Is underground gas pipe used as GE

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hhsting

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Attached sketch shows main service disconnect with grounding electrode conductor to external bus. The external bus has bonding jumper to steel, bonding jumper to water pipe, bonding jumper to underground metallic gas pipe and other metal pipe.


Is the underground metallic gas pipe used as grounding electrode?
477bab76f02458f6fcb26bdeb36874ca.jpg
 
ptonsparky said:
Typically, No.
Who wrote the specs?
Click to expand...

Why not? Its part of main service grounding electrode system. NEC 2014 section 250.64(F)(3) says from busbar bonding jumper to electrodes so whatever bonding jumper you have from busbar goes to grounding electrode.
 
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I wonder if there is confusion between internal and external piping. Perhaps they are bonding and grounding from the same point? Are interior pipes metal? Are exterior pipes metal? Interior gas pipes are usually bonded, but the exterior gas pipe cannot be used as a GEC, so the pipe bonding clamp needs to be on the correct side of the meter.
 
Code does not allow GE connection on GACO (gas company) side of meter, as pointed out. GACO doesn't want the connect as it affects their cathodic protection and gas service lines (in my area) are HDPE.
And if the GE connection is made on the customer side of the meter, there is an insulating union on the meter, so in any event you won't be able to use the gas line as a GE.
 
Your sketch shows and external Grounding Buss and a GEC to the gas line. It does not indicate it goes to the underground gas line,.
It is not unusual to connect to the gas piping OUTSIDE at the meter as long as you do not connect to the incoming underground pipe.
 
250.104(B)* requires gas piping internal to the building to be bonded and allows it to be bonded to the grounding electrode conductor among other options. The sketch is vauge as to whether it refers to internal gas piping or utility side gas pipe, although the "other metal piping" language suggests it is about meeting this requirement.

In other words, if the gas piping is internal to the building the sketch is not only not a violation but it shows a means of meeting an NEC requirement.

*2020 NEC reference. Numbering changed from previous cycle.
 
Actually NEC 2014 Section 250.104(B) says the following:


If installed in, or attached to, a building or structure, a metal piping system(s), including gas piping, that is likely to become energized shall be bonded to any of the following:

(1) Equipment grounding conductor for the circuit that is likely to energize the piping system

(2) Service equipment enclosure

(3) Grounded conductor at the service

(4) Grounding electrode conductor, if of sufficient size

(5) One or more grounding electrodes used


It says you can bond to grounding electrode conductor or one or more grounding electrode

In the sketch it bond from ground bus to the gas pipe and other metal pipe. However above code section their is no mention of ground bus bar to gas pipe. Is the sketch even in compliance with NEC 2014 section 250.104(B)?
 
hhsting said:
Yes I know but in the sketch is it in violation of 250.52(B)(1)?
Click to expand...
As mentioned sketch is vague and your description refers to the connection as a connections to the grounding electrode(s). Now if the sketch reference to "external ground bus" is simply a bonding bridge, and the connected items are simply being bonded to the grounding electrode(s) then it is compliant as long as the bonding of gas line is as already stated not on utility side of meter. But if your statement regarding the intention of sketch as making grounding electrode(s) is accurate, then it is in violation.
You need to decide are you making the grounding electrode or a bonding bridge.
Absent of any notation in sketch of separate grounding electrode(s) it would appear you are making "them" with the various metal parts including the gas pipe and as drawn it would be a violation of 250.52(B)(1)
 
Read 250.62(E) and you will see what you have scribbled is likely compliant if the common bar meets the requirements of 250.62(E) and, as mentioned multiple times, the connection is to the gas pipe on the downstream side of the gas meter !

Make tha 250.64(F)(3) in the '14 Code
 
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