Chrome EV shower pipes bonding all tiled...

[Just]

Hi, I have a situation with nice chrome pipes going to a external shower valve in a small shower room connected by copper pipe. I can't get under the floor to bond and I wouldn't be able to get access to the connections in the future. All tiled. I may be able to bond in another room but then I would be too far away from the item in question. Also other than a downlight I have no CPC near. What I have in mind is ugly, any ideas other than bond both pipes and go up the tiled wall to the loft to the cpc of the downlight circuit, or drill through behind the valve and chase out in the other room to the loft?
There is also a rad in the bathroom with pipes bonded together but not linked into a CPC. It looks as though there is a 10mm cable back to the MET linking other but not all metal, if all is linked is this sufficient or must it go to a circuit cpc as I can't see a good route for the bonding. An easy way would be to drill through where there is a socket in the bedroom which is also RCD'd or is this a conduit job up the wall to the pullswitch in the bathroom?
Cheers

 

[Deleted member 26818]

You can place the supplementary bonding outside the shower room, preferably close to the point of entry.
However supplementary bonding can be omitted, if the circuits of the location meet the required disconnection times, are RCD protected and the installation has compliant main bonding.

 

[High Tower]

Spin beat me too it

 

[Sintra]

It is not always necessary to cross bond pipes if for instance both pipes go into a monoblock tap or shower as this will effectively do the job for you.


Sent from my iPhone using Tapatalk.

 

[Just]

Yes Spin but all extraneous metalwork still need to be connected to protective equipotential bonding and so back to the MET. My problem is the tiled floors and reluctance to put a clamp on the chrome pipes. I will still need to bond but I can't find the reg that states distance from bond clamp to metalwork to allow me to bond outside the room other than 'preferably close to the point of entry of extraneous conductive parts into such rooms' 701.415.2 Seems a bit vague and I would need to have the clamp visible in the other room and therefore fit it to a rad?

 

[High Tower]

If there is a rcd fitted and main bonding is in place there is no need to bond the shower!!

 

[Deleted member 26818]

Yes Spin but all extraneous metalwork still need to be connected to protective equipotential bonding and so back to the MET. My problem is the tiled floors and reluctance to put a clamp on the chrome pipes. I will still need to bond but I can't find the reg that states distance from bond clamp to metalwork to allow me to bond outside the room other than 'preferably close to the point of entry of extraneous conductive parts into such rooms' 701.415.2 Seems a bit vague and I would need to have the clamp visible in the other room and therefore fit it to a rad?

Have you determined that the metalwork is extraneous?
Have you determined that it is not effectivly connected to the protective equipotential bonding?
How have you determined the effectivness of the connection to the protective equipotential bonding?

 

[Just]

Okay High Tower, that really would suit me fine and I'm not trying to be difficult but according to the regs..701.415.2(iii) 'SEB may be omitted where all of the following conditions are met:1) ADOS..etc 2) RCD etc 3) 'All extraneous conductive parts of the location are effectively connected to the protective equipotential bonding according to Reg 411.3.1.2' .So why don't I need to bond the shower?

 

[Deleted member 26818]

You first have to determine whether the metalwork for the shower is extraneous, and whether it is effectively connected to the protective equipotential bonding.
This is achieved by conducting a continuity test between the metalwork and the MET.

 

[Just]

Hi Spin, other than the pipework connecting to the main water bond at entry to the house there is no 'connection'. I thought there needed to be bonding close to the part which is why there is talk of 'close to point of entry of extraneous parts into rooms. There may be a an effective connection through pipework to main bond but when my friend the plumber comes in and does a little bit of work downstairs in plastic, I doubt he's going to bond the shower?!

 

[High Tower]

maximum impeadence of the shower pipework with a 30ma rcd is 1667ohn, the shower would have to be made of cardboard to exceed that, or the met in a different house all together lol

 

[Deleted member 9648]

Hi Spin, other than the pipework connecting to the main water bond at entry to the house there is no 'connection'. I thought there needed to be bonding close to the part which is why there is talk of 'close to point of entry of extraneous parts into rooms. There may be a an effective connection through pipework to main bond but when my friend the plumber comes in and does a little bit of work downstairs in plastic, I doubt he's going to bond the shower?!

You need to look at the definition of an extraneous conductive part in the BRB....the bit which says "liable to introduce a potential,usually earth"...is the key part.
I think you are confusing "earthing" pipes with bonding. The incoming water service is main bonded at the point of entry because it introduces an earth potential from outside.Once the pipe is inside the building it can no longer introduce an external earth potential so it does not matter how much plastic mr plumber installs,the hazard has been dealt with at the point of entry.
A bath/shower room is a special location and supplementary bonding may be required to extraneous conductive parts within that location...that is metallic services which may introduce an earth potential to that location. It is up to you to decide if those pipes are extraneous conductive parts,if they are they can usually be supplementary bonded outside the location as long as the pipes are electrically continuous to within the location....remember once they are in the location the hazard has been dealt with and it matters not if they then go to plastic. You are not earthing the pipes,you are bonding them.
A measured resistance of <1667 ohms between extraneous conductive parts and conductive parts within the location where all final circuits are 30ma RCD protected will meet the requirements.

 

[High Tower]

This is like pulling teeth!