Thursday debate BS7671 vs CoMCoP & Gas Safe

I was on FaceBook the other day a saw a meter box which had the gas meter removed.  They had connected an Earth/Bond cable to the 2 ends of the remaining now defunct gas pipes.  It seems this is standard practice when a Gas meter is removed.

Several questions and points to discuss
If there is NO earth clamp on the customer side of gas meter within the permitted length of 600 mm of the outlet union of the meter; and before any branch (tee) in the pipework should the Earth bond be installed by the Gas meter engineer?  The practice of just putting the bond across where the gas meter used to be without proper consideration means that a healthy Ze and Zs could be compromised.  Additionally they could accidentally introduce potential into the building.  Do the Gas meter engineers test to see if this is an Extraneous conductive part?

Scenario 2
There is an Earth Bond of customer side of meter do the Gas meter engineers check with a clamp meter to see if there is mA or Amps.  mA probably being acceptable but Amps not acceptable.  Consider a PEN fault




As always please be polite and respectful in this purely academic debate.




Come on everybody let’s help inspire the future.

Parents
  • If there is NO earth clamp on the customer side of gas meter within the permitted length of 600 mm of the outlet union of the meter; and before any branch (tee) in the pipework should the Earth bond be installed by the Gas meter engineer? 

    Which bond are you talking about? If it's the one across the meter ... that's safe working practice to stop sparks that might otherwise ignite residual gas when removing the meter, so no-brainer for me, I would do it every time if I were a gas engineer! As to whether it's left in place afterwards, I guess there are pro's and con's

    If it's the consumer's main protective bonding, then I think there's a duty for the gas engineer to inform the owner or other responsible person that the bonding is missing, which could still be a  safety problem when the gas meter is removed, so the report should still happen?

    The practice of just putting the bond across where the gas meter used to be without proper consideration means that a healthy Ze and Zs could be compromised.

    I disagree? Ze should be measured with no extraneous-conductive-parts connected.

    There is an Earth Bond of customer side of meter do the Gas meter engineers check with a clamp meter to see if there is mA or Amps.  mA probably being acceptable but Amps not acceptable. 

    I would say this ought to be part of the safe working practices under Electricity at Work Regulations - mA can kill, so knowledge of what's going on is important for safety regardless.

Reply
  • If there is NO earth clamp on the customer side of gas meter within the permitted length of 600 mm of the outlet union of the meter; and before any branch (tee) in the pipework should the Earth bond be installed by the Gas meter engineer? 

    Which bond are you talking about? If it's the one across the meter ... that's safe working practice to stop sparks that might otherwise ignite residual gas when removing the meter, so no-brainer for me, I would do it every time if I were a gas engineer! As to whether it's left in place afterwards, I guess there are pro's and con's

    If it's the consumer's main protective bonding, then I think there's a duty for the gas engineer to inform the owner or other responsible person that the bonding is missing, which could still be a  safety problem when the gas meter is removed, so the report should still happen?

    The practice of just putting the bond across where the gas meter used to be without proper consideration means that a healthy Ze and Zs could be compromised.

    I disagree? Ze should be measured with no extraneous-conductive-parts connected.

    There is an Earth Bond of customer side of meter do the Gas meter engineers check with a clamp meter to see if there is mA or Amps.  mA probably being acceptable but Amps not acceptable. 

    I would say this ought to be part of the safe working practices under Electricity at Work Regulations - mA can kill, so knowledge of what's going on is important for safety regardless.

Children
  • Hi Graham

    I totally agree using the cross bond for gas meter swap outs but in the post I saw they had removed the gas meter then capped off the supply and left the cross bond in place.  I will try and find the original facebook post showing the picture.