IEC 61156-5-1:2009(E) describes symmetrical pair/quad cables intended primarily for horizontal floor cabling as defined in ISO/IEC 11801 and ISO/IEC 24702. It includes additional recommended environmental characteristics and severities which are derived from the environmental classifications that are specified for cabling for various environments. This edition constitutes a technical revision and includes the following significant technical changes with respect to the previous edition:
- new requirements for new cables Cat6A and Cat7A;
- revised requirements and tests for the cables.

This publication is to be read in conjunction with IEC 61156-1:2007 and IEC 61156-5:2009.