Main Bonding

[Dave301]

House has had gas installed. Meter is outside of property at front. The box is not attached to the building and the gas pipe enters the property under the floorboards. The pipework goes to the boiler at the rear of the property under the floor the whole way. Is it OK to put a bonding clamp outside of the property on the only accessible portion of pipe? Open to the elements?

 

[HandySparks]

I'd say yes. But, personally, I'd try and put it on the gas pipe where it emerges from the floor on its way up to the boiler.

 

[7029 dave]

Why not.?

 

[Dave301]

Well I'm thinking long term it's going to get rather corroded. The only problem with where it emerges is its not even close to 600mm from the meter. More like 10m.

 

[7029 dave]

Well I'm thinking long term it's going to get rather corroded. The only problem with where it emerges is its not even close to 600m from the meter. More like 10m.

As close as practical, if that is the nearest only accessible point then I would make my term there.

 

[HandySparks]

Well I'm thinking long term it's going to get rather corroded. The only problem with where it emerges is its not even close to 600mm from the meter. More like 10m.

The regs don't specify the location of main bonds.

The OSG says: All main bonding connections are to be applied to the consumer's side of any meter, main stop valve or insulating insert and, where practicable, within 600mm of the meter outlet union or point of entry to the building if the meter is external.

My suggested location complies with the recommendation in the OSG. (I regard the length of pipe under the floor as normally inaccessible, so the point of entry is where if comes through the floor.)

 

[HandySparks]

The regs don't specify the location of main bonds.

The OSG says: All main bonding connections are to be applied to the consumer's side of any meter, main stop valve or insulating insert and, where practicable, within 600mm of the meter outlet union or point of entry to the building if the meter is external.

My suggested location complies with the recommendation in the OSG. (I regard the length of pipe under the floor as normally inaccessible, so the point of entry is where if comes through the floor.)

My mistake, the stuff in the OSG pretty much repeats 544.1.2 in the regs.

 

[Dave301]

OK thanks very much for your help

 

[Silly Sausage]

Along with Handy, the whole point of the bonding is to nullify any external potential.
So you may as well make the connection at a position that is clearly obvious and accessible for I&T.
As Tony pointed out once, the conductivity of a 15 mill copper pipe far exceeds a 10 mill cable.

 

[bigspark17]

Where is the MET situated back or front of house? This is going to be a big factor with ease of cable run i would have thought.

 

[Dave301]

MET is at rear of property near the boiler. So in hindsight a silly question. I think I will bond the first accessible point within the house.
Although it is practicable to do within 600mm of Meter.....

 

[bigspark17]

Preferably within 600mm of meter, if accessibility allowys why not bond it in the gas meter box, then that will combat the corrosion issue.