"John Grabowski" writes:
The correct term is "Bonded". The current code as written requires that all
interior metal piping be bonded together. This can be accomplished by using
#6 copper wire and approved clamps. It is common in New Jersey to bond the
hot and cold water pipes together at the water heater location. It would be
very easy to continue the bonding wire to the gas pipe at the water heater.
Some jurisdictions do not require that the gas pipe also be bonded. Some
gas companies do not want their pipes bonded. The electrical inspector would
have noticed this and would have failed the job if it wasn't done correctly.

Did the electrician also install at least one (Preferably two) ground rod?

Do you need to explicitly bond the hot and cold pipes together using a
copper wire jumper, or is there electrical continuity through the war
heater? (Note my house is all coper pipes)

Also can I bond the gas pipe to the subpanel indirectly by just
jumpering the gas water heater intake pipe to the cold water pipe
entering the hot water heater?

Or is it required to directly bond the gas intake pipe at the meter to
the panel ground using a single wire?

Or is all of this unnecessary since the water heater itself provides a
conducting path bonding the gas pipe system to the water pipe system
(and then back through the water pipe to the panel ground)