Is it compulsory to put a SPD in a consumer unit?

This Q & A is one of the thousands posted in our Technical Expertise area and answered by our Voltimum Experts.

Question:

Is it compulsory to put a SPD in a consumer unit? 

Answer:

NICEIC Technical Expert

Within regulation 443.4 it states that SPD’s shall be installed where the consequences caused by overvoltage could:

1. result in serious injury to, or loss of, human life, or
2. result in interruption of public services and/or damage to cultural heritage, or
3. (iii) result in interruption of commercial or industrial activity, or
4. (iv) affect a large number of co-located individuals.

In all other cases, except for a single dwelling a risk assessment, A risk assessment to determine the Calculated risk level (CRL) will need to be carried out in compliance with regulation 443.5. Where the CRL result is greater than 1000 protection against overvoltage’s is not required.

Within regulation 443.4 there is an exception for a single dwelling and therefore it is our opinion that whilst there is typically no specific requirement to fit overvoltage protection within a single dwelling (Surge Protection Devices), it is important that the designer of the installation discusses with the client, the potential merits of providing such overvoltage protection.

An example of this may be where the value of the installation and equipment therein, is considered by the client to justify the cost of providing such protection.