Earthing gas and water

[robertukarch]

Hi

First picture shows my gas pipe earthed just by the meter, with a safety connector attached to a G&W earth cable. I am 99% confident this earth will be good because I don't think it has been touched since my flat was re-wired by a qualified sparky, maybe 5 years ago.

Question - Since a visual inspection cannot give me 100% assurance that this is actually functionally earthed (that is to say, in terms of actual physics, it is doing what it is intended to do) - Is there any way I can safely test this myself?

The second picture shows my mains water where it enters into my flat. The pipe to the far left going out of the building is copper, it has been painted white. So the arrangement is, from L to R, copper -> plastic coupler -> copper -> plastic mains stopcock -> copper -> pressure valve -> copper pipework extending to kitchen sink area

I think the plastic stopcock was installed after my flat re-wired; I think when the re-wire was carried out, the stopcock in place was a traditional brass tap type.

Questions - Should the copper to the left of the stopcock be earthed?
Should the copper to the right of the stopcock be earthed?

The pipe running vertically in the second picture is the same gas pipe as shown in picture 1, which I believe is earthed.

If the water copper should be earthed, then would an acceptable solution be to use safety connectors to directly connect the water copper to the adjacent gas pipe? This would be a very short cable run, and I presume it would work, but I am not sure if there are risks that I'm not aware of with this approach, or if every earth fitted has to run back to the MCB.

Many thanks for any advice given, which is much appreciated.

 

[newfutile]

As an electrician i would test to see if the pipe is what we call an extraneous conductive part, this requires an insulation resistance tester .
also the earth wire would not go to an mcb but to the MET main earth terminal. It may also be connected to earth via the boiler and the gas pipe. Also the cpc to the boiler will have some effect on any measurments taken . This is not really a DIY job.

 

[binky]

Plastic pipe fittings are a nuisance. They insulate, but it can only be established how well by testing. Bonding is to prevent a different earth potential being introduced from outside the property. So in your case I would say a bond to the painted part of the pipe might be needed, as those plastic fittings are very short in length.

Locked to prevent being resurrected (again)