Shock Likelihood at Switch.

Is the back of metal frontplate insulated somehow or is it exposed to the wiring within the backbox?


Does it have the Class II symbol?


Regards


BOD

What we have here is, IMHO, simply a difference of opinion.


I'd be interested in JP's view, but a Court would be interested to know (from an expert such as JP) what the range of reasonable opinion might be.


As I have said above, "if" is a very good word to use - lawyers use it.


So if a switch plate is not earthed, and if a live conductor comes into contact with it, and if somebody touches it ... my opinion is that there is a greater/less than 50% risk of ...


I would suggest that a compliant installation is presumed to be safe, but it is up to the responsible person to show that a non-compliant one is safe in the event of a disaster.

but it is up to the responsible person to show that a non-compliant one is safe in the event of a disaster.


IF it were safe, there wouldn't be a disaster Chris!


It therefore follows if there is a Court case, it has already shown that it was not safe..................


Regards


BOD

IMO, electrical installation is a trade activity and not really a design activity, although there may well be design involved. I would suggest that an electrician involved with basic installation follows the party line , that is NICEIC or NAPIT accepted rules of engagement . I'll get your coat....


Legh

Legally the test is 'is it reasonable to code this as a C3 ?' i.e. recommend but not force immediate improvements

or C2  'potentially dangerous, fix ASAP'


So then the next line is 'how would a reasonable electrician code it?' which has been the test of this discussion.

I think we'd all agree it is not immediate danger requiring the place to be locked off until remedied, though there is more than a consensus supporting C2, potentially dangerous.


So the punter has not been told  'fine and dandy, carry  on', but equally they have not been told ' fix this now, it could kill you tomorrow'


Given the fuzziness of some advice around  EICR codes,  and the fact we have not seen it - there may be other factors we do not know that make it more dangerous - damp floor, house full of nudists or fiddle fingered kids , rubber wiring perishing,  or less dangerous, upstairs wooden floor, no earthed objects nearby, PVC cable, only occasional use.. that could make a judgement call shift either way.

Yes it is not to regs, and in backside covering mode, I might err towards the tighter code, but I can see a case for not doing so, so long as it is made clear it is not right.

As others who have done it will agree, being an expert witness isn’t the easiest thing in the world, especially if the judge reads up on the subject! I was involved with an inquest a bit back, and with the help of BOD’s extensive Wiring Regs library, I was able to show that the installation did not comply with the regulations when it was installed - a TT system without either an RCD or VOELCB. BOD was able to furnish the appropriate pages from both the 13th edition (1963 amendment) and the initial version of the 14th, as I couldn’t determine which was the current version when the property was built. 


You could introduce the ESF guides as indicators of best practice, or perhaps detail that the manufacturer had fitted an earth terminal that was not connected. Although electricity was not his subject, I felt that the judge read my report from cover to cover, plus the parts of the standards I had referred to. The questions I was asked were certainly relevant and researched. 


Regards,


Alan.

Although a metal wall switch without a cpc is a single fault to danger, I think it is mitigated by (1) there is little movement  - the switch mechanism itself moves, but the overall accessory is firm - unlike a ceiling pendant for example where someone changing a bulb or shade might cause all sorts of yanking and chafing. So for example even if a wire was loose in a terminal, it's unlikely to ever move and touch the exp-c-p. (2) Any body contact is likely brief - there's nothing to clench onto if finger muscles go into spasm, and it's relatively hard to fall onto. Unless there are factors in the other direction, I think its reasonable to argue for a C3 in those circumstances.

I opened up a pattress box double pole switch controlling an immersion heater and the CPC had fell out of its terminal, it is not unusual to find such issues.


If the live falls out of its terminal within an un-earthed metal light switch it may be more than the lights that go out.


Andy B.