas alarms, flammable gas detectors, toxic and harmful gas detectors, and other equipment in various locations. We offer services nationwide, addressing clients' electrical safety and explosion-proof fire prevention needs, and contributing to safe production.
Measurement Instrument Control
The instrument control includes calibration, follow-up calibration, and in-service inspection.

Verification Method
Appearance and structure
Inspect visually and by touch according to the requirements of 4.1
Logos and branding
Inspection to be conducted according to the requirements of 4.2.
Power-on inspection
Inspect visually and by touch in accordance with requirements 4.3 to check the alarm function and alarm action values as per 5.3.4.
Introduce a standard substance with a gas concentration exceeding the alarm set point, causing the instrument to trigger an alarm. Observe if the instrument's audible and visual alarms function properly and record the instrument's reading at the time of alarm. Repeat the measurement three times; the arithmetic mean of the three readings is the instrument's alarm action value.

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. 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 Standing proof or report (e.g., with serial number), indicating each page and the total number of pages;
⑤Shipper's name and address
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, title or equivalent symbol, and date of issuance by the certifier or report 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.
Two proofreading intervals
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 needed after repairs.

Key Technical Requirements for Regular Calibration of Combustible Gas Detectors (Shenzhen ZhongNuo Inspection Technology Co., Ltd.)
1. Power-On Self-Check Function: The instrument should have an automatic self-check function upon startup, and a manual self-check function should be set for alarm components.
2. Specify the effective detection range: The effective detection range of the non-contact gas alarm instrument shall not be less than 20 meters.
3. Alarm Value Setting: The standard specifies specific alarm value settings for different gases.
For example, the oxygen deficiency alarm setting is 19.5%VOL, and the oxygen-rich alarm setting is 23.5%VOL (refer to GB 8958-2006 "Operation Procedures for Oxygen Deficiency Hazardous Operations" and GB 30871-2022 "Special Operation Regulations for Hazardous Chemical Enterprises").
The first-level combustible gas alarm setting is not greater than 25% LEL, and the second-level alarm setting is not greater than 50% LEL.
The first and second level alarm settings for toxic and harmful gases are determined based on OEL (Occupational Exposure Limit) or IDLH (Immediate Danger to Life and Health).
4. Error and Repetition: The standard specifies clear requirements for the instrument's indication error, drift, and repeatability. For instance, the indication error for combustible gases, toxic and harmful gases, and oxygen should not exceed 5% FS, 5% FS, and 2% FS respectively within the normal test range of the instrument's full scale.
5. Calibration and Interface: The instrument should be easy to calibrate, and calibration programs and corresponding interfaces should be set up to ensure the accuracy of its measurement results.
6. Explosion-proof Performance: Equipment used in explosive environments must possess explosion-proof properties in accordance with relevant regulations and obtain an explosion-proof certificate.
7. Audio-Visual Alarm Devices: The audio-visual alarm devices of the alarm should meet visibility and sound pressure level requirements under specific conditions to ensure effective alerting of staff in emergency situations.
8. Output Control Function: Instruments with output control capabilities should be able to activate the output control function upon emitting an alarm signal, such as cutting off power or initiating the exhaust system, etc.
9. Power Requirements: Specific requirements are set for the supply voltage, continuous operating time, etc., for battery-powered and non-battery-powered instruments.
10. Additional Performance Requirements: Includes specifications for bearing, response time, full-scale indication error, high-speed airflow, long-term stability, insulation withstand voltage, temperature, constant humidity and heat, electromagnetic interference resistance, steam interference resistance, vibration and drop, and functionality.
Shenzhen Zhongnuo Testing Technology Co., Ltd. is a third-party institution that provides regular calibration, measurement, and certification services for electrical safety, electrical explosion-proof equipment, gas detectors, and toxic and harmful gas alarm instruments, as well as资质 solutions to address fire and explosion prevention issues for clients.