New Changes Announced for Amendment No.3 BS7671 Wiring Regulations

Major Changes

Amendment no. 3 is a new yellow copy of the 17th edition coming out on the 1st January 2015, there is a 6 month implementation date, which means during this time period you can install to amendment 2 or amendment 3. As of 1st July, all electrical installations designed to the new amendment must be installed to the new amendment and certified to the new amendment. There is one major change, which is the numbering system. If the regulation is a European CENELEC, it’s now numbered 200, and if it’s a UK only regulation it’s now numbered 201.

Definition and Minor Changes

In definitions, some of the old definitions have been changed, such as a competent person, ordinary person and skilled person, which are all being changed. If you were defined as a competent person, this is no longer the case as it’s been completely removed from the regulations and is now classed as a ‘skilled person electrically’. In addition, every Zs value throughout BS7671 will be changing and this is because of a new factor coming in called Cmin. It’s going to reduce all existing Zs values by 0.05%. Cmin is the minimum voltage factor to take notice of variations in voltage, which depends on time and place and the changing of transformer taps.

Fire Safety Changes

Escape route installation methods have changed. You are no longer allowed to rely upon plastic or non metallic means of support, which means plastic trunking and plastic trays. You can still use it, but you have to fix it with metal fixings and make sure it doesn’t come down. Also, if you have used plastic ty-raps in the past, you now have to use metal ty-raps to stop cables dropping down in the event of a fire. Sticking to the theme of fires, consumer units will also have to change. Consumer units in domestic premises must be made of non combustible material. An example would be ferrous metal, such as steel. This particular regulation does not come into place until 1st January 2016.

Part 7 Changes

Within part 7 of BS7671, two new sections are being introduced, external light installations is one and extra low voltage lighting installation is the other. These have been brought from the main body of the regulations in their own sections within part 7. On electrical installation certificates, the schedule of items inspected used to be a tick box with 44 boxes, now its going to be 3 pages worth with 120 boxes.

These are the most significant changes that we have decided to let you know about, any other change will be very minor and in most cases unnoticeable. If any more news is given to use regarding amendment 3 we will be sure to let you know.

Take a further look at all the major changes made to BS7671 Amendment 3!

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