earthing a kitchen sink


On the new sink which I just bought I am instructed that it must be earthed, certainly the sink in my utility room is so earthed - although the old sink which I just removed from the kitchen wasn't.
While I understand the legalities, I cannot for the life of me see that earthing the sink decreases risk. If someone picks up a badly earthed kitchen item with a "live" casing, touching the earthed sink will give a good path to ground through the body. If the sink was insulated from earth, there would be no such path.
What's the logic of this earthing, just out of interest? -- Jim "a single species has come to dominate ... reproducing at bacterial levels, almost as an infectious plague envelops its host" http://tinyurl.com/c88xs
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There's no requirement for equipotential bonding in a kitchen at all. It is often fitted though, particularly around the sink. As you correctly point out, there are cases where the bonding would make a fault more dangerous, but there are also cases where it makes it safer -- it's a difficult call, and up to you. It's now generally thought to be a bad idea where plastic piping has been used, as 0.5m of plastic piping, even with tap water in it, is effectively an insulator, and in this case having the sink insulated rather than grounded is safer. If you have a metal sink and/or metal taps and pipes, I do fit equipotential bonding, which at least prevents some fault generating 240V between the taps, or between a tap and the sink.
--
Andrew Gabriel

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writes:

Sounds like your a Sparky Andrew?
Are you registered for Part P yet?
Bruno
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No on both counts. ;-)
My reading of the trade press is that most sparks are still not intending to register for Part P, and are either: a) ignoring it b) decided to retire if they were near retirement age c) switched to commercial work only.
Part P will probably just push most domestic electrical work on to the black market, which is the exact opposite of what it was intended to do. That's the inevitable effect of pushing though very bad legislation of this form, which was never required in the first place.
--
Andrew Gabriel

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Just like CORGI, all the good guys have given up registration
--
regards
dave batter
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