Is the UK the only country that continues to permit and deploy TN-C-S earthing systems?

What labour?  Having checked with the manufacturer's web site, my charger has a dedicated chip on its motherboard.  The installer doesn't have to do anything to make it work.  No earth rod is required.

Alan B said:

Going through this discussion one of my takeaways is that no one has quoted any serious injury or death from open pen faults in the UK.

As this link discusses, deaths due to low voltage electricity of any cause are relatively low in the UK: https://elecsafety.co.uk/the-risks-in-underestimating-the-danger-electricity-poses-in-the-workplace/

The way the statistics are gathered, there is no way of telling whether any of those were in any way due to PME issues of any kind.
I don't believe there is any way to access non-fatal shock statistics categorised in a way that might show shocks from PME occur ... but it's a well-known phenomenon about the "shock from the garden tap" even if there are no statistics to back it up.

Since the Government have highlighted the issue (see my earlier post in this thread) along with other industry guidance including ENA Engineering Recommendation G12/5 (and its predecessors), it's not a simple matter to "back-peddle" on this subject.

Indeed, the Health & Safety Laboratory Report of November 2012 Charging of Electric Vehicles at Domestic Dwellings Using Protective Multiple Earthing (PME) - Risk Analysis states (main findings, page 4) that, whilst the risks associated with PME supplies and EV charging is 'broadly acceptable' (at least for domestic charging) based on conservative estimates and assumptions, the findings also state: "With this level of risk additional control measures to reduce risk should be implemented if it is reasonably practicable to do so, but a less onerous justification would be required than if the risks were to fall in the higher risk ‘Tolerable’ region."

So perhaps in this case, absence of [firm statistical] evidence is definitely not evidence of absence [of risk of a potential fatality].

gkenyon said:

As this link discusses, deaths due to low voltage electricity of any cause are relatively low in the UK:

I am surprised that the mortality rate is so low.

One f the problems (if one can call it that) is that people get electrocuted one at a time, so there might just be a snippet in the local paper at most. By contrast when bridges or buildings collapse, or aircraft crash, it makes the headlines even though the risk may be significantly smaller. 

Chris Pearson said:

I am surprised that the mortality rate is so low.

Actually there are very few electrocutions of any kind in the UK compared to almost any other 'common' cause of possible death that is present in nearly every household. When part P was coming in, and again when it had its ten year review, I looked into this, and found that it had had no significant statistical effect, unless (as at least one body was doing) you cherry picked particularly bad years before to compare with good years after. Otherwise all you see is a falling accident rate that has stopped falling.  But the data is very noisy, as you are looking at a few tens of fatalities per year in a bad year, and single figures in a good one, and when you dig into the details of each accident, which is quite practical, given the low numbers, some are so weird they should really be discounted from the total as being a situation that will never happen again.

There are more fires, but mostly due to appliance and extension lead faults not wiring.

There are figures for lost neutral events, as per the report above but most result in tingles, cursing and maybe some damaged kit. The DNO helplines are told to prioritize calls that sound like this and they tend to get sorted quite fast.

Mike.

I would further add that (if memory serves me correctly) the risk level discussed in the HSL report was estimated at less than 1 in a million per year, with each possible risk event coinciding with someone touching a vehicle on charge, coinciding with an open-PEN event (the assumption being any open-PEN event is a possible fatal shock).

We have less than 1 million chargers in the UK at present, and we know that not every open-PEN event would lead to a fatal shock for a number of reasons ... at the same time, there is definitely anecdotal evidence of electricians and charge point / OPDD manufacturers reporting possible PEN faults - which turned out to be real PEN faults - because of OPDD operation. (Just to ensure a balanced argument, there are also issues where unwanted operation of OPDDs has led to reporting of faults that didn't exist!)

But, all this goes to show that a serious shock or fatality due to an open-PEN event is entirely possible in the UK (say every couple of years or so) with the number of charging points we have now (although still very unlikely as the HSL report says), and to my mind, if some form of protection might save a lives, should we not fit that?

Unfortunately (or fortunately) with the provisions in BS 7671, and charging points either being TT, or having OPDDs or some other form of mitigation, the only statistics we will hopefully gather are "no further evidence of shock from EV charging".

gkenyon said:

PEN fault protection is being actively considered in the Republic of Ireland

That is interesting. Considered by whom? 
IS10101-2020 Amd 1 2024, like its predecessor, and unlike BS7671, does not disallow TNCS to caravans or for boat hook-up in marinas. The only requirement is that the final circuits should not include a PEN conductor. Strangely, in 711 Exhibitions Shows and Stands, where a TN system is to be used, it must be TNS, and makes no distinction between inside and outside. 
In 722, Supplies for EVs, similar to 708 and 709, there are no requirements to mitigate against open pen other than to specify that the circuit supplying the EV should not include a PEN conductor (circuit is defined and does not include that part belonging to the DNO).

You guys are blessed to have the one standard to cover all parts of mainland UK. When you live in Ireland and work both sides of the border, you need to be on your toes to be aware of the differences in the two standards! 

lyledunn said:

That is interesting. Considered by whom? 

Relying only on what is public knowledge, being published, if you have a look at the Technical Committee in IET01:2024, it might become apparent.

lyledunn said:

You guys are blessed to have the one standard to cover all parts of mainland UK. When you live in Ireland and work both sides of the border, you need to be on your toes to be aware of the differences in the two standards! 

Agreed, although we do have 3 sets of Building Regulations to contend with, that don't always see eye-to-eye.

(if memory serves me correctly) the risk level discussed in the HSL report was estimated at less than 1 in a million per year

Also from memory, I think another way of seeing the same risk (given the number of consumers and one fault can affect several consumers) is something in the region of 1 open-PEN fault per day, across the UK.

   - Andy.

in the region of 1 open-PEN fault per day,

To be set against a background UK level about ten traffic fatalities and ten times that crash injuries leading to hospitalization, and of course up to 3-4 thousand natural illness type fatalities per day, rather more in winter, but less in summer, mostly in the older age groups.
Important to put various sorts of risk into perspective.
Mike

mapj1 said:

To be set against a background UK level about ten traffic fatalities and ten times that crash injuries leading to hospitalization, and of course up to 3-4 thousand natural illness type fatalities per day

Happily, you seem to be out of date, Mike. Rather fewer than 5 deaths daily.