IEC 61300-2-18:2023 is available as IEC 61300-2-18:2023 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.

IEC 61300-2-18:2023 details a procedure to determine the suitability of a fibre optic interconnecting device, passive component, splices or closure to withstand the environmental condition of extended high temperature that occur during operation, storage and/or transport. The test is intended to indicate the performance of such devices when exposed to heat of constant temperature over a given period. In general terms, this test provides a high temperature to induce potential failures due to softening and expansions. This procedure does not assess the ability of a device to operate during temperature variations; in this case, IEC 61300-2-22 is used. This third edition cancels and replaces the second edition published in 2005. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
- terms and definitions updated according to IEC 61753-1:2018;
- test severities updated according to IEC 61753-1:2018;
- simplification of the combination of temperature and exposure time.