"Earl Kella" wrote in message
...

"Christian McArdle" wrote in message
. net...
http://www.iee.org/Publish/WireRegs/...asticPipes.pdf

P.S.

The thrust of the document is to encourage the use of plastic pipework.
The
IEE believes that plastic pipework and the subsequent lack of earthing
potentials in the room is a safer environment than an bonded earthed
metal
one. If there have to be earthed potentials in the room, it is best that
they are the same, however, which is what supplementary bonding is
about.

Thanks for the replies, I should have mentioned that all my plumbing uses
copper pipe with plastic push-fit joints but I gather the answer is the
same.
....any pipework under the floor is effectively isolated by the
push-fit joint.

I don't think so. The IEE document is silent on the scanario of metal
pipework with plastic joints, but its recommendation not to earth bond metal
fittings connected by plastic pipework is based on the resistance of water
in plastic pipework providing a level of insulation such that bonding is not
required. However where you have metal pipework with plastic joints you only
have a few millimetres of water separating conductive lengths and the
resistance of the water can not be expected to provide anything like the
same protection as metres of plastic pipe, so in your case exposed metal
pipes in the bathroom _should_ be bonded.

I will take attitude that unless there is the remotest chance of a tap,
radiator etc. coming in contact with a live wire then there is no need to
earth it ...

AIUI the reason all-metal pipework should be bonded is that in _any_ house
with an electricity supply there is a remote risk of pipework being made
live. Of course a responsible installer would not install either cabling or
pipework in such a way that there was a substantial risk, but unforseen
circumstances can create such a situation and the bonding is there as a
safety measure (belt _and_ braces :-)


--
John Stumbles
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