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Fibre Connector Inspection – IEC 61300-3-35
Fibre Connector Inspection and IEC 61300-3-35
IEC 61300-3-35 provides procedures and criteria for visually inspecting fibre optic connector and fibre-stub transceiver end faces for contamination, scratches and defects.
Scope
Visual inspection equipment, procedures and quantitative criteria used to evaluate fibre optic end-face cleanliness and defects.
Who this guidance is for
Fibre installers, testing engineers, maintainers, manufacturers, training providers and quality assurance personnel.
Installation relevance
Inspection and cleaning should form part of the connection process. Visual inspection supports cleanliness control but does not replace optical performance measurements.
Qualifications and competence
Fibre qualifications should include safe inspection, appropriate cleaning, pass/fail assessment and the relationship between visual and optical performance.
Key points
Inspect before connection.
Use suitable inspection equipment.
Assess the relevant end-face zones.
Clean using an appropriate process when necessary.
Reinspect after cleaning.
Do not treat inspection as a substitute for attenuation or return-loss measurement.
Authorised publication
International Electrotechnical Commission · IEC 61300-3-35:2022
View the publisher’s standard information
Standards overview · Knowledge Hub
Reviewed by Paul Forster, COFNII Chairman
Last reviewed: 10 September 2026