In California we are using the 2001 CEC which is based on the 1999 NEC. 250-104(b) says that the interior metal gas piping must be bonded to the grounding electrode system. It doesn’t say anything about likely to become energized.
For many years every jurisdiction I have worked in except San Jose has required a bonding jumper between the hot, cold and gas pipes at the water heater. If you tell the inspector that the NEC permits the EGC of the appliances likely to energize the piping to serve as the bonding jumper he or she will tell you they still want the jumper at the heater. I have spent too much time arguing with inspectors over this issue and have decided to install the jumper for them. Now that we are on the 99 NEC I don’t have much of an argument but since I haven’t run across any inspectors that will not permit this jumper to be at the water heater I keep my mouth shut. Mark has finally run across some inspectors that realized what the 99 NEC requires.
Curt
