Gas bonding regulations

[AlanE]

There was a thread not so long ago (timewise but I think that thread ran to several pages with the same conclusion).

Just to throw another question, or two, into the same pot; are you saying it is not legally required. If that is the case may I ask on what basis? Please not just according to personal thoughts.

If you was asked to fir an earth connection would you advise customer they were wasting their money as you considered it unnecessary in their particular circumstances?

 

[JohnW2]

Just to throw another question, or two, into the same pot; are you saying it is not legally required. If that is the case may I ask on what basis? Please not just according to personal thoughts.

The regulations are very clear. Anything entering a property which constitutes an "extraneous-conductive-part" must have main bonding. Nothing which is not an "extraneous-conductive-part" is required to be main bonded and, as I recently wrote, to unnecessarily connect something to earth (which is one of the effects of bonding) can actually introduce an unnecessary danger.

In practice, an "extraneous-conductive-part" (in domestic situations, nearly always a water, gas or oil supply pipe) is a metal pipe which enters the property and which has an electrical path to 'true earth' - which essentially means that it travels at least some distance underground.

If you was asked to fir an earth connection would you advise customer they were wasting their money as you considered it unnecessary in their particular circumstances?

If an electrician believes that work they have been asked to do is unnecessary, then they really should point that out to the customer. Furthermore, as above, there is even an argument that to unnecessarily connect something to earth (which bonding will do) actually creates an unnecessary danger.

There is a potential complication (which I don't think we've ever got to the bottom of in discussions) that there is a suggestion that Gas regulations may require bonding even when it is electrically unnecessary, not required by electrical regulations and could even introduce an unnecessary danger. If that is true, I think it has to be people other than us who would have to resolve the conflict between two sets of regulations!

Kind Regards, John

 

[EFLImpudence]

Just to throw another question, or two, into the same pot; are you saying it is not legally required. If that is the case may I ask on what basis?

Firstly, there is nothing "legal" about it - the electrical regulations are not statutory - apart from Part P of the Building Regulations which states that, in domestic premises, all electrical work must be carried out to ensure safety.

Please not just according to personal thoughts.

No, just facts.

Earthing is not a good thing in its own right. It is a necessary evil for metal appliances and accessories so that, should they become live because of a fault, the protective device will open and disconnect the supply.
These metal items, are all connected together by their respective Circuit Protective Conductors (earth wires). Consequently, when one becomes live, because of a fault, they all do, for the short time until disconnection.
Any pipes connected to these same CPCs also become live during this short time.
Therefore any pipes NOT connected to these CPCs should NOT be connected to them by unnecessary Bonding (which isn't bonding, but unnecessary earthing).

Bonding is only required for parts because they are already 'earthed' by some means - either the electrical installation or the ground.
Parts which have absolutely NO connection to any 'earth' of any kind must NOT be bonded or earthed - except, of course, the unfortunate metal bits of electrical equipment.

Bonding equalises the potential between earthed parts during such faults.

If you was asked to fir an earth connection would you advise customer they were wasting their money as you considered it unnecessary in their particular circumstances?

If you are talking about Main Bonding, as we have been, then it is NOT 'earthing'.
It is installed to equalise the true earth potential - where a pipe (an extraneous-conductive-part) is connected to the ground - and the installation earthing at the Main Earthing Terminal.

If any pipes entering the premises are not in contact with the ground (not e-c-ps) then they have no potential (different or otherwise) to equalise and are better left that way.
Actually most of thes pipes will be connected to the CPCs of boilers, immersions etc. (as above) so unnecessary bonding does not really matter - although it will do no good - but they might NOT be by virtue of plastic pipe inserts etc.

 

[AlanE]

Interesting, as gasmen (well I was until I retired almost 10 years ago) we are required if no 'earth*' connection is visible within 600mm of the meter we are required to notify 'the responsible person' normally the house owner, or landlord in case of gas safety check, in writing of the need to contact an electrician, since we would not normally be qualified to carry out electrical work (and subsequent testing required).

I agree with differences between electrical regs which is not a legal document wheras gas regs are. It is a pity all cannot agree (I mean those who write these things up to start with) to what is or is not required and then be consistant.

*I have used the simple term 'earth' to cover all different types of earthing/bonding including terminology changes etc.

 

[EFLImpudence]

Interesting, as gasmen (well I was until I retired almost 10 years ago) we are required if no 'earth*' connection is visible within 600mm of the meter we are required to notify 'the responsible person' normally the house owner, or landlord in case of gas safety check, in writing of the need to contact an electrician, since we would not normally be qualified to carry out electrical work (and subsequent testing required).

That's fair enough.

The 600mm. only ever applied to indoor meters.
That regulation was and always has been electrically wrong. It has now at last been corrected.

I agree with differences between electrical regs which is not a legal document wheras gas regs are. It is a pity all cannot agree (I mean those who write these things up to start with) to what is or is not required and then be consistant.

I don't know to what you refer specifically but there isn't much that is 'up for debate'. A lot of electricians do not understand bonding either.

*I have used the simple term 'earth' to cover all different types of earthing/bonding including terminology changes etc.

You shouldn't really.
Earthing is to cause disconnection in the event of a fault.
Bonding is to equalise potential (voltage) during that fault.

 

[JohnW2]

Interesting, as gasmen (well I was until I retired almost 10 years ago) we are required if no 'earth*' connection is visible within 600mm of the meter we are required to notify 'the responsible person' normally the house owner, or landlord in case of gas safety check, in writing of the need to contact an electrician, since we would not normally be qualified to carry out electrical work (and subsequent testing required).

I think that some of it is to do with history. As I need not tell you, once upon a time, all gas supply pipes were metal, as were the meters - so there was always going to be an electrical need for bonding of the gas pipework. As plastic supply pipes and external meters became more common, the electrical need/requirement for bonding became less common.

I agree with differences between electrical regs which is not a legal document wheras gas regs are. It is a pity all cannot agree (I mean those who write these things up to start with) to what is or is not required and then be consistant.

I suspect one issue is that those interested in electrical safety and gas safety have different agendas, which may well conflict - in which case some referee really needs to decide which is the lesser of the evils.

One thing that somewhat surprises/confuses me is that the gas regulations don't actually 'oppose' (or 'forbid') bonding of gas supply pipes (when it is needed electrically). It is an inevitable electrical consequence of bonding a gas pipe (that needs bonding) that, under certain fault conditions, very high currents could flow in the gas pipes. Particularly if there are any ('electrically') 'iffy' joints in the gas pipe, that could lead to considerable local heating or even sparks, neither of which I would think would be welcomed in a gas pipe!

Kind Regards, John
Edit: messed up formatting mended

 

[ban-all-sheds]

I don't seam to be able to edit old posts.

It's a stitch up.

 

[ban-all-sheds]

Interesting, as gasmen (well I was until I retired almost 10 years ago) we are required if no 'earth*' connection is visible within 600mm of the meter we are required to notify 'the responsible person' normally the house owner, or landlord in case of gas safety check, in writing of the need to contact an electrician, since we would not normally be qualified to carry out electrical work (and subsequent testing required).

I think that if I were a landlord, and therefore not really in a position to ignore such written notification, I'd be mightily peeved if that kept happening, and my electrician kept saying "It's not necessary - the gas guy doesn't understand." Quite possibly peeved enough to refuse to pay for the safety check and to initiate legal action against the person(s) who kept sending people to do a job which they were not capable of doing satisfactorily.

 

[AndyPRK]

It would be easier and cheaper to install a bit if green yellow wire to save arguement.
And that is what happens! From when built new

 

[ban-all-sheds]

Easier and cheaper be *("&$"*%*ed.

People who cannot do their jobs properly need to be kicked until they either can or they give up trying and switch to something they can cope with.

 

[AndyPRK]

It’s not the Gas mans fault or the gas person doing the Gas safe check.
They are just completing a form.

See link above.

 

[ban-all-sheds]

It’s not the Gas mans fault or the gas person doing the Gas safe check.

YES

IT

IS

 

[JohnW2]

It would be easier and cheaper to install a bit if green yellow wire to save arguement. ... And that is what happens!

That's obviously not a very satisfactory approach, even if it is 'what happens'.

As I wrote before, at least with gas pipes it probably 'does no harm' - but what if it were the identical situation but with water pipes. Are you happy about the theoretical danger which is introduced if one unnecessarily connects water pipes to earth?

Kind Regards, John

 

[EFLImpudence]

I do not know what, if anything, the Gas Regulations actually say about it but -

what has the bonding got to do with a Gas Safety Inspection?

It has been commented upon that the electrical regulations - or rather opinions on them - are inconsistent.
I suspected the same is true for the gas industry - cross-bonding under the boiler, anyone?

 

[JohnW2]

I do not know what, if anything, the Gas Regulations actually say about it but - what has the bonding got to do with a Gas Safety Inspection?

Quite. As I recently wrote, I could probably understand the Gas Regulations forbidding bonding (or any other connection to the electrical installation's MET) of their (metal) gas supply pipes (hence effectively requiring 'insulating sections'), because of perceived 'gas dangers' if very high currents flowed through their gas pipes, but it's much harder to see what 'requiring' bonding would have to do with 'gas safety'.

Kind Regards, John