What is the difference between an ESC, COC, ROI and CoV?

An ESC (Electrical Safety Certificate) and COC (Certificate of Compliance) are issued by the electrician who carried out the work. An ROI (Record of Inspection) is issued by a registered inspector after inspecting high-risk work such as mains work. A CoV (Certificate of Verification) confirms an existing installation is electrically safe, and is what insurers, banks and councils usually mean by an energy works certificate. Our certification guide explains each in plain English.