Grounding to gas line

[rkithil]

Saw a bonding strap from a metal gas line to
a nearby ground wire from a lightnng
protection system. Seems nuts to me.
Cant find anything in NEC. Help ????

 

[charlie]

Re: Grounding to gas line

Saw a bonding strap from a metal gas line to a nearby ground wire from a lightnng protection system. Cant find anything in NEC.

Wrong Code, check out the lightning protection and the fuel gas Codes.

 

[hurk27]

Re: Grounding to gas line

I dont think I would want to be around when a lightning strike took place.

 

[luke warmwater]

Re: Grounding to gas line

If this is the wire going to the ground rod, then No.
If this is the wire going to the copper water line, then Yes.

 

[don_resqcapt19]

Re: Grounding to gas line

hurk,
Actually I wouldn't want to be in the area without the bond in the event of a lightning strike. If it is within 6' of a lightning protection system conductor and not bonded, a "side flash" between the lightning protection conductor and the unbonded gas pipe is likely to occur. I believe that NPFA 780, the Lightning Protection Code, requires all metal object within 6' any part of the lightning protection system to be bonded to the lightning protection sytem.
Don

 

[charlie]

Re: Grounding to gas line

Don:

I have copied part of section 250.106 as follows:
Lightning Protection Systems.
The lightning protection system ground terminals shall be bonded to the building or structure grounding electrode system.

FPN No. 2:Metal raceways, enclosures, frames, and other non?current-carrying metal parts of electric equipment installed on a building equipped with a lightning protection system may require bonding or spacing from the lightning protection conductors in accordance with NFPA 780-1997, Standard for the Installation of Lightning Protection Systems. Separation from lightning protection conductors is typically 1.8 m (6 ft) through air or 900 mm (3 ft) through dense materials such as concrete, brick, or wood.

The NEC doesn't normally require the gas piping system to be grounded; however, if the lightning protection system is close to the gas piping system, you are correct, it has to be bonded. Sorta looks like my first statement was not correct, HUH?

 

[don_resqcapt19]

Re: Grounding to gas line

Charlie,
What about 250.104(B) for gas pipe bonding?
Don

 

[charlie]

Re: Grounding to gas line

Don
It is generally not required to bond to the gas piping system. An error during the attempt to make Article 250 more user friendly screwed that one up and it has been fixed in the 2002 Code.
Charlie

 

[don_resqcapt19]

Re: Grounding to gas line

Charlie,

250.104(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.

This is also required by the Fuel Gas Code. The common interpretation of this is that if any gas appliance has electrical power to it, then the gas piping is likely to become energized. In most cases a separate bonding conductor will not be required as the appliance EGC will be mechanically bonded to the gas pipe at the appliance, but the result is that the gas piping is bonded to the electrical grounding system. The wording that was in the '99 code as 250-104(b) was a direct quote from the Fuel Gas Code and it appears that the Fuel Gas Code always requires that the gas piping be bonded, even where not connected to an appliance requiring electrical power.
Don

 

[michael nye]

Re: Grounding to gas line

Thankyou for that very well put and informative explanation of grounding the gas pipe.

 

[charlie]

Re: Grounding to gas line

As a matter of interest, this is a correspondence I received after the last Code cycle (sorry, I no longer have the date since this was imbedded in another document). The topic was the 1999 NEC and John has been hit with the sunset rule so he is no longer the chairman of Panel 4. You can see from the correspondence that the common interpretation is not the intent. Also, the intent is not enforceable, just the interpretation of the AHJ. I trust this is of value.

Just so you know....the NFPA-54 (National Fuel Gas Code) Committee has issued a Formal Interpretation of the NFPA-54, 3.14(a) which pertains to NEC 250-104 and electrical bonding of gas pipe. I attended the NFPA-54 Meeting in San Antonio, Texas (end of February) and was asked to speak on this issue. I did so and so did Ted Limoff of NFPA Staff.

The statement of issue and question asked were:

NEC 250-104(b) states: "Each aboveground portion of a gas piping system upstream of the equipment shutoff valve shall be electrically continuous and bonded to the grounding electrode system."

"Is it the intent of NFPA-54, 3.14 (a) and NEC 250-140(b) (metal gas piping), to consider this bonding requirement to be satisfied where a grounded gas appliance is attached to the metal gas piping system?"

The answer was: "Yes"

The intent expressed by the Committee is that when connected to grounded equipment (e.g. equipment connected to an equipment grounding conductor) the pipe is considered bonded.

I was asked to keep the NFPA-54 Committee appraised of this issue, informed if further clarifications were considered needed, and asked to kept them informed of Panel 5 Actions pending on Proposals 5-64 & 5-65 (removal of the phrase "likely to be energized") or which I intend to send in a Comment to Reject. I believe in the zeal of grounding and bonding, Panel 5 is, unfortunately, and unwittingly creating safety issues and concerns for systems regarding which they have limited exposure and knowledge.

John Beck
Pacific Gas and Electric Co.
Chairman CMP-4

 

[ffalcon34]

Re: Grounding to gas line

from what i see nec article 250.104(B) states
that gas piping shallbe bonded to the service equipment

 

[tom baker]

Re: Grounding to gas line

Regarding bonding to gas piping systems:
1. On the Gas company side of the meter, they do not want you to bond to it as their piping is cathodically protected. Your bonding will disturbe and upset the cathodic protection
2. At the gas meter is a di-electric or insulating union.
3. Most gas piping is poly to the house. Some of the distribution mains are poly.

 

[charlie]

Re: Grounding to gas line

from what i see nec article 250.104(B) states that gas piping shallbe bonded to the service equipment

"250.104(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 . . ."

Surely, we don't have to explain what "is" . . . UH . . . "may" means. LOL

 

[bennie]

Re: Grounding to gas line

Charlie: Does this mean that metal duct work may not become energized?