IEC 61753-131-03:2021 contains the minimum tests, test severities and measurement requirements which a mechanical fibre splice need to satisfy in order to be categorised as meeting the requirements of single-mode fibre splice for use in category OP (Outdoor protected) environments, as defined in IEC 61753-1. This document for mechanical splices defines the requirements for standard optical performance under a set of specified conditions. The standard contains a series or a set of tests and measurements with clearly stated conditions, severities and pass/fail criteria. The series of tests, commonly referred to as an operating service environment or performance category, is intended to be a basis to prove the product's ability to satisfy the requirements of a specific application, market sector or user group. This first edition cancels and replaces IEC 61753-131-3 first edition published in 2010. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a) addition of definitions;
b) addition of IEC 60068-2-10 mould growth test and test severities for materials;
c) replacement of the IEC 61753 1:2007 category U tests and test severities by the IEC 61753‑1:2018 category OP tests;
d) addition of the requirement that dimensions are in accordance with IEC 61756-1;
e) addition of the bending moment test;
f) change of low temperature in cold test and change of temperature test to −25°C. If 40°C is required, the user can refer to category OP+.