On Wednesday, 6 May 2020 17:48:03 UTC+1, ARW wrote:
On 06/05/2020 10:12, tabbypurr wrote:
On Tuesday, 5 May 2020 12:36:53 UTC+1, Dan S. MacAbre wrote:

I've a question about the earthing connections on our domestic plumbing.
I can see that there is a wire in parallel to our water meter, but I'm
not sure that this can be the main earth because the supply pipe is
plastic. I can also see a wire going into the wall under the sink, so
my assumption here is that it mainly uses the electrical earth. But
there are speedfit connectors under there, which I expect are not
conductive, so there are parts (e.g. pipes feeding taps) that are
isolated from the rest. I'm not worried about this (although perhaps I
should be?), since all this was supposedly done by professionals; but I
thought I'd ask here if every single section of pipe is meant to be
individually earthed, or if that would not really be practical. Does it
even make sense to earth, for example, braided tap tails?

What matters is that you've got an effective earth. Is there such a thing from the incomer next to the fusebox? If not, expect to truly need to sort it. If there is then the waterpipe connections are going to only be equipotential bonding, which is a minor safety matter.


If required then the absence of main equipotential bonding is a code 2
on an EICR.

Yet in terms of actual safety, the benefit is minimal.