[TowerTalk] Single Point Service Ground Question

[Jim Miller]

Everything in my house is tied to the single point service entrance as it 
enters the house.

The ground rod is actually inside the house sticking out of the basement 
slab directly under the breaker boxes. Cable (after some nagging), 
telephone, ham antenna feed and of course the grounds for the two fuse boxes 
all tie there.

It occurred to me that I had never seen such a tie for my propane service 
however. I just checked outside and the tank, which is 50ft away from the 
service entrance, has no connection to this single point ground.

The 1000 gallon tank is buried and the service line comes up at the back 
corner of the house, enters a regulator which is mounted on the entrance 
pipe which penetrates the foundation. From there it travels across the 
basement to the furnace. Ground rise potential differences between the tank 
and the service point ground must therefore transit the basement first on 
the metallic flexible gas line, then via the furnace electrical circuit back 
to the box.

I think the National Electrical Code covers all the issues related to 
grounding. Does it say anything about the grounding of the propane service?

tnx
jim ab3cv