SPD in commercial offices

John-SJW · May 28, 2021

Surge protection is now semi-mandatory in domestic (there are get out clauses).
Is SPD mandatory, or semi-mandatory, in commercial offices?

dodger421 · May 28, 2021

I can tell you that the same process should be carried out as for domestic premises, but that’s simply from following the regulations and we’ve already established you’re not keen on that.

To clarify, that’s 443.4 where single dwellings are excepted from the requirements to perform a risk assessment. You need to carry out a risk assessment or if you decide not to carry out a risk assessment you need to provide transient overvoltage protection.

timhoward · May 28, 2021

I recently had a similar question. Part of my journey towards the answer in my particular case was this short article:

SPDs Where and When?

Within the 18th Edition as far as SPDs and protection against transient overvoltages are concerned there is no need to provide protection for single dwelling units (safe to assume they mean domesti…

tinyurl.com

westward10 · May 28, 2021

Can we not turn this thread into a --- for tat argument. Some posts have been removed.

dodger421 · May 28, 2021

westward10 said:
Can we not turn this thread into a --- for tat argument. Some posts have been removed.

Fair. Sorry for my part. And sorry to John for the comments.

i=p/u · May 28, 2021

So what the guidance is saying Johnboy, do a risk assessment of clients electronic equipment (cost)and ask them isit worth it or not.

They should sign it too.

Doomed · May 28, 2021

Got caught out on my NIC assessment in 2019 for not fitting them on a commercial job.

i=p/u · May 28, 2021

Did they make u go back and fit it?

Doomed · May 28, 2021

No, just stearnly told us to do risk assessments in future on an individual basis (ie, for the cost and hassle of doing the assessment and getting approval from the client NOT to fit it its just easier to go ahead and fit surge and charge a bit more for the job)

pc1966 · May 28, 2021

I agree with @Doomed
In many cases if you cost the time to perform the risk assessment and go through the options with your client (including getting the value of equipment they have that is susceptible to damage, and the cost implications of lost business due to damage-induced down-time, etc) it will cost about the same as fitting a type 2 SPD anyway!

Edited to add: If they have a lightning protection system to need type 1 SPD then it has to be fitted anyway. Though some remote sites with lots of lightning activity might be better served with a type 1 so it lasts longer.

i=p/u · May 28, 2021

What happens if their electronic equipment still goes bang in a lighting storm

pc1966 · May 28, 2021

i=p/u said:
What happens if their electronic equipment still goes bang in a lighting storm

Their problem, as you have done your bit.

Most electronics should survive at least the CAT-II sort of surges, but some are simply crap, and others are also vulnerable to damage though data lines (cable TV coax, phone line, etc) so would need separate protection.

You can harden electronic installations to survive a direct hit and keep going, but not domestic installations for sure!

i=p/u · May 28, 2021

Have other services as phone, cable tv adopted this too?

pc1966 · May 28, 2021

i=p/u said:
Have other services as phone, cable tv adopted this too?

Don't know about cable TV, but traditional phone lines always had SPD at the master socket and there are standards for the sort of spikes that telecoms stuff should handle.

Though I suspect that has gone from newer systems. Probably BT, etc, treat the modems as disposable - they often don't update the crap software anyway!

pc1966 · May 28, 2021

From the archive of "here is one prepared earlier" we installed a system in Italy in 1995 and upgraded its computers and radio part in 2005. In 2019 I went out to repair it as they said it stopped working in one of its frequency bands, but the antenna was still tracking and working in the other.

Only later did they admit that it happened at the same time as a lightning storm.

Then when I got there and took down the front-end (bit that sits at the focus of a dish-style antenna) to replace the failed low-noise amplifier I found this melted spot where it actually had been hit: