"EXT" writes:

While both pipes are buried and may be made of metal, only the water line
should be used as a ground unless it is fed by a plastic pipe. The gas line
should NEVER be used as a ground, although it should be grounded to the
building ground, because gas supply lines can also be made of plastic, and
even if it is metallic it will have an insulating fitting at the meter to
prevent interference with cathodic corrosion protection of the underground
lines.

If you have a furnace or a powered water heater and grounded wiring, the
connection through this equipment will also ground the gas lines. However, I
believe NEC requires a separate cross connection to ensure proper grounding.


Yes, but my question remains whether to attach the gas pipe to panel
ground not for the purpose of grounding the panel but for the converse
purpose of ensuring that the metal pipe inside the house never gets energized.