IET Guidance Note 2: Isolation & Switching, 10th Edition

The IET Guidance Note 2 provides focused guidance on isolation and switching requirements within electrical installations. It is intended for professionals involved in design, inspection, testing, maintenance, and operational control.

Updated to align with BS 7671 (18th Edition Amendment 4:2026), this edition clarifies the correct application of isolation and switching principles in practical scenarios. It covers the isolation of multipole source systems and guides on selecting appropriate protective, isolation, and switching devices.

The content also addresses bidirectional and unidirectional devices, along with requirements for firefighters’ switches. This guidance note is designed to reduce ambiguity in interpreting the regulations, supporting safe and compliant system design and operation.

Expected by: 01 June 2026