Hi, Do I need to Bond radiators and Pipe work in my bathrom and en-suite even if all circuits are protected by RCD's?
I read a document stating that if a reading of 1667 ohms or less is obtained when going from the pipe work to the earthing terminal of the circuits within the bathroom then no bonding is required.
Some of the Pipe work under the floor boards is plastic and then comes up through the boards copper.
If I do need to bond all rads and pipework do I run 4mm earthing to an earth terminal from a circuit (Lighting).
I've noticed that all pipes coming from my combi are bonded at the boiler,including the hot water supply which is then connected using plastic..

As you have RCD protection you do not need supplemental bonding, doubly so as you have plastic pipes.

PS I'd test the pipework to a good known earth, if there is a viable electrical path for some reason and there's power in the bathroom (sockets, shaver point or leccy shower), I'd bond the pipes to earth regardless of the regulations saying you don't need to - as earth faults don't read regulations!

Thanx for replies much appreciated...