Grounding of Gas Piping

[mccuen352]

All over the State of South Carolina Electrical Inspectors are requiring us to Ground the Gas where it enters a home to the Ground Electrode System but the NEC 250.52 (8) (B) specifically states not to do that! Its says "Not Permitted for Use as Grounding Electrodes" (1) "Metal Underground gas piping systems". Am I misinterpreting the Code on this? I am really concerned about potential risks to the Homeowner as well as us, if anyone can please clarify this for me once and for all.

 

[Fred B]

Bonding requirements and Grounding requirements are not the same thing. Gas Pipe cannot be used as a Grounding Electrode, but it must be Bonded to the GES or to the circuit(s) that code wording "Likely to become energized" from. This terminology is very loosely interpreted and generally the metal gas line is universally just bonded, "just in case".

So hopefully the gas line is not being used as a Grounding Electrode, but simply being bonded.

 

[Earthed]

HDPE (high density polyethylene) tubing would not act as an electrode. Also, do not connect the tracer wire to the GES.

 

[infinity]

The NEC is clear, the gas pipe is bonded by the EGC in the circuit feeding the gas appliance. That's all that is required. CSST may have a separate requirement but that is not part of the electrical code unless adopted by a local amendment.

 

[augie47]

Natural gas systems normally employ some type of dielectric connector (usually a part of the gas meter) that isolates the underground piping from the premises piping so when you bond the interior piping you are not actually connecting to the underground piping.
If the inspectors are requiring it my guess would be there is CSST piping involved and what you describe is required by the mechanical codes.

 

[ptonsparky]

You are Bonding the gas meter, you are not using it and the piping as a Grounding Electrode. Its use as a GE is not allowed, so remove that thought from your head.