Hi All,

With the advent of Plastic incoming services and plastic internal services the need for main earth bonding of the Gas meter has become redundant under the BS7671.

However most internal gas piping is either copper or flexible steel with plastic sheath.

The question I'm going to ask is how does the gas meter work, does it have moving parts and does it have continuity across the meter?

The reason for asking this question is because we are not bonding this meter, could there eventually be a build-up of static energy that can't be dissipated or when it does dissipate creates a spark.

I don't know a lot about Gas, but I do know it contains a percentage of water and other minerals, I also do know that to create and explosion you need three elements, which one should not be present in the gas meter (air).

However in practice because of leak's and water there is that possibility of a percentage of air been present, so the three element can be present at a gas meter.

In my case - external incoming services are plastic (water/Gas), the waterpipe is copper to the boiler, boiler pipework is plastic and the internal gas pipe to boiler is a flexible steel with plastic sheath pipe, which we are going to test to see if we have continuity between the gas boiler and the gas meter. If there is continuity from the boiler to the gas meter then it's a simple matter of cross bonding at the boiler with a suitable label and a note on the test certificates will suffice.

(As a additional note the Electrical Contractor has refused to undertake the earth test and to cross bond stating that because the incoming services are plastic they don't need to earth/cross-bond the installation!)

Can someone from the BS7671 team please review this, as I think we might need to earth gas meters, especially moving forward with smart meters etc.

If I've posted this wrongly, please advise as it's the first time posting something for a long time. 

Regards John