main equipotential bonding to gas

[aldm]

Hello all, I'm having my gas meter moved from the inside of the house to the outside.

The current meter is aprox 5ft from floor level on the kitchen wall. The earth bond cable runs from floor level up to the meter and is clamped within 600mm on the consumer side of the meter.

The new meter will be on the outside wall and a new gas pipe will run from the meter back into the kitchen and connect back up to the existing services.

When I come to reattach the earth bond, am I right in thinking I can attach to the gas pipe INSIDE the kitchen, i.e point of entry to the building. As this is within the equipotential zone.

I understood the "within 600mm of the meter" rule to only apply if the meter is inside the building. But have read different opinion as to whether point of entry to be inside or outside the building.

 

[PrenticeBoyofDerry]

You can connect the main earth bonding to the gas pipe where it enters the building, ideally within 600mm of entering the property and before any branch pipes. You could if wished to, clamp to customer side within the gas meter cabinet.
The clamp requires to be accessible for inspection, test and maintenance.

 

[bernardgreen]

Some are bonded outside, some are bonded inside directly the pipe comes through the wall.

There is a paradox if the gas pipe is bonded outside and one is being pedantic over the wording of the regs.

Every conductive item that comes into the house has to be bonded to prevent it bringing an extraneous potential into the equipotential area inside the house.

A bond cable going out through the wall to the gas meter could import an extraneous potential and so should itself be bonded with a bond cable from the MET. ( end of pedantic rambling )

 

[JohnW2]

You can connect the main earth bonding to the gas pipe where it enters the building, ideally within 600mm of entering the property and before any branch pipes.

Indeed.

You could if wished to, clamp to customer side within the gas meter cabinet.

I'm inclined to sympathise with Bernard's self-proclaimed 'pedanticism' here and wonder if it is actually strictly compliant with the regs to connect main bonding to the pipe outside of the building but not also inside the building. As Bernard says, there is then an extraneous-conductive-part entering the building which is not bonded within the building. Pedantic, I agree, but ....!! (particularly given that indoor bonding is nearlyalways going to be easier!)

Kind Regards, John

 

[sparkwright]

I seem to recall some gas suppliers have different rules about the bonding to our rules.

Most gas companies expect to see the bonding done outside in the meter box (where the meter is outside at least).

 

[PrenticeBoyofDerry]

There is a paradox if the gas pipe is bonded outside and one is being pedantic over the wording of the regs.

Every conductive item that comes into the house has to be bonded to prevent it bringing an extraneous potential into the equipotential area inside the house.

Would that mean that then mean that the supply line and neutral should be bonded?

 

[RF Lighting]

The regs call for the bond to be within 600mm of the point of entry of the service. It doesn't matter which side of the wall this is on

 

[aldm]

Thanks for the replies, think it will be inside within 600mm of point of entry as this just means I will have to cut back the existing cable and reattach using the original clamp.

 

[aldm]

I seem to recall some gas suppliers have different rules about the bonding to our rules.

Most gas companies expect to see the bonding done outside in the meter box (where the meter is outside at least).

That's what I had heard, hence the question.

It wouldn't be difficult to connect inside the gas box outside, but if there is not enough slack on the original earth bond cable, it would mean I would have to join it (using through lug and not a chocky block ) or run a complete new length and replace the clamp for an external rated one. Not impossible just not as quick and easy if not required.

 

[RF Lighting]

The bond is there for electrical reasons. I couldn't give a stuff if a gas fitter thinks it's wrong.

 

[PrenticeBoyofDerry]

I seem to recall some gas suppliers have different rules about the bonding to our rules.

Most gas companies expect to see the bonding done outside in the meter box (where the meter is outside at least).

I didn't think they cared, they just stick a notice up regardless, if bonded or not, as they generally don't check/don't know how to verify, often leaving the homeowner unsure whether things are safe or not!
I have seen situations where gas meters have had to be moved, the gas board have come in disconnected the main earth bonding and left it dangling, fit new meter and not told the customer that the gas pipe requires bonding, then done one!

 

[JohnW2]

Would that mean that then mean that the supply line and neutral should be bonded?

... I'm afraid that you're not the first person to have suggested/asked that!!

I suppose they do have a fairly sloppy definition of extraneous-conductive-part, since there is no doubt that the L and N supply cables are conductors which are 'liable to introduce a potential' (they do say 'usually', not 'always', earth potential)!!

Kind Regards, John

 

[RF Lighting]

I'm not sure how joe public is going to get his hands on a line or neutral part, so they wouldn't need bonding.

 

[JohnW2]

The regs call for the bond to be within 600mm of the point of entry of the service. It doesn't matter which side of the wall this is on

Yes, the wording of the regs does have that ambiguity, but I wonder if it was actually intentional? Mind you, the reg (544.1.2) does say:

Where practicable the connection shall be made within 600 mm of the meter outlet union or at the point of entry to the building if the meter is external

Although the same ambiguity remains, the wording of that bit I've emboldened strongly suggests to me that they meant/intended 'the point of entry into the inside of the building' - but I accept that no-one can be sure of what they intended.

Kind Regards, John

 

[EFLImpudence]

Hello all, I'm having my gas meter moved from the inside of the house to the outside.

The current meter is aprox 5ft from floor level on the kitchen wall. The earth bond cable runs from floor level up to the meter and is clamped within 600mm on the consumer side of the meter.

The new meter will be on the outside wall and a new gas pipe will run from the meter back into the kitchen and connect back up to the existing services.

When I come to reattach the earth bond, am I right in thinking I can attach to the gas pipe INSIDE the kitchen, i.e point of entry to the building. As this is within the equipotential zone.

I understood the "within 600mm of the meter" rule to only apply if the meter is inside the building. But have read different opinion as to whether point of entry to be inside or outside the building.

You are entirely correct.


The 600mm ONLY applies to meters inside.

It does not apply to the point of entry nor stopcocks.

The only qualification to the point of entry is 'where practicable'.