This part of IEC 60794-1 defines test procedures to be used in establishing uniform requirements for the environmental performance of " optical fibre cables for use with telecommunication equipment and devices employing similar techniques, and " cables having a combination of both optical fibres and electrical conductors. Throughout this document, the wording "optical cable" can also include optical fibre units, microduct fibre units, etc. This document defines a test standard to determine cable aging performance by high temperature exposure and temperature cycling in order to simulate life-time behaviour of the attenuation of cables, or physical attributes. See IEC 60794-1-2 for a reference guide to test methods of all types and for general requirements and definitions.