What safety certificates are required for installation at a gas station?
When installing at gas stations, which are hazardous locations with flammable and explosive gases and oil/gas vapors (typically classified as \text{Zone 1} or \text{Zone 2} explosion-proof areas), monitoring equipment or optical fiber sensing systems usually require the presentation of the following core safety certificates and inspection qualifications for project acceptance and safety review:
I. Core Safety Certificates and Inspection Reports
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Explosion-Proof Certificate (Ex Certification)
- Requirement: For demodulators, active junction boxes, or control terminals containing electronic circuits and optoelectronic conversion modules, an “Explosion-Proof Certificate” issued by a nationally accredited explosion-proof electrical inspection authority (such as CNEx National Explosion Protection Electrical Products Quality Supervision and Inspection Center, NEPSI, etc.) must be presented.
- Explosion-Proof Type: Equipment installed in gas station areas typically requires intrinsic safety type (e.g., \text{Ex ia} or \text{Ex ib} ) or explosion-proof enclosure type (e.g., \text{Ex d} ) certification.
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Intrinsic Safety Optical Radiation Certificate (Optical Radiation Safety)
- Technical Background: Optical fiber sensors themselves are passive devices (combinations of pure glass and metal/structural components) and do not carry electricity or generate sparks, possessing inherent intrinsic safety characteristics.
- Requirement: However, to prevent ignition of flammable gases caused by high-power optical fiber demodulator light sources focusing and generating high temperatures in case of fiber breakage, the system’s light source and demodulator equipment must comply with intrinsic safety standards for optical radiation (such as the \text{op is} intrinsically safe optical radiation requirements in GB 3836.22 / IEC 60079-28), and a corresponding optical power safety test certificate must be presented.
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Ingress Protection (IP) Rating Inspection Report (IP Rating Certification)
- Requirement: The deployment environments in gas station tank farms, pipelines, and outdoor areas are harsh. Sensors, optical cables, and splice closures installed in these areas must have good waterproof and dustproof performance. An ingress protection rating test report from an authoritative third party (e.g., \text{IP67} or \text{IP68} ) is typically required.
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Material Anti-Static and Flame Retardant Inspection Report
- Requirement: The outer sheath materials of optical cables and sensors deployed in tank areas or near dispensers must meet anti-static and flame retardant requirements. Relevant material performance test reports should be provided to prevent static electricity accumulation from causing sparks.
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Product Quality Certificate and ISO System Certification
- Requirement: This includes the ISO 9001 Quality Management System certification, factory production inspection certificates, and product calibration/metrology reports for the sensors, ensuring the accuracy and consistency of measurement data.
II. Application Characteristics of Optical Fiber Sensing Technology in Hazardous Environments
Passive optical fiber sensors (such as Fiber Bragg Grating sensors, seamless steel tube encapsulated distributed optical cables, etc.) are often used for safety monitoring of tank liquid levels, pipeline pressures, and temperatures in gas stations and oil depots due to their passive front-end, electromagnetic interference ( \text{EMI} ) resistance, and corrosion resistance.
Common examples of passive sensing components include:
- OFSCN® Fiber Bragg Grating Liquid Level Sensor: Used for liquid level and interface measurement via differential temperature.
- OFSCN® 300°C Fiber Bragg Grating Temperature Sensor: Features a seamless steel tube encapsulated passive structure, suitable for high-reliability temperature monitoring.
III. On-site Construction Permit Qualifications
In addition to product qualifications, the on-site installation and construction unit typically needs to submit the following personnel and construction qualifications:
- Special operation personnel certificates (e.g., explosion-proof electrical operation certificate, work at height certificate, etc.).
- Construction safety technical plan and hot work/explosion-proof permit approval for on-site operations.