This can get to be interesting, as the other AHJ - the gas utility - tends to get nervous when you start attaching wires to the gas pipes.
I understate the case ... here the GasCo quite bluntly says gas lines are NOT to be grounded. There's a mighty fine distinction between 'grounding' and 'bonding.'
In any event, since we are talking about the returning of static electricity to Mother Earth, we ARE discussing grounding, and not bonding. Mitigating lightning damage (grounding) has nothing to do with clearing faults (bonding).
Since the grounding electrode system is always carrying some current, I can understand why the GasCo gets touchy about sparks flying when the open a gas fitting. Unlike the plumbing, you're not likely to find insulating unions on a gas line.
