IET Guidance Note 3 Inspection & Testing, 10th Edition (BS 7671:2018+A4:2026)

Guidance Note 3 is a key reference for anyone involved in the inspection and testing of electrical installations. Fully updated to align with BS 7671:2018+A4:2026, it offers clear explanations of the requirements and practical detail to support accurate testing, verification and documentation.

Widely used by practising electricians and those preparing for inspection and testing qualifications, this guide remains one of the most important resources for understanding safe and compliant testing procedures. An official erratum is available and should be inserted into originally printed versions to ensure accuracy.