Amendment No. 3 to BS 7671:2008 – What You Need to Know

On January 5th 2015, Amendment No. 3 to BS 7671:2008 – Requirements for Electrical Installations, will be published. The new regulations will come into effect on July 1st 2015 and all new installations from this date must comply with the changes. Between January and the end of June, electricians may install to amendment 2 or amendment 3.

The 17th edition of the Wiring Regulations will have a new reference: BS 7671:2008+A3:2015.

Proposed Changes to the Wiring Regulations

The Institution of Engineering and Technology (IET) has provided a preview of some of the proposed changes to the Wiring Regulations. The full details of all changes will not be available until the amended regulations are published in January but here’s what we know so far:

Changes to Earth Fault Loop Impedances

This is one of the most important proposed changes. Amendment 3 will see a reduction in all maximum earth loop impedance values for protective devices. The current values are based on a set supply voltage of 230V, but it is possible for the supply to dip below 230V.

For safety and accuracy reasons a new minimum voltage factor has been introduced. This will take into account possible voltage variations. In addition, the earth loop impedance tables have been updated to allow for the new voltage factor and lower supply voltages.

Changes to Definitions

Definitions of key terms and phrases throughout the Regulations will be modified and expanded for clarity. For example, the definition of ‘skilled and instructed persons’ will be updated, while the definition for ‘competent person’ will be removed. The definitions will include new symbols too.

Updated Electrical Installation Condition Report and Certification

The updated Regulations will include changes to the electrical installation condition report and related notes.

Certification forms will be significantly updated, as will the inspection schedules. The new schedules are designed to make carrying out inspections more organised and efficient. They provide a comprehensive breakdown of the inspection required on all aspects of a new installation with tick boxes for each area.

In addition to the above, it is likely we will see updates to the following regulations and sections:

  • Installation of wiring in escape routes
  • Selection and installation of wiring cables
  • Outdoor lighting installations
  • Mobile and transportable units
  • Auxiliary circuits
  • Protection against electric shock

Who Will the Changes Affect?

Electricians, consultants, architects, surveyors and local authorities must be aware of the new regulations. Anyone responsible for the design, installation and maintenance of electrical wiring will be required to comply with the changes in Amendment 3.