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Month: April 2022

18th Edition changes for 2022

The 18th Edition is an important resource for all professional electricians and is the more common name for the IET (Institute of Engineering and Technology) wiring regulations.

It is an essential source of reference and information designed to ensure that all electrical installations are safe and functioning properly.

Setting out the British standard for the installation of electrical wiring (BS 7671), the 18th Edition details the guidelines and processes that must be followed to adhere to the Electricity at Work regulations.

It covers new installations as well as additions, alterations and maintenance of existing ones. It ensures they all meet the current standard for safety and efficiency.

The 18th Edition was first published in 2018 and has since gone through various updates and amendments that reflect the development and ever-changing requirements and best practice in the industry.

Key changes to the 18th Edition

The latest amendments to the 18th Edition came into effect in March this year.

Here’s a summary of the key changes:

Arc Fault Detection Devices (AFDDs)

A new regulation 421.1.7 has been added. It recommends the installation of AFDDs in residential buildings that are susceptible to arc faults, to reduce the risk of fire.

Protection against electric shock

Section 411 contains various key changes, including a new regulation (411.3.4) applying to domestic premises that requires additional protection to be provided by an RCD for AC final circuits supplying luminaires.

Installation of wiring systems

Regulation 521.10.202 has changed the requirement for cables in escape routes to be properly supported. It now specifies that cables in all areas of the installation be supported to prevent collapse during a fire.

Electric vehicle (EV) charging

Changes to Section 722 (regulation 722.411.4.1) cover the use of a PME supply.

Energy efficiency

A new appendix has been added concerning energy efficiency in the design and installation of electrical wiring.

Fire safety

Amendment 2 details that any ‘protected escape routes’ (defined as escape routes from a building that have been specifically planned to withstand fire) must be properly documented.

Overvoltage protection

Amendment 2 also clarifies the implementation of Surge Protection Devices (SPDs) and when they should be used to protect against overvoltage. It provides a guide to which circumstances of an overvoltage would warrant the installation of SPDs. These are:

• Serious injury or loss of human life

• Failure of safety equipment or system

• Significant financial or data loss

Safety information

With reference to SPDs above, Amendment 2 also contains an addition specifying that, where SPDs are installed, clear and up-to-date safety information must be displayed.

Alternative means of power

Part 8 is a new section within the 18th Edition that reflects the move towards alternative power sources, not least because of the UK Government’s ambition to reach net zero emissions by 2050.

The installation of alternative means of generating power, such as solar panels and wind turbines, are covered by this new section of the regulations.


All of DRF Electrical’s installations are carried out and tested in accordance with the latest British Standards BS7671 and the 18th Edition IET wiring regulations.