Surge Protection – BS7671 18th Edition

On the 1st January 2019 the UK introduced a new version of BS7671 – also known as ‘The 18th Edition of the IET Wiring Regulations”. This holds dual status as both a British Standard document and a legally enforceable regulation and it has its origins in the international standard IEC 60364.

Essentially there are now five criteria where Surge Protection Devices (SPD’s) are mandatory, the standard is quite clear it states “SPD’s shall be fitted if”:

1. The structure is fed via an overhead line – in which case a lightning arrest type 1 SPD is required
2. Where an overvoltage could lead to serious injury or loss of human life
3. Where an overvoltage could lead to interruption or damage to public service and/or cultural heritage
4. Where an overvoltage could lead to disruption to any commercial or industrial activity
5. Where an overvoltage could affect large numbers of collocated individuals.

If any of these five criteria apply to your structure or project then an SPD is mandatory, if they are not applicable then the regulations say that you must still carry out a risk assessment to determine if SPD’s are required.

The risk assessment is intended for electricians to complete with assistance from their client, but it is a long and complex procedure, the regulations state that if you choose not to carry out the risk assessment then again you must install SPD’s.

If you require any further information please contact us.

Lightning conductors installed, repaired or tested at: