Is this requirement being enforced by any AHJ's?
Is this requirement being enforced by any AHJ's? 250.104(B) Other Metal Piping.
Where installed in or attached to a building or structure, metal piping system(s), including gas piping, that may become energized shall be bonded to the service equipment enclosure, the grounded conductor at the service, the grounding electrode conductor where of sufficient size, or to the one or more grounding electrodes used.
The bonding jumper(s) shall be sized in accordance with 250.122 using the rating of the circuit that may energize the piping system(s).
The equipment grounding conductor for the circuit that may energize the piping shall be permitted to serve as the bonding means.
The points of attachment of the bonding jumper(s) shall be accessible.
FPN:Bonding all piping and metal air ducts within the premises will provide additional safety.
Section 250.104(B) was revised for the 2002 Code to state that gas piping is treated exactly the same as all "other metal piping" systems within a building.
NFPA 54 - 6.13 Electrical Bonding and Grounding.
6.13.1 Each aboveground portion of a gas piping system that is likely to become energized shall be electrically continuous and bonded to an effective ground-fault current path.
"Gas piping shall be considered to be bonded when it is connected to gas utilization equipment that is connected to the equipment grounding conductor of the circuit supplying that equipment."
6.13.2 Gas piping shall not be used as a grounding conductor or electrode.
