1 Scope

This document provides guidance on the interpretation of backscattering traces, as obtained by traditional optical time domain reflectometers (OTDRs) for single-mode fibres.

This document does not cover Polarization OTDRs.

Also, backscattered power effects are discussed in case of unidirectional trace.

Full description of the test measurement procedure can be found in Annex C of IEC 60793‑1‑40:2024 [1].