Earthing the gas supply pipe into the house

[JohnW2]

It is permitted to use a water pipe as the bonding conductor for the gas pipe (but not vice versa).

That's always made me 'wonder' a bit! ISTR that there are some qualifications, but (if the conditions are satisfied) it theoretically means that one can bond a water supply anywhere one likes, even a long distance from the point of entry into the building, by arguing that most of the pipe between the point of entry and the point of bonding was being used as a 'bonding conductor'.

Kind Regards, John

 

[EFLImpudence]

It is permitted to use a water pipe as the bonding conductor for the gas pipe (but not vice versa).

That's always made me 'wonder' a bit! ISTR that there are some qualifications, but (if the conditions are satisfied) it theoretically means that one can bond a water supply anywhere one likes, even a long distance from the point of entry into the building, by arguing that most of the pipe between the point of entry and the point of bonding was being used as a 'bonding conductor'.

Possibly theoretically as (you know) the pipe has far lower resistance than the conductor.

I presume that to obviate the need to verify and maintain its continuity in the future bonding at the entry (farthest point?) is required.

 

[JohnW2]

Possibly theoretically as (you know) the pipe has far lower resistance than the conductor.

Quite so - so as long as the copper pipe run remains in place (and free from any 'sneeked in' plastic bits or fittings), it is, as you say, actually better than the usual G/Y bonding conductor.

I presume that to obviate the need to verify and maintain its continuity in the future bonding at the entry (farthest point?) is required.

You say "required" but, as above, (and as you imply) that doesn't seem to necessarily be the case. As far as I can make out, provided that one 'verifies continuity' (very easy) and 'precautions are taken against removal' (a label or three?), 543.2.6 allows that the majority of the pipe (back to close to the point of entry) can be regarded as a bonding conductor. That certainly would be an easier solution than the alleged problems (or, at least, inconveniences) of routing a G/Y cable that we often hear about.

Kind Regards, John

 

[EFLImpudence]

You say "required" but ...

In that the requirement is for connection 'at the point of entry'.

I can see no objection to what you are saying.

For example:
A water pipe enters at one side of the premises and happens to run across to the other side where it passes the MET.
You bond in the accepted manner and the conductor runs along the pipe to the MET.
Say you also connected the conductor to the pipe near the MET. Is the remainder of the conductor back to the point of entry doing anything useful?

 

[JohnW2]

You say "required" but ...

In that the requirement is for connection 'at the point of entry'. ... I can see no objection to what you are saying. For example: A water pipe enters at one side of the premises and happens to run across to the other side where it passes the MET.

... which is a situation we are quite often asked about ....

You bond in the accepted manner and the conductor runs along the pipe to the MET. Say you also connected the conductor to the pipe near the MET. Is the remainder of the conductor back to the point of entry doing anything useful?

Exactly (I'm taking that question as rhetorical!). However, I don't think I've ever seen an OP here (or anywhere else) being given that advice when, in such a situation, (s)he has said that it would be very difficult to run a (G/Y) bonding conductor back to the point of entry, have you?

Kind Regards, John

 

[EFLImpudence]

No but we have to be careful giving advice to DIYers and the regulations do categorically state 'at the point of entry'.

It is not like you or me being satisfied that it is safe and able to check after a plumber's visit.



Do you consider what you are suggesting is that the water pipe is satisfactorily bonded or that the pipe is its own bonding conductor?
Is there a difference?

After your reply a follow up question (tomorrow, tfb).

 

[JohnW2]

No but we have to be careful giving advice to DIYers and the regulations do categorically state 'at the point of entry'. ... It is not like you or me being satisfied that it is safe and able to check after a plumber's visit.

I think we can probably agree that it would be safe (at least as safe as with a long G/Y bonding conductor) at the time that you or I installed the bonding. As often asked, to what extent do we have to try to anticipate what other people may do in the future? Let's face it, after that plumber's visit, bonding that had been connected 'at the point of entry' may have magically become 'disconnected'! In both cases, all we can do is to put warning labels around the place, and hope that the plumber can read!

In practice, of course, the main issue may be well not relate so much to subsequent plumbers' visits as electricians' visits. What proportion of electricians undertaking an EICR do you think would be happy with bonding that was connected to the pipe distant from the point of entry? At the least, one would probably have to stick an 'explanatory note' to the CU, MET and/or point of connection of the (G/Y) bonding conductor - otherwise I suspect that there is a very high chance that it would get 'coded'!

Do you consider what you are suggesting is that the water pipe is satisfactorily bonded or that the pipe is its own bonding conductor? Is there a difference?

I don't see any difference. Let's face it, if one really wanted to be silly (but to make the point) one could run a 'bonding conductor' consisting of a length of copper piping (with electrical continuity throughout) from the MET to to the incoming water pipe at the point of entry, couldn't one?

After your reply a follow up question (tomorrow, tfb).

Fair enough. Sleep well!

Kind Regards, John

 

[EFLImpudence]

As often asked, to what extent do we have to try to anticipate what other people may do in the future? Let's face it, after that plumber's visit, bonding that had been connected 'at the point of entry' may have magically become 'disconnected'! In both cases, all we can do is to put warning labels around the place, and hope that the plumber can read!

That's true but the only reason I can see for stating 'point of entry'.
Nowhere is it said that bonding may be applied elsewhere - other than 'where practicable', would that cover what we are saying?.

In practice, of course, the main issue may be well not relate so much to subsequent plumbers' visits as electricians' visits. What proportion of electricians undertaking an EICR do you think would be happy with bonding that was connected to the pipe distant from the point of entry?

Not many but that doesn't make something wrong.

At the least, one would probably have to stick an 'explanatory note' to the CU, MET and/or point of connection of the (G/Y) bonding conductor - otherwise I suspect that there is a very high chance that it would get 'coded'!

It would.

[I have just had two boilers 'safety checked'. On both it has been stated that the MEB is not within 600mm of meter. Both meters are 'miles' away outside - very good family firm.]

Do you consider what you are suggesting is that the water pipe is satisfactorily bonded or that the pipe is its own bonding conductor? Is there a difference?

I don't see any difference.

It may be splitting hairs but is it considered that the bonding should be applied at the origin or cause of any pd?
If so, then it must be considered to be its own bonding conductor.
This is not allowed for a gas pipe yet 'where practicable' also applies.

Let's face it, if one really wanted to be silly (but to make the point) one could run a 'bonding conductor' consisting of a length of copper piping (with electrical continuity throughout) from the MET to to the incoming water pipe at the point of entry, couldn't one?

If you mean purposely laid parallel to the water pipe then, yes.

 

[JohnW2]

As often asked, to what extent do we have to try to anticipate what other people may do in the future? Let's face it, after that plumber's visit, bonding that had been connected 'at the point of entry' may have magically become 'disconnected'! In both cases, all we can do is to put warning labels around the place, and hope that the plumber can read!

That's true but the only reason I can see for stating 'point of entry'. Nowhere is it said that bonding may be applied elsewhere - other than 'where practicable', would that cover what we are saying?.

Isn't is all down to words/semantics? Say one has a water supply pipe which is bonded to MET (with G/Y) 10m from the point of entry. If one chooses to define, say, the first 9.6m of the pipe (starting from the MET end) as a 'bonding conductor' (which is seemingly allowed), then the incoming supply pipe is being 'bonded' 400mm from the point of entry, just as if it would be if there were a 9.6m length of 10mm² G/Y, isnt' it?

In practice, of course, the main issue may be well not relate so much to subsequent plumbers' visits as electricians' visits. What proportion of electricians undertaking an EICR do you think would be happy with bonding that was connected to the pipe distant from the point of entry?

Not many but that doesn't make something wrong.

Not wrong, no, but that situation would create a major nuisance ... as you go on to say...

At the least, one would probably have to stick an 'explanatory note' to the CU, MET and/or point of connection of the (G/Y) bonding conductor - otherwise I suspect that there is a very high chance that it would get 'coded'!

It would.

Do you consider what you are suggesting is that the water pipe is satisfactorily bonded or that the pipe is its own bonding conductor? Is there a difference?

I don't see any difference.

It may be splitting hairs but is it considered that the bonding should be applied at the origin or cause of any pd?

Sure, and that obviously makes sense. However, as above, if one considers most of the internal pipe to be a bonding conductor then one is bonding the incoming pipe 'at its origin', isn't one? As you go on to say

... If so, then it must be considered to be its own bonding conductor.

This is not allowed for a gas pipe ...

It isn't - presumably because of concerns about potentially high currents being carried by a pipe containing gas. However, if you accept the arguments above, there is presumably no reason why a water pipe could not be used as (most of) the 'bonding conductor' for an incoming gas pipe.

Let's face it, if one really wanted to be silly (but to make the point) one could run a 'bonding conductor' consisting of a length of copper piping (with electrical continuity throughout) from the MET to to the incoming water pipe at the point of entry, couldn't one?

If you mean purposely laid parallel to the water pipe then, yes.

Yes, that's precisely what I meant. I don't think the regs actually insist that a protective conductor be identified by G/Y markings (or, indeed, even insist that it is insulated at all).

In common sense/safety terms, I suppose what this all comes down to is the question of how likely one feels it is that (given some warning labels) an internal water supply pipe would be interfered with such as to destroy the electrical continuity (and how much more likely one feels that is than a plumber, or whoever, disconnecting or damaging a G/Y bonding conductor).

Kind Regards, John

 

[EFLImpudence]

Sure, and that obviously makes sense. However, as above, if one considers most of the internal pipe to be a bonding conductor then one is bonding the incoming pipe 'at its origin', isn't one? As you go on to say

... If so, then it must be considered to be its own bonding conductor.

This is not allowed for a gas pipe ...

It isn't - presumably because of concerns about potentially high currents being carried by a pipe containing gas. However, if you accept the arguments above, there is presumably no reason why a water pipe could not be used as (most of) the 'bonding conductor' for an incoming gas pipe.

No there is definitely nothing wrong with using a water pipe as the bonding conductor for the gas supply.

This thread is from an OP with difficulty getting a conductor from the MET to point of entry.
How far do you think 'where practicable' allows - with, as usual, no specific definition?

 

[JohnW2]

No there is definitely nothing wrong with using a water pipe as the bonding conductor for the gas supply. ... This thread is from an OP with difficulty getting a conductor from the MET to point of entry.

Indeed, but since you made that suggestion, and asked the OP if there was a nearby water pipe, we haven't heard back from him (he did say that he does not get online very often) - so we have to wait to see if that is an option for him.

How far do you think 'where practicable' allows - with, as usual, no specific definition?

As always, your guess/view is as good as mine. However, I would personally be a bit uncomfortable bonding a gas pipe a considerable distance from where it entered the property, since that would effectively be using the pipe as its own bonding conductor - which, as we know, is specifically forbidden. In most circumstances, as discussed, I would have no similar discomfort if it were a water pipe.

However, are we perhaps not all missing something? AFAICS, no-one seems to have asked the OP what sort of service pipe feeds his meter. The copper gas pipe we're talking about comes from an external meter. If that meter is supplied by plastic pipe (or, indeed, if the meter does not provide electrical continuity), would it not be quite possible that the gas pipe entering the house is not an extraneous-c-p and therefore does not require any main bonding at all?

Kind Regards, John

 

[EFLImpudence]

However, are we perhaps not all missing something? AFAICS, no-one seems to have asked the OP what sort of service pipe feeds his meter. The copper gas pipe we're talking about comes from an external meter. If that meter is supplied by plastic pipe (or, indeed, if the meter does not provide electrical continuity), would it not be quite possible that the gas pipe entering the house is not an extraneous-c-p and therefore does not require any main bonding at all?

Yes, that is true.

He did not say, nor was he asked, what has lead to the situation where he is having to ask about bonding the gas pipe.

Gas safety check perhaps ?

 

[JohnW2]

.... would it not be quite possible that the gas pipe entering the house is not an extraneous-c-p and therefore does not require any main bonding at all?

Yes, that is true. He did not say, nor was he asked, what has lead to the situation where he is having to ask about bonding the gas pipe. Gas safety check perhaps ?

As you imply, there are things we need to know. It's possible that the issue has arisen because someone (as you say, maybe in the context of a gas safety check) has suggested the need for main bonding which, in fact, is not necessary.

Kind Regards, John

 

[Coaster]

Coaster: Is there by chance a water pipe near (or more accessible to) the gas entry point.

It is permitted to use a water pipe as the bonding conductor for the gas pipe (but not vice versa).
So if you could connect the gas pipe to a nearby water pipe and verify its continuity, that would be satisfactory.

nope. thats way out the way.. so looks like the wire routing option unfortunatly

 

[JohnW2]

nope. thats way out the way.. so looks like the wire routing option unfortunatly

Maybe. However, as I've recently written, the most crucial question is the nature (material) of the pipe supplying the gas meter. If it is plastic, and the meter (and all of your copper pipe) are above ground, then there probably is no need to bond the gas pipework at all.

Kind Regards, Johyn