Bonding Piping 101....Good To Know !

(4) Bonding Conductive Materials to an Effective Ground-Fault Current Path. To remove dangerous voltage from ground faults, electrically conductive metal water piping systems, metal sprinkler piping, metal gas piping, and other metal-piping systems, as well as exposed structural steel members that are likely to become energized, must be bonded to an effective ground-fault current path. Figure Above
Author’s Comment: The phrase “likely to become energized” is subject to interpretation by the authority having jurisdiction.
(5) Effective Ground-Fault Current Path. Metal raceways, cables, enclosures, and equipment, as well as other electrically conductive materials that are likely to become energized, must be installed in a manner that creates a permanent, low-impedance fault-current path that facilitates the operation of the circuit overcurrent device. Figure 250–22

Author’s Comment: To assure a low-impedance ground-fault current path, all circuit conductors must be grouped together in the same raceway, cable, or trench [300.3(B), 300.5(I), and 300.20(A)]. Figure 250–23The earth is not considered an effective ground-fault current path.

Ok…now from my portions of this educational moment on grounding the gas piping as shown above.

Lets examine Art 250.104(B)- Other Metal Piping

Ok I will try to break this down because I have had alot of e-mails on this question…Q: Do you bond the gas piping within the dwelling to the GEC and so on…ok…I will answer this under the eyes of the 2002 NEC.

Other Metal Piping Systems- Metal piping systems , such as gas or air piping which may become energized, SHALL BE bonded to the service equipment enclosure, the grounded ( neutral ) service conductor, or the grounding electrode or grounding electrode conductor where the grounding electrode is of sufficient size. The bonding jumper SHALL BE sized in accordance with Table 250.122 using the rating of the circuit that may be energize the piping. The equipment grounding ( bonding ) conductor for the circuit that may be energized the piping can serve as the bonding means.

Ok…translation- The equipment grounding ( bonding ) conductor for the circuit that may energize the piping can serve as the bonding means.

Practicle Translation…If you have a Gas cook top that has a 15A ignitor to the applicance…Do you have to BOND the gas line to it because it is likely to be energized…well YES in theory…but this is taken care of for you in the appliance itself…and completes the requirement…

Now…with that said…Remember this is looked differently at in many AHJ’s but the NEC is clear on it’s wishes…any piping even GAS lines that may become energized need to be bonded to…now here is the question…Who determines which is likely to become energized…:slight_smile: Ponder that and hope you enjoyed this Bonding Minute…:slight_smile:

If you learn anything from this…remember the EGC of the equipment the piping is run to…can function as the bond…:slight_smile:

OMG…Forgive me guys…my Question is worded AWFUL…lol…just found out I cant edit the poll question…lol…

Should be : Do Gas Piping Within Dwellings Get Bonded?

Does it get bonded? No (at least around here).

Should it be bonded? Yes. Could help make for a safer house. Costs about $10.00 max. Well worth it.

I recommend it.

Is the reason Will because of a local AHJ ruling…? I know things are a bit different in some IL areas…for example I think NM ( Romax ) in IL is looked at like a leper colony…

This is why the NEC requires it but the problem is who determines " What can become energized " is where the local AHJ takes over…:slight_smile:


Local AHJ codes are, more often than not, influenced and written and changed and modified and variances are goven based upon all sorts of reasons besides technical facts. This is a point that is often lost on consumers and by electricians and by the NEC.

Is there a common sense, technical, factual reason to ground the gas piping?

If so, I will inform my clients of it. I will do this because I work for them and have a legal and moral mandate to work for an protect my client. I do this regardless of who I p*ss off or who’s toes I may step on.

I ask you. Does bonding the ground to the electrical system make the house safer? Please answer without referring to codes or AHJs or the like. As a ‘master’ electrician, what is your expert technical opinion?


All my answers are based on what my opinioin may be…which tends to get me in trouble as if yu did not remember…lol

Please understand that “I” work with the local AHJ all the time so I am VERY aware of what local changes can mean and why they take effect.

Now before I give MY opinion I will post an example of someone Mr. Holt knew who died because of it…

The case where metal gas piping for a restaurant, with no electrical appliances became energized and killed a kitchen worker. A rat ate through the insulation of a nonmetalic-shealthed cable and the exposed conductor energized the metal gas piping system.

Now…in MOST of the homes HI’s see the wiring is well lets say at least half hazzards to begin with…another thing I see alot of someone taping Romax to gas pipes and so on and with Romax running around and on top of many metal pipes and lets just say they happen to be gas piping…their is a potential for the pipe to become energized…Now what happens if the piping is not bonded to allow a removal of dangerous voltage…who do you think gets is when you touch it…?

The intent of the NEC is a safety view point…I am VERY tired of everyone saying NEC is not Safety…YES it is…in fact the NFPA publishes the NEC…every code issue could be an argument for Safety…They MUST go hand in hand…

No CODE should not be quoted…but on a message board their is nothing wrong with posting the code so inspectors LEARN from it…not to quote it on the job…

If the home inspector can’t understand that…they need to change fields…

ok…you asked :

I am not sure what you are asking…did you mean to say is bonding the gas piping to the grounding system make the house safer?..Yes, it can…

Are you asking does the ground system itself make a house safer…Yes, intentionally connecting to earth througha ground connection help prevent build up of voltages that may be hazzardous to equipment or persons.

Hi to all,

Here is my take on codes (and no we are NOT code inspectors).

Codes only exist due to recognition of previous failures, for example GFCI’s were developed to meet the need to protect people from electrical shocks, why? because people were dying from electric shocks, simple really.

Its not a code issue per se it all about safety issues, any AHJ may decide to implement a lower standard, but that does not make it a best practice decision.

As to Bonded gas lines, if it saves one life a year it was worth the code being there, if it fails to save a life in Illinois because it was not adopted as best practice and a requirement, then that would be a failure of the AHJ not the code.

Are we not as home inspectors interested in best practice?



Another example…

Your local HVAC guy is in the crawl space of a dwelling and working on some duct work…Ok the old fella is tired and it has been a long day…

The crawl space is FULL of ROMAX everywhere…running over pipes, under pipes…around pipes…and as we all have seen…Taped to pipes…

Now there is a live wire touching the piping system ( yeah, it could happen ) and the old house has a gas furnace…so their are gas pipes under the house as well…

Now that old fella is tired right…so he rests one hand on the gas pipe and one on the ground to gather his breath…

Now…Would you NOT want your gas pipe bonded at this point or would you prefer to pick out the pine box to tell his wife he will be coming home in?

Sorry, Paul. What I meant to post was ‘does bonding the gas piping to ground make the house safer’. I mis-typed.

I agree with you.

My opinion of the NEC is high, yet you must agree, they are also and AHJ, at least in the case of national recognition. At least they are ‘acting’ like an AHJ.

They are also vunerable to ‘political’ pressure. If you don’t see that, please look up the word ‘political’. Politics is not limited to gevernmental groups. That is very clear from all the recent NACHI posts and from other posts from certain people who have ‘agenda’. Politics is balancing the good against the agendas, by using the ‘art of the possible’.

Your example could also be used as an agrument against ROMEX. Does the NEC speak against that? (Really, I don’t know. Never looked it up.)

Giving HIs insight into the process, but there is always the temptation for HIs to join that process. This cannot occur. HIs are independent and work for our clients based upon safety and as a guard against liability. Codes and AHJS do not address these issues in clarity, only with regards to politics.


Actually this is the stuff I like Will…Things like this help people LEARN.

To be honest with you thats is what is funny about Illinois in that ROMAX is a legal wiring method in most areas and is VERY safe. The NEC approved the use of Romax ( which is a trade name really…) for use in now an even larger and expanding building structure…heck now some commercial applications are in non-metallic cable…

The NEC really does not govern RATS…lol…and it has specific guidelines for NM Cable installations but using Conduit in dwellings to me is barbaric…but thats my opinion…I guess I could run AC cable in a dwelling but…man thats so much overkill in my views.

As for politics…I agree…No getting around that part I guess but I would say it really depends on the area because most of the AHJ’s I speak with and work with rule according to the NEC 99% of the time…they only bring in their own views and rule on them when a arguement is presented to them the NEC does not clearly explain.

I guess the NEC is like the Bible in a sense…you have so many ways to look at things you are bound to have different views…Ie: Baptist, Prodest, Methodist and so on…still same bible…get what I mean…:slight_smile:

I can tell you this…I would NEVER wire anything in Illinois…If I can’t use NM Cable…for residential anyway I aint wiring it…lol

I always used the principle that gas pipes should be bonded by the EGC of the circuit likely to energize it. I made sure the pipe to a heater or furnace was bonded to the igniter/fan circuit. The only time it gets tricky is if there are no electrical componants to any of the gas equiipment. Now you are just guessing where to bond (there may be multiple dielectric joints) and what size bonding wire to use.


I hear ya brother…the NEC would try to give example of ANY electrical wiring that runs on, accross, and based on the local AHJ it could be simply NEAR the piping and require it to be bonded.

I think in lack of the EGC to be able to size it as you explained on the equipment that does have a circuit to it…you would size in accordance with 250.122 using the rating of the circuit near the piping…with the majority being probably 15A or 20A circuits…yes…begins to get tricky…lol

I would tend to lean towards…screw it…take a # 6 AWG and bond to it and be done with it…lol

You’re good Paul…:smiley: :D… :smiley: …and make sense…:smiley:

Paul, you’ve probably got a reason to, but why do you call NMC, Romax instead of Romex?


It must be difficult for you, switching between the code inspector and tyhe home inspector modes. Two totally different standards or practice and all that.

Probably because I cant SPELL for crap James…yes it is Romex which is really just a brand name…thanks for pointing out I failed spelling in school…:)…Also I am only about 30 miles from West Virginia if that tells you anything…

I probably should just call it what it is…Non-Metallic Sheathed Cable…as it is safer…thehee

Will…I FIGHT it every day brother…I walk into a house giving an electrical quote and my INSPECTOR vibes start going off…and visa versa…when on an inspection…I struggle with NOT going too far all the time…

But it really is fun…having LOTS of knowledge and trying to figure out what to do with it can be both fun and nerve racking at the same time.

I knew there was an explanation. Yeah, the Romex name is what 99% of non elecricians know NMC by. In fact, in my reports if I refer to it as non-metallic sheathed cable or as NMC I usually put (Romex) after the first reference just in case they don’t know.

Maybe it is I am southern…lol…Maybe it sounds like ROMAX when it comes out of us southern folks mouth…lol…

Romex is the registered trademark of the Rome wire and cable company (now Southwire). The real name is type NM-b.
NMC is another product, I doubt most of you have ever seen. It is damp location NM with a plastic inner wrapper where the kraft paper is now. When I look it up, the major cable companies refer you to type UF. I am guessing nobody makes it for the US market. Maybe that is different in the Great White North.

Yeppers…and they even name NMS now…

NM- The overall coating SHALL BE flame retardant and moisture resistant.

NMC- The overall coating SHALL BE flame retardant, moisture resistant, fungus resistant and corrosion resistant.

NMS - The overall coatin SHALL BE flame retardant and moisture resistant. The sheath SHALL BE applied so as to seperate the power connectors from the communications and signaling conductors. The signaling conductors SHALL BE permitted to be shielded. An optional outer jacket SHALL BE permitted.

Now the NMS I can safely say I have never used that I am aware of…