18th Edition Wiring Regulations: What’s Changed?

The British Standard BS 7671 is an essential guide for those who work with commercial electrical environments in the UK. A new edition has recently been published in which it has reconsidered some specific aspects of installation, maintenance, and methods for dealing with cases related to electrical equipment.

The 18th wiring regulation was published on July 2, 2018, and is scheduled to take effect on January 1, 2019. It is important to note that buildings built before the effective date must meet the requirements of this new manual.

In today’s blog post we offer you a list of the most significant changes, although this does not exempt you from reading the entire document! We recommend that you purchase the book as soon as possible.

The 18th wiring regulation now explained

The first two parts of the regulation explain some basic definitions of materials, installation equipment and concepts of electrician exercise. Unlike previous ones, from the 18th edition onwards, all specialists must have a document issued by the Electrical Installation Certificate.

  • Chapter 41 (Protection against electric shock) contains important changes, such as socket-outlet 32A disconnect time and RCD usage conditions. New regulations on IT systems and electronic equipment with limited short-circuit current were also published in this new manual.
  • Chapter 42 (Protection against thermal effects) endorses the use of arc fault detection devices (AFDDs) to mitigate the possibility of fire in electrical circuits. It is also recommended that cables should meet the minimum requirements of the CPR for both normal and safety wiring.
  • A new chapter, number 46, has been added to this edition. It deals with the conditions of remote isolation and switching measures that electronic equipment must meet. These rules complement chapter 44 related to protection against voltage disturbances and electromagnetic disturbances which has been modified according to the real risks of over voltage according to the conditions of each electrical installation and chapter 53 (Protection, isolation, switching, control and monitoring).
  • If you want to install a protective conductor to electrical devices, it is necessary to read chapter 54, which has been extended to regulate operations on devices powered by more than one power source.
  • Part 6 of the manual describes the inspection and testing processes for electrical installations. It indicates that all of these must be endorsed by CENELEC.
  • The following sections refer to cases of electrical installations such as in camps, medical institutes, vehicles such as electric cars, caravans, and boats. It describes mandatory safety procedures, tools and equipment, proper installation conditions and any other events that influence electrical work.
  • Some appendices have been slightly modified after an exhaustive review process. As a feature, a new appendix has been added related to legal recommendations for energy saving and optimisation of its use.

The 18th wiring regulation is reading that you should not overlook. Remember to follow all these statutes for a safe, efficient and durable electrical installation.


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