18th Edition of the Wiring Regulations – Handling Departures

With the publication in July 2018 of the latest edition of the IET Wiring Regulations BS 7671, electrical specifiers, designers, suppliers and installers are busy getting to grips with the changes in time for the formal transition at the end of 2018.

While early 2019 may see the UK departing from the European Union, there are other departures of an electrical nature that will become important to understand and handle properly when applying the new edition of the Wiring Regulations.

18th Edition of the Wiring Regulations – Handling Departures

With the publication in July 2018 of the latest edition of the IET Wiring Regulations BS 7671, electrical specifiers, designers, suppliers and installers are busy getting to grips with the changes in time for the formal transition at the end of 2018.

While early 2019 may see the UK departing from the European Union, there are other departures of an electrical nature that will become important to understand and handle properly when applying the new edition of the Wiring Regulations.

 | Basec Construction Electrical Installation

What are departures?

Departures are deliberate decisions not to fully comply with the requirements of the Wiring Regulations. End users and specifiers may not be aware of the current extent of the practice, but this will become clearer under the new arrangements, which require designers to make an assessment and declare that the resulting degree of safety is no lower than with strict by-the-book compliance. The fact that a departure has been made must also be recorded on the installation certificate.

What does this mean for cables?

For cables, this means that any use of a custom, non-standard, or partially compliant cable must be declared and assessed. If regular British or harmonised standard cables are used in accordance with the requirements, there is no departure, so the installation may be documented, tested signed off in the normal way. However, if a cable is used that is outside the normal range of standards then new responsibilities kick in.

The designer must assess the product for the application in which it is intended to be used, making sure that the resultant degree of safety is not compromised. For example, if it were proposed to use a non-armoured cable buried in the ground, instead of a regular armoured cable (for example to BS 5467), then additional measures to protect the cable from digging risk would need to be applied to achieve the same degree of safety.

The Regulations set the same requirements for novel products. For cable, this might be special multicore cables intended for use in modular wiring or lighting systems. Any novel cable used will be expected to have been designed, manufactured and tested to the same requirements as a regular standardised cable, if the same degree of safety is to be achieved.

How will the new wiring regulations affect stakeholders?

Risk assessment will become a more important aspect of designers’ and installers’ work as a result of this new requirement. This will always require detail of the installation conditions and any external influences the cable may be subject to.

For the specifier, end user and other stakeholders, this should mean greater transparency in cases where product substitutions are proposed and a decision trail where novel solutions are adopted. This should provide greater peace of mind that unsuitable products have not been used.

To assist manufacturers in meeting the new requirement, BASEC offers a Certificate of Assessed Design (CAD) approval service for novel cable designs. This integrates the specification, testing, usage and risk assessment requirements into one document that can be directly referred to by the specifier, designer or installer.

Author: Dr Jeremy Hodge

Editor: Jenn Catterall MSc