IEC 61280-4-2:2024 is available as IEC 61280-4-2:2024 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.

IEC 62180-4-2:2024 is applicable to the measurements of attenuation and optical return loss of an installed optical fibre cabling plant using single-mode fibre. This cabling plant can include single-mode optical fibres, connectors, adapters, splices, and other passive devices. The cabling can be installed in a variety of environments including residential, commercial, industrial and data centre premises, as well as outside plant environments. This document is applicable to all single-mode fibre types including those designated by IEC 60793-2-50 as Class B fibres. The principles of this document can be applied to cabling plants containing branching devices (splitters) and at specific wavelength ranges in situations where passive wavelength selective components are deployed, such as WDM, CWDM and DWDM devices. This document is not intended to apply to cabling plants that include active devices such as fibre amplifiers or dynamic channel equalizers. This third edition cancels and replaces the second edition published in 2014. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a) addition of the equipment cord method;
b) addition of test limit adjustment related to test cord grades;
c) refinements on measurement uncertainties.