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Posted By: golf junkie Gas Pipe Bonding?? - 08/01/01 12:41 AM
This is a continuation of the discussion in the "Grounding to water pipes" thread.

My take on gas pipe bonding is;

It's required by the NEC.

The AHJ doesn't enforce it.

If the gas company finds it, they will disconnect it.

As a result of the above, we don't install a bonding jumper to the gas pipe.

?????????????

GJ
Posted By: Anonymous Re: Gas Pipe Bonding?? - 08/01/01 01:06 AM
My take on gas pipe bonding is:

It's required by the NEC.
I do it. If I don't do it, fault current will run through the gas line anyway, but instead via a hazardous circuit.
If necessary, I'll put it where the the gas company won't easily find it. If they do disconnect it, it's their liability. If I don't install it, its my liability.

As a result of the above, I install a bonding jumper to the steel gas pipe (premises side, of course).
Posted By: Redsy Re: Gas Pipe Bonding?? - 08/01/01 01:37 AM
Our local utility (PECO) requires and expects to see it. Besides, isn't it likely that incidental contact will occur between the gas line and an appliance that is in contact with ground, anyway. Removing the bond doesn't seem to fully isolate the gas line.

[This message has been edited by Redsy (edited 07-31-2001).]
Posted By: Tom Re: Gas Pipe Bonding?? - 08/01/01 09:34 PM
As Redsy pointed out, any appliance that uses gas & electric will likely make a bonding connection.

The gas companies don't follow their own code, which is where the requirement is derived from.

There were several proposals made about 250-104(b), but I haven't had time to read them.
Posted By: bordew Re: Gas Pipe Bonding?? - 09/02/01 03:13 PM
Quote
Originally posted by Dspark:
My take on gas pipe bonding is:

It's required by the NEC.
I do it. If I don't do it, fault current will run through the gas line anyway, but instead via a hazardous circuit.
If necessary, I'll put it where the the gas company won't easily find it. If they do disconnect it, it's their liability. If I don't install it, its my liability.

As a result of the above, I install a bonding jumper to the steel gas pipe (premises side, of course).

DSPARk;
I agree with everything you said, although I never heard of the gas company disconnecting them.
When it first came out in '99 the first service upgrade I did, I bonded the gas line as required in the code. the inspector promptly called me and asked me," why did You bond the gas line" and replied well thats what the code says to do, he said we are not going to do that in our area.
In October '99 I went to my state required code classes for 10 hours CEUs, and the inspector there said you must bbond to the gas line, so go figure.
Posted By: sparky Re: Gas Pipe Bonding?? - 09/02/01 03:32 PM
I beleive there is a long & colorful history of gas pipe vs. ECG, GEC, and bonding that is again going to change in 2002.... [Linked Image]
Posted By: Anonymous Re: Gas Pipe Bonding?? - 09/04/01 08:26 PM
>going to change in 2002....

I called someone down on this claim and no supporting documentation was forthcoming except some ROPs that failed to pass.

Do you have a verifiable reason to believe that it is changing?




[This message has been edited by Dspark (edited 09-04-2001).]
Posted By: George Corron Re: Gas Pipe Bonding?? - 09/04/01 10:45 PM
FYI guys. The code says you cannot use the gas pipe as an electrode, and you WILL bond it to the system. The bond can come from the piece of equipment likely to energize (all of which used to be in 250-80-(b) before they messed up 250).

A local jurisdiction in Va was requiring a separate ground rod to the gas UNCONNECTED to the service GEC, in other words isolated.

I won that fight about 5 years ago as far as VA is concerned. So in VA, you will bond it as per NEC, but you cannot use it as an electrode the way we used to.
Posted By: pauluk Re: Gas Pipe Bonding?? - 09/04/01 10:51 PM
For what it's worth, the British Regs. say that gas lines should be bonded, but are not allowed to be used as a substitute for a ground rod or as a grounding connection.
Posted By: Anonymous Re: Gas Pipe Bonding?? - 09/05/01 12:10 AM
Neither the gas line nor water line should be used in place of the necessary dedicated grounding electrode(s).
Posted By: sparky Re: Gas Pipe Bonding?? - 09/05/01 12:14 AM
Do you have a verifiable reason to believe that it is changing?

only in it's history, and the now defunct ROP's.

So....can we install a UFER and use the G-rods to rabbit hunt instead?
[Linked Image]
Posted By: Anonymous Re: Gas Pipe Bonding?? - 09/05/01 12:21 AM
I challenged a cocky teenager to show me how far he could throw a ground rod. He had not picked it up and didn't realize how heavy it was. Mr. Ufer is a winner. But if you hunt with a 0.625" ground rod, I'll bet on the rabbits. Sorry!
Posted By: dlabrenz Re: Gas Pipe Bonding?? - 09/05/01 02:36 AM
this appears to be the languge that was proposed for the 2002 NEC.

Looks like we are reverting to the language that was in the previous code.

Revise Section 250.104(B) of the 2002 NEC ROP draft to read as
follows:
(B) Other Metal Piping. Where installed in or attached to a
building or structure, metal piping system(s), including gas piping,
that may become energized shall be bonded to the service
equipment enclosure, the grounded conductor at the service, the
grounding electrode conductor where of sufficient size, or to the
one or more grounding electrodes used. The bonding jumper(s)
shall be sized in accordance with 250.122 using the rating of the
circuit that may energize the piping system(s). The equipment
grounding conductor for the circuit that may energize the piping
shall be permitted to serve as the bonding means. The points of
attachment of the bonding jumper(s) shall be accessible.
FPN: Bonding all piping and metal air ducts within the premises
will provide additional safety.
Posted By: Anonymous Re: Gas Pipe Bonding?? - 09/05/01 02:51 AM
Was that language final?
Posted By: sparky Re: Gas Pipe Bonding?? - 09/05/01 10:33 AM
Dspark,
I'm just pointing out Ufer's superior ohmic value vs. G-rods. the entire history of GEC's is somewhat checkered, even the UG water pipe has been opposed since day one by water workers orginizations.

the problem is in the lack of 250 to allow the field sparky to quantify GEC values.

what say we use 250-52(b) for an underground fuel tank?? [Linked Image]
Posted By: Anonymous Re: Gas Pipe Bonding?? - 09/06/01 12:41 AM
I just don't see the problem that you do. The Ufer is superior primarily because of its great earth contact area.

To me it appears
that those who oppose
have an open circuit between the ears.

Water mains must be bonded.
Workers must treat them as energized and jumper around them before removing or replacing a meter, valve, fitting, or section.

If there is a problem, it has to be insufficient bonding. They should be demanding using dielectric couplings where necessary. Not bonding is not a real solution.
Posted By: WARREN1 Re: Gas Pipe Bonding?? - 09/06/01 05:07 PM
There are some municipalities that will not allow you to bond to the water systems, because of the possibility of low leakage currents eating away their old piping systems. I once worked on a project in Charleston, SC and at that time the local code would not allow bonding to their water pipes, and yes, we had to isolate project piping from their system. If gas and water companies used cathodic protection schemes on their systems, there might not be a problem. However, that will be very expensive and cost prohibitive to gas and water companies and would reflect in higher rates, which we don't want.
Posted By: Anonymous Re: Gas Pipe Bonding?? - 09/06/01 08:59 PM
Putting in a dielectric union or coupling underground outside the building solves the problem, does it not?
Posted By: sparky Re: Gas Pipe Bonding?? - 09/06/01 10:14 PM
well yes, it solves the problem of the water workers doing a nuetral impression, yet diminishes the value of the Grounding Electrode (note it's the only full sized one, can't cop out to a #6..)

it would also solve the problem of mettallic raceways common to the serving X-former.

would'nt you can the entire deal for a UFER ?
Posted By: Anonymous Re: Gas Pipe Bonding?? - 09/06/01 10:58 PM
>diminishes the value of the Grounding Electrode
As if I am supposed to care? I could say the same thing if they wanted to make the whole line plastic. If someone wants a good GE, he needs to make it.

>it would also solve the problem of metallic raceways common to the serving X-former.
Right.

>wouldn't you can the entire deal for an Ufer?
No. The metallic interior piping must be bonded. I don't accept any exception.

Ufer grounds are not exactly retrofit items, certainly not in most cases.
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