Terms, supplies and bonding
Part 2 · Regulation 312.2.1.1
The change map identifies expanded or modified definitions and a protective neutral bonding (PNB) figure with associated requirements.
CURRICULUM UPDATE · TOPIC AWARENESS
BS 7671:2018
+A4:2026
An original topic index based on the owner-supplied A4 change map. Use it to find the right area in the current source, then verify the actual requirement there.
Technical review requiredThis page is based on the owner-supplied change map. It does not state exact regulatory requirements and is not guidance for designing, installing, inspecting, testing or certifying electrical work.
What to revisit
Use this as an index, not as the rule.
These original summaries identify subject areas only. Check the current BS 7671:2018+A4:2026 text and relevant official guidance for the actual requirements, and seek competent technical review before applying them.
Thermal protection and escape routes
Regulations 421.1.7(a) · 422.2
The map flags a change concerning high-rise residential buildings and a substantial revision relating to protected escape routes, including cable arrangements in relevant corridors and fire-resisting enclosures.
Overcurrent and conductor connections
Regulations 434.2.1 · 434.3(a)
The change map identifies revised conductor-connection provisions, including Regulation 434.3(a), and permitted inherently short-circuit and earth-fault-proof arrangements.
Identification and wiring systems
Table 51 · Regulations 521.10.202 · 522.6.202 · Table 52.1
A4 revises conductor identification and support requirements. For cables in walls and partitions, the relevant arrangement is addressed under Regulation 522.6.202 and Table 52.1.
Switchgear coordination and isolation
Regulations 536.4.202 · 537.4.2
The map highlights revised coordination between assemblies and protective devices, plus isolation and switching topics, including firefighter switching in applicable locations.
Functional earthing and bonding
New Section 545
The new section covers functional earthing and functional equipotential bonding for information and communication technology equipment and systems, including combined protective and functional arrangements.
Generating sets and safety services
Regulations 551.7.1 · 551.7.2 · 560.5.3 · 560.6
The change map identifies revisions for low-voltage generating sets, residual current protection in specified circumstances, assemblies in stated connection arrangements, and electrical sources for safety services.
Stationary secondary batteries
New Chapter 57
Chapter 57 addresses stationary secondary batteries used for storage and supply in electrical installations. It excludes batteries incorporated into product-standard equipment and specified UPS, fire/emergency lighting and central safety-power systems. Check the full current standard for exact scope.
Periodic inspection and reporting
Regulations 653.1 · 653.2 · Appendix 6
The map points to Condition Report notes, report-recipient guidance and the Appendix 6 model. It identifies subjects to locate in the current source, not inspection instructions.
Medical locations and power over Ethernet
Sections 710 · 716
Section 710 is identified as substantially revised, including Group 2 medical IT systems and supplementary protective equipotential bonding. New Section 716 addresses distribution of ELV DC power over suitable balanced IT cabling and verification topics.
Energy efficiency and reference material
Chapter 81 · Appendices 1 and 4 · Annex B443
A4 adds Chapter 81 on energy efficiency. It deletes Annex B443 and Appendix 17; the energy-efficiency topic previously covered in Appendix 17 is now in Chapter 81.
An official A4 example
Inspection reports: understand the updated context.
The IET’s July 2026 article explains changes relating to the Further Investigation classification in EICR reporting. Read the source and current standard together; this summary does not determine a report outcome or replace a competent person’s judgement.
Read the IET articleWorking from the current source
Check the Orange Book before applying a change.
BS 7671:2018+A4:2026 was issued on 15 April 2026. The supplied final-edition introduction gives 15 October 2026 as the withdrawal date for the previous A2+A3 edition. The full current standard remains the authority for exact requirements.
Independent supplementary learning. This page is not an official IET or City & Guilds publication, does not reproduce BS 7671 wording, and is not a substitute for training, supervision or competence.