2014 NEC 250.104(B) Bonding (Gas piping)

[CuriousHomeInspector]

2014 NEC 250.104(B)(5) lists "one or more grounding electrodes used" as an appropriate bonding locationfor "other metal piping" such as gas distribution piping.

I often see a ground rod or rods driven near the gas piping entrance to the house, and a bonding clamp etc connecting the pipe to the ground rod, but nothing going back to the service ground.

My question is if you use a ground rod at the metal gas pipe entrance to the structure, is there also a requirement for that separate ground rod to also be bonded to the service grounding conductor? If so, then why would we even have this option if we're going to have to run the conductor all the way back to the service ground anyway?

Thank you

 

[Dennis Alwon]

There may be a few reasons but obviously, the installer is not familiar with what the code requires. If a ground rod is installed it must be tied back to the service and hopefully, the installer did not bond the gas pipe on the line side of the meter.

Bonding the gas pipe back to the service is required when CSST piping is used, however if the piping is black iron then the equipment grounding conductor for the circuit that feeds any gas appliances will count as the bonding requirement. 250.104(B)