Am I using gas pipe as electrode

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I tried to reply to this 4 hours ago, but lost the thread because I accidentally hit the Back button which redoes the New search instead of just going back to the previously generated list like it it's supposed to. I didn't know what subforum it was in, so I gave up. Now I got lucky to see the picture on the main page and recognized it as the thread I was looking for.

So, anyway, my idea is that NO, the sketch doesn't necessarily mean the gas pipe is an electrode, just that it's also purposely bonded to the grounding system, which also includes the Ufer, water pipe, and building steel. The gas pipe is likely also bonded through contact at many places with building steel anyway.
 
The code states you cannot use gas pipe as an electrode but that doesn't mean you cannot bond it. Most gas meters have a di-electric fitting which isolates the pipe in the building from the underground piping.

So my answer is that I cannot tell if you are using the pipe as an electrode. No if there is a meter in the line and yes if the pipe goes directly into the earth for 10' or more
 
What i understand in 250.50, the underground gas pipes/tanks are prohibited from being GEC, the OP doesn't mention the underground installation, also pipes inside building don't necessarily have a conductivity with underground services.

Am i missing something here ?
 
m sleem said:
What i understand in 250.50, the underground gas pipes/tanks are prohibited from being GEC, the OP doesn't mention the underground installation, also pipes inside building don't necessarily have a conductivity with underground services.

Am i missing something here ?
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I don't think so.

You are not allowed to use them as grounding electrodes, 250.52(B). Do not run a GEC to the utility side of the gas meter. That may be just outside the building or, until recently at my shop, 100' away.


ECs must bond the interior lines per 250.104(B) and table 250.122 which typically would require no larger than a #12. You as an EE can tell us to bond the interior gas lines via any of 250.104(B)(1) thru (5) if that is your desire.

In the case of my shop and the 100' of buried black metal gas line, did that make it a Grounding Electrode or just bonded when I tapped the GEC as it went to the two rods that serve as my GEC?
 
Natural gas, utility almost always has an isolation union or other fitting usually at the meter, they don't want any stray currents on their underground piping.

Most newer installations have a non metallic piping underground anyway and transition to metallic at the riser mostly only for physical abuse resistance reasons.

LP gas you still see copper tubing used underground and no isolating fittings, but these usually are smaller localized systems as well.
 
Fortunately you are allowed/required to bond the gas pipe whether or not there is a dielectric union, and that is not considered as using it as a ground electrode.

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GoldDigger said:
Fortunately you are allowed/required to bond the gas pipe whether or not there is a dielectric union, and that is not considered as using it as a ground electrode.

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And the EGC for whatever may energize the piping is all that is needed to make that bond.

CSST may have it's own additional rules that are outside the requirements of NEC.
 
kwired said:
And the EGC for whatever may energize the piping is all that is needed to make that bond.

CSST may have it's own additional rules that are outside the requirements of NEC.
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The appliance EGC assures that the piping on the "load side" of the CSST is grounded. The reason for bonding a gas piping system is to make sure that the piping on the "line side" of the CSST is equally grounded, so the CSST is never subject to having to carry a fault current.
 
In my area the new gas services are HPDE. Before that they were PVC coated iron pipe. I got a couple of sections for a closet rod, strong, quiet, and slick.
And the gas company has cathodic protection on the gas mains, seems like if you bond to it, they know and will find you.
 
LarryFine said:
The appliance EGC assures that the piping on the "load side" of the CSST is grounded. The reason for bonding a gas piping system is to make sure that the piping on the "line side" of the CSST is equally grounded, so the CSST is never subject to having to carry a fault current.
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One clarification: the fault current which causes pinhole damage to CSST is lightning induced current, not line fault current. Lightning induced (not necessarily direct strike) current has high frequency components and orders of magnitude greater current compared to line faults.

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