kitchen extention supplementery bonding

[supersead]

hi i have just had a kitchen extention built i have just been putting finishing touches in place and realised there is no supplementary bonding for the sink is this the norm now i done a bit of electrics many moons ago and always used earth the sink. by the way the sink is ceramic. thanks for reading

 

[ColJack]

suplementary bonding is only required in areas with a bath or shower now..

apparently you don't get wet enough just washing up... you have to be naked and soaked...

most good sparks will cross bond the pipes to each other and a metal sink, if they can find a spot on the sink to bond to... they stopped putting tabs on a while ago..

 

[supersead]

cheers for response

 

[securespark]

most good sparks will cross bond the pipes to each other and a metal sink, if they can find a spot on the sink to bond to... they stopped putting tabs on a while ago..

I consider myself a good spark & follow the regulations. I don't provide supplementary. Sink manufacturers don't put tabs on anymore because the regs changed. A bad connection is pointless, whatever your viewpoint on supplementary in kitchens.

Supplementary at kitchen sinks is frowned upon now. Parallel earth paths is one reason put forward. Paul Cook has some interesting explanations, but can't find his stuff just now.

 

[SparkyNinja]

Same here, always install supplementary across the hot and cold, but in recent years it has been made apparent that bonding the sink makes it an unnecessary return path which can cause more harm than good.. seeing that if a fault occurs on an appliance, the fault path would go through your body and to the sink if you are in contact with it, as the return path is likely to be bigger...


I'm still not sure... I think great big conductors in the kitchen should be bonded myself..

 

[bernardgreen]

This puzzles me too. The stainless steel sink is almost certainly electrically in contact with the water taps which are earthed via copper pipe work so the bonding of the sink is not going to be the only earth on the sink.

That said some taps will not provide an earth for the sink so the un-bonded sink is electrically floating. If a double insulated appliance ( no earth wire) is dropped into water in an un-bonded and un-earthed stainless steel sink there is no route for earth leakage current to trip the RCD so the sink could become live. At that point one hand on the sink and the other on something earthed like a cooker, radiator, earthed metal kettle could be fatal.

As there is going to be a route via the taps and pipes to provide an earth then bonding should be done. ( in my not so humble opinion )

 

[Adam_151]

Personally, I'd probably cross bond hot and cold to each other, (although its not required by BS7671), I wouldn't take it to anothing else though, I can certainly see the potential for it to make things more dangerous, not less if you start taking it back to the CU, or even just keeping it local and bonding into nearby circuits.