Experts are here to help

During our recent online Branch Updates, Members submitted a range of questions for our Technical Advisers to tackle. Here is a small selection of the queries we received, along with the answers from our experts…


respect to an Electrical Installation Condition Report (EICR) carried out by another electrician. T is always throws up questions and queries on the code attributed.

Firstly, we need to understand that during the inspection process the ‘Inspector’ should use their skills, knowledge and experience as the competent person to decide on the classifi cation code to be used. At the end of the report THEY

EYwill be the

one signing the report to accept full responsibility for the content and most importantly the accuracy of the report. Yet we still see the classifi cation coding being harshly applied in some instances.

As Technical Advisers, we will always recommend that all inspectors refer to the Guide to EICRs issued by Electrical Safety First. The example of observations

I’ve been asked by several clients and potential clients to carry out remedial works in

found and potential codes has been discussed and agreed by several organisations, including SELECT, so we have an industry-wide template. As soon as we are back out on the road, we will be carrying handy-sized copies of this, but in the meantime download a copy at


be provided with surge protection devices (SPDs)? Members regularly ask if installations should be provided with SPDs. To answer the question, let’s start with Regulation 443.4, which is on page 101 of BS 7671:2018, and says that protection against transient overvoltages shall be provided where the consequence caused by overvoltage could: ● Result in serious injury or loss of life to humans, or ● Result in interruption of public services and/or damage to cultural heritage, or ● Result in interruption of commercial or industrial activity, or ● Aff ect a large number of co-located individuals. For all other cases a risk assessment according to Regulation 443.5 shall be performed in order to determine if the protection against transient overvoltages is required. This can also be found on page 101 of BS 7671:2018. Here are a few notes about the risk assessment: ● CRL=fenv/(LpxNg) – there is nowhere on current certifi cation to record this calculation to show you have completed the risk assessment ● Fenv – an environmental factor selected according to table 443.1, page 103 of BS 7671:2018 ● Lp – the risk assessment length in Km calculated using Lp=2 Lpal + Lpcl + 0.4 LPAH+0.2 LPCH(KM) on page 103 of BS 7671:2018 ● Ng – the lighting ground fl ash density (fl ashes per km2

per year)

relevant to the power line and connected structure. See fi gure 44.2, page 102 of BS 7671:2018. If the risk assessment is not performed, the electrical installation shall be provided with protection against transient overvoltages, except for single dwelling units where the total value of the installation and equipment does not justify such

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CABLEtalk APRIL/MAY 2021 37

To SPD or not SPD, that is the question: Should installations always

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