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gas line pipe grounding


motown1435
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Just wanted to know if grounding of the gas line pipe to the service panel was acceptable. This was house built in 1993 and the service panel was also grounded by way of the copper water line and the meter base had a ground rod. thanks Sm

Not only is it acceptable, it's required. This is called "bonding." The purpose is not to ground the electrical system through the gas pipe, but rather to ensure that the gas pipe can not become energized. In the 1990 NEC, this would have been covered in 250-80(b). Nowadays, it's covered in 250.104.

- Jim Katen, Oregon

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Just wanted to know if grounding of the gas line pipe to the service panel was acceptable. This was house built in 1993 and the service panel was also grounded by way of the copper water line and the meter base had a ground rod. thanks Sm

You're sort of mixing things up. The ground rod is the grounding electrode.

The water line is probably plastic but if it's copper all the way to the main then it can be a grounding electrode as well. The ground rod and the water line provide a path to ground. The gas line is bonded to ground so that it can't become energized.

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Does the bonding always go to the service panel??

It may, and that's what I usually see nowadays. However, you're allowed to use the equipment grounding conductor from the circuit that's likely to energize the piping. In other words, if there's a gas furnace, you can use the green wire from the gas furnace circuit to bond the gas pipe.

- Jim Katen, Oregon

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You're sort of mixing things up. The ground rod is the grounding electrode.

The water line is probably plastic but if it's copper all the way to the main then it can be a grounding electrode as well. The ground rod and the water line provide a path to ground. The gas line is bonded to ground so that it can't become energized.

Why would the main copper line have to go all the way main to be a grounding electrode? I have never heard this before. One of my local AHJs allowed a galvanized water line for an exterior hose faucet to be used as the ground when the main water line was changed to plastic. The quote was, it need to have 5 feet of buried ground contact to act as the grounding electrode. Five feet seemed odd for a distance of ground contact, but to the meter even makes less sense.

Thanks

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Why?

Because he doesn't know what the hell he's talking about.

The NEC prohibits using the plumbing as the sole service grounding electrode. Heck, even an $18 Code Check can explain that to him.

Get Douglas Hansen't book Electrical Inspection of Existing Dwellings - 2001 Edition. Then read it, reread it and then read it again.

ONE TEAM - ONE FIGHT!!!

Mike

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You're sort of mixing things up. The ground rod is the grounding electrode.

The water line is probably plastic but if it's copper all the way to the main then it can be a grounding electrode as well. The ground rod and the water line provide a path to ground. The gas line is bonded to ground so that it can't become energized.

Why would the main copper line have to go all the way main to be a grounding electrode?

It wouldn't. In order for it to be used as a grounding electrode, it needs to have a minimum of 10' in contact with soil. 250.52(A)(1)

I have never heard this before. One of my local AHJs allowed a galvanized water line for an exterior hose faucet to be used as the ground when the main water line was changed to plastic. The quote was, it need to have 5 feet of buried ground contact to act as the grounding electrode. Five feet seemed odd for a distance of ground contact, but to the meter even makes less sense.

I think someone was confused. First, if the main water line was changed to plastic, then it's unlikely that there would be 10' of galvanized piping in contact with soil and you wouldn't be able to use the water pipe as a grounding electrode at all. If there were still 10' of steel pipe in contact with soil, you'd have to connect to it within 5' of the point where it entered the building. (That's where the 5' distance comes in.) 250.52(A)(1)

If there weren't 10' of steel pipe in contact with soil, you'd still have to *bond* the metal water pipes to the grounding electrode system and you could do that anywhere as long as the connection is accessible. 250.104(A)

- Jim Katen, Oregon

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Why?

Because he doesn't know what the hell he's talking about.

The NEC prohibits using the plumbing as the sole service grounding electrode. Heck, even an $18 Code Check can explain that to him.

Uh, Hi Mike,

The water line can be used as a grounding electrode, in fact it may actually be a part of the grounding electrode system described in the original post.

It's my bad on the waterline length. I know it's ten feet, the point I guess I failed to make is that often the line is plastic and then transitions to copper for the trip through the wall.

Sometimes trying to explain theory helps more than a bunch of code cites.

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What if an overhead electric line fell onto your car while you were sitting in it? Would you be afraid?

Same thing with pipes and plumbing. Live electric lines can touch these pipes and send the electricity throughout the entire plumbing system.

There are plenty of stories about people being shocked from their shower, a faucet, and plumbers being shocked while working on the plumbing.

A recent problem with plumbing is that people replace metal pipes with plastic pipes. And only sections, not the entire pipe system. So this may leave portions of metal pipe which are not bonded to ground.

Here they are discussing Washington State and a proposed new rule that plumbers must install bonding wires when replacing sections of metal pipe with plastic...

http://www.terrylove.com/forums/showthr ... e-Plumbers

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As far as the use of the incoming water line for a Grounding Electrode goes -

Article 250.52 in The National Electrical Code ( NEC) Tells us that if Metal Underground Water pie in direct contact with the earth for 10 feet or more IT MUST BE USED.

Article 250.50 Says that if any of these are present they MUST BE USED.

1) - Metal Underground Water Pipe

2) Metal Frame of the Building Steel

3) Concrete Encased Electrode

4) Ground Ring

5) Rod and Pipe Electrodes

6)Other Listed Electrodes

7) Plate Electrodes

Article 250.53 tells us that if the only electrode used is the Underground Water Pipe you MUST ALSO INSTALL ANOTHER ONE.

You are allowed to install any of thoise listed above From #2 to #7.

Most common is to just drive some ground rods to supplement the Under Ground Water Pipe.

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Why?

Because he doesn't know what the hell he's talking about.

The NEC prohibits using the plumbing as the sole service grounding electrode. Heck, even an $18 Code Check can explain that to him.

Uh, Hi Mike,

The water line can be used as a grounding electrode, in fact it may actually be a part of the grounding electrode system described in the original post.

It's my bad on the waterline length. I know it's ten feet, the point I guess I failed to make is that often the line is plastic and then transitions to copper for the trip through the wall.

Sometimes trying to explain theory helps more than a bunch of code cites.

I agree.

I see lots of homes where plastic enters the crawl and transitions immediately to metal. However that's not what I'm referring to and I don't think that's what the OP referred to. I think he's talking about a metal service pipe and an AHJ who either doesn't know what he's talking about or he misunderstood what the AHJ was saying. If the AHJ says that it's OK to use the metal water piping as the only service grounding electrode, I'd say that he's got his head firmly planted up his bottom.

According to Hansen, if there's metal water service pipe in contact with grade for 10' or more it must be included as part of the grounding electrode system but it may not be the only electrode and has to be supplemented by at least one of the other electrodes. That's what I was trying to say above and what one of the other responders has said.

ONE TEAM - ONE FIGHT!!!

Mike

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We (Chicago) have to extend the GEC, continuous, all the way to the water service entrance; we can't just tie to an adjacent cold water pipe.

Is that required elsewhere? I'm not a NEC guru; does it mention it in there?

The NEC requires that the GEC connect to the metal water pipe within 5' of the point where the water pipe enters the building. 250.52(A)(1)

In Chicago, where, exactly, would you typically find the water service entrance?

- Jim Katen, Oregon

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What if an overhead electric line fell onto your car while you were sitting in it? Would you be afraid?

Same thing with pipes and plumbing. Live electric lines can touch these pipes and send the electricity throughout the entire plumbing system.

There are plenty of stories about people being shocked from their shower, a faucet, and plumbers being shocked while working on the plumbing.

A recent problem with plumbing is that people replace metal pipes with plastic pipes. And only sections, not the entire pipe system. So this may leave portions of metal pipe which are not bonded to ground.

Here they are discussing Washington State and a proposed new rule that plumbers must install bonding wires when replacing sections of metal pipe with plastic...

http://www.terrylove.com/forums/showthr ... e-Plumbers

True story,

About 9 years ago I wrote up a house where the bonding cable and clamps were left hanging next to the water heater. The owner made a stink and said that Washington Energy Services had installed the water heater and knew what they were doing. She insisted I call the guy who'd installed it. I did. He got on the phone and asked me if I'd ever gone to disconnect a water meter and been knocked on my ass by an energized pipe. I admitted that I hadn't. That, he said, was the reason he had been disconnecting bonding cables for more than 15 years. I surmised that a simple set of automotive jumper cables clamped to the lines on either side of the meter might have prevented that from happening. Then I asked for his fax number and told him I'd be sending him some stuff that night. That night, I copied and sent Hansen's chapter on bonding to the guy.

The next day I got a call from the guy. He was all apologetic and thanked me for sending the documents over. He said something like, "Sh**, what am I going to do about all of those thousands of disconnected bonding cables?" I suggested he start incorporating safety checkups into his daily routine and start retracing his steps through their records and find and fix 'em all.

It's not just some of us that have trouble with this; by the number of unbonded, or incorrectly bonded, systems I see that are done by "real" electricians, I'm sure it's epidemic.

ONE TEAM - ONE FIGHT!!!

Mike

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Front of the house; basement floor. It's gotta tie in on the service side of the meter, i.e., on the service pipe. Never heard about the 5' part.

The 5' thing is fairly new. Used to be we would bond in the first convenient connection between electrical and plumbing. It's often under the kitchen sink.

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Front of the house; basement floor. It's gotta tie in on the service side of the meter, i.e., on the service pipe. Never heard about the 5' part.

The 5' thing is fairly new. Used to be we would bond in the first convenient connection between electrical and plumbing. It's often under the kitchen sink.

I think the 5' thing came in with the '96 NEC.

- Jim Katen, Oregon

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  • 6 months later...

I'm just your average homeowner and I'm reading this post on grounding. I purchased a foreclosure property in Southern CA that was in really bad shape, and one of the first things I did was to run new water service in copper (the old service, just up to the point where there was a union and it converted to copper, was PVC). The original grounding wire was bonded to the pipe leading into the house, and in addition to that, the water heater, which was in a laundry room, had a separate ground to both of the copper pipes on it, and that same ground was jumped to the galvanized gas line running to the water heater.

My plumber noted the jumping of the grounding wire between the copper water pipes and the galvanized gas line and had a fit, saying it was totally incorrect and disconnected the ground from the gas line. He cited the recent gas line explosion in San Bruno, California as one of the reasons for his actions.

I'm deep in the midst of work on the house, so to have to run a separate ground to the gas line isn't a big concern for me, but I want to know if it is necessary. Was what the plumber told me wrong,only partly wrong, or totally correct.

Thanks.

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Mr. Homeowner,

The wire connected to the gas line bonds (not grounds) the gas pipe. It is required.

Say a hot wire somehow falls on the gas pipe in the home. If that bond wire is not attached, the circuit breaker will not cut power to that circuit, thus the pipe becomes energized. If the bonding wire is attached, the circuit breaker will trip.

Tell your gas man to get a clue so that he doesn't inadvertently kill someone. If that doesn't work, mention the word "lawsuit".

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. . . The original grounding wire was bonded to the pipe leading into the house, and in addition to that, the water heater, which was in a laundry room, had a separate ground to both of the copper pipes on it, and that same ground was jumped to the galvanized gas line running to the water heater.

My plumber noted the jumping of the grounding wire between the copper water pipes and the galvanized gas line and had a fit, saying it was totally incorrect and disconnected the ground from the gas line. He cited the recent gas line explosion in San Bruno, California as one of the reasons for his actions.

The explosion in San Bruno was a gas pipeline, not a gas line in someone's house. Last I heard, the authorities who were investigating it had not determined a cause for the explosion. Perhaps your plumber should contact them and make them aware of the possibility that the pipeline might have been bonded to a water line somewhere. I'm sure they'll appreciate the advice.

I'm deep in the midst of work on the house, so to have to run a separate ground to the gas line isn't a big concern for me, but I want to know if it is necessary. Was what the plumber told me wrong,only partly wrong, or totally correct.

The plumber was totally wrong. The gas pipes must be bonded to the electrical system. You can reconnect the gas pipe to the bonding jumper that's connected to the water pipes. Alternatively, if you have a furnace, you can just bond the gas line at the furnace using the furnace's equipment grounding conductor.

- Jim Katen, Oregon

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