Damn Earthing!

[SSE]

The house I am working at has been sheeted, filled etc and now the woman has decided she wants a whirlpool bubble bath in. There was already a supply in for something else that I can use as it's not needed now but still have a question. As all circuits are going to be rcd protected I was told there was no earthing required in the bathroom but on the installation instructions for the bath it says all conductive parts including hot and cold pipes on bath, metal supports etc must be earthed in no less than 6mm. The pipework in the house is done in plastic and copper and in the bathroom to the bath goes copper-plastic-copper at the taps. Do I need earth this or not?

 

[sjm]

If I were you I would contact the manufacturers and request clarification of their requirements and why. If they require main bonding or supplementary bonding.
As you say under the 17th supplementary bonding may be omitted if circuits are RCD protected, the disconnection times are met and main protective bonding is in place, so why would the manufacturers require it over the regs. Also supplementary bonding conductors are 4mm.
If they require main protective bonding why, because that happens where the services enter the equipotential zone doesn't it?

 

[alarm man]

Only metallic services entering the bath/shower room may be classed as extraneous conductive parts...once they are within the confines of the location they can no longer introduce an earth potential from outside the location so it matters not if they change to plastic. If supplementary bonding is required it should be carried out on the metallic services where they enter the location.As it is permissible to use a copper pipe as a supplementary bonding conductor,providing the pipe is electrically continuous up to the point where it enters the location, bonding can often be carried out in a more convenient location such as the airing cupboard.
Bonding has absolutely nothing to do with earthing pipes and taps....it is to prevent a potentially dangerous difference in potential between exposed conductive parts and extraneous conductive parts during fault conditions....the definitions of what constitutes an extraneous conductive part in the BRB is often poorly understood and leads to a lot of the confusion on bonding issues.

when i was at college we were taught earth from cu to bathroom and bond taps.toilet water pipe and radiator

 

[Deleted member 9648]

I've come across this before,I once saw a steel kitchen sink, the packaging had the words WARNING,THIS SINK MUST BE EARTHED.!!...obviously the manufacturers have no knowledge of the actual requirements.
Generally a bath/sink/radiators are not extraneous conductive parts unless they are fixed to metallic structural parts....the pipes supplying those items are likely to be extraneous conductive parts though ,and may require supplementary bonding if the 3 conditions to omit are not met.

 

[Deleted member 9648]

when i was at college we were taught earth from cu to bathroom and bond taps.toilet water pipe and radiator

They taught you wrong mate,I suggest you have a look at the actual requirements in the BRB,(701.415.2) and in particular the definition of an extraneous conductive part...(p24)

 

[alarm man]

They taught you wrong mate,I suggest you have a look at the actual requirements in the BRB,(701.415.2) and in particular the definition of an extraneous conductive part...(p24)

it was in the citb book 1988..i should sue.no wonder im now doing alarms

 

[Des 56]

Have a read of the IEE s very clear instructions, and then you will know whats required
Hep2O® - Electrical Earth Bonding of Plastic Plumbing Systems

Can someone please tell this thick headed moron ( thats me by the way)
How do you preview a post on this forum ?
I wont know if the link works,I cant seem to get to grips with the newness

 

[Sintra]

Hit the go advanced icon then the option for previewing will be at bottom.

 

[Spudnik]

Come on Des, keep up!!

 

[WayneL]

Have a read of the IEE s very clear instructions, and then you will know whats required
Hep2O® - Electrical Earth Bonding of Plastic Plumbing Systems

Can someone please tell this thick headed moron ( thats me by the way)
How do you preview a post on this forum ?
I wont know if the link works,I cant seem to get to grips with the newness

Just had a read, Des, looks very 16th to me.

Wasn't impressed with it, personally, - unless he's dumbing it down

 

[Des 56]

I kid you not Jason ,I am really struggling with it all
That was my first attempt at replying to a post for a while
Are they smiles after your reply or scowls Got it

 

[alarm man]

They taught you wrong mate,I suggest you have a look at the actual requirements in the BRB,(701.415.2) and in particular the definition of an extraneous conductive part...(p24)

page 68 of the citb electrcians book 1984 of which we were given,'in rooms conataining a fixed bath or shower supplementary bonding should be installed to reduce to a minimum the risk of electric shock in circumstances when the body resistance is low.the most common method is using bs951 clips' it shows bonding between all taps,rads,toilet water,shower and metallic waste pipes in a bathroom,we were then told run it back to the cu.my house was built in 84 and its exaclty that set up..

 

[WayneL]

Just had a read, Des, looks very 16th to me.

Wasn't impressed with it, personally, - unless he's dumbing it down

Ha ha - I've just realised it's a plumbing site - my question answered.

 

[Des 56]

Ha ha - I've just realised it's a plumbing site - my question answered.

Even Paul Cook will talk to those humans who talk and shovel shsh - t ( sorry for not swearing )

 

[SSE]

Have a read of the IEE s very clear instructions, and then you will know whats required
Hep2O® - Electrical Earth Bonding of Plastic Plumbing Systems

Can someone please tell this thick headed moron ( thats me by the way)
How do you preview a post on this forum ?
I wont know if the link works,I cant seem to get to grips with the newness

Thanks. According to that link "If some of the services are of metal and some are plastic, then those that are of metal must be main bonded" I take it that just means my main bond where its metal needs to be bonded, not everywhere where theres a metal pipe on that services, as it changes back and forth between metal and plastic?

 

[Spudnik]

I kid you not Jason ,I am really struggling with it all
That was my first attempt at replying to a post for a while
Are they smiles after your reply or scowls Got it

No worries mate.

Once you get the hang on it, its a piece of cake.