Guidance Note 1: Selection & Erection is a fundamental guide for specifiers, installers and those inspecting and testing installations. It contains clear guidance on how to apply the relevant sections of BS 7671 and has been fully updated to BS 7671:2018. The 18th Edition of the IET Wiring Regulations published in July 2018 and came into effect in January 2019. Changes from the previous edition include requirements concerning Surge Protection Devices, Arc Fault Detection Devices and the installation of electric vehicle charging equipment as well as many other areas.