Bonding black iron gas piping

I was recently informed by a N.C. licensed electrician that iron gas piping does not need to be bonded to the G.E.S. ever!This is contrary to what I have learned.I can find no information to substantiate this idea If you have a difinitive answer please post it!

The electrician is incorrect. All metallic gas piping must be bonded to the grounding electrode system.

250.104 (B) Other Metal Piping. Where installed in or attached to a building or structure, metal piping system(s), including gas piping, that is likely to 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.

If the iron pipe connects to a furnace, it achieves the bonding through the furnace gas valve where it mounts to the cabinet metal. The furnace cabinet metal is bonded where the 120V branch circuit enters.

If there is no CSST gas piping, this is considered the bond in this area.

When you also have CSST in the house AND it was built after the new rules about CSST came out then you need ADDITIONAL bonding. This is typically done near the gas service meter with a clamp around the iron pipe connected to the GEC.

The electrician is not necessarily incorrect:

Keep reading to where it says “The equipment grounding conductor for the circuit that is likely to energize the piping shall be permitted to serve as the bonding means”

That being said, many areas, including mine, require bonding independent of the circuit likely to energize, probably because most of our furnaces are plug and cord. It might not be required be in Robert’s area, since it is really a local amendment.

Good info…thanks.

I hear ya Brian, but this is what I read.

The bonding is required, however, it may be located somewhere other than at (or near) the gas main.

Got it

So how does on determine what piping is “likely to become energized”? It seems that the code writers left the requirement open to some interpretation.

Do you want to know how a Municipal Inspector determines this on a code based inspection?

1.) If the piping supplies an appliance that is electrically fed. If the circuit has an EGC then 250.104 covers them generally ( exception would be CSST based on the manufactures additional wants and demands…lol)
2.) If we see NM Cable wrapped over piping and so on within the structure during the rough in inspection, we would note this on the inspection ticket for the next inspector to be aware of on his final inspection.

This is very hard for an HI to determine, while you cant see in the walls usually, you end up having to rely on connections by 250.104 compliance.

Now it can be looked at in many ways…depending on the installation and workmanship of the application we could say it is always likely to become energized but if that was the intent the NEC would just say always bond gas piping and get rid of the “likely to become energized” mumbo jumbo…so in the end it is another area of the code that is not black or white…just more so the color of interpretation.

When I inspect a municipal job or if I am training a new inspector I ask them questions to juggle their mind, if the quality of workmanship leaves him shaking his head in amazement and their is NM Cable everywhere or other cables as well so lets not throw them out of the mix…I ask them…in your opinion is their any “likely” chance a cable could cause the piping within the dwelling to become energized and then I wait for their answer…if the work is very sloppy, cramed in holes with copper plumbing pipes or gas lines and what have you the answer is usually yes…then I ask them does 250.104 solve the issues with the system…if not in their specific application I say them make them bond the gas line or water line…and be done with it.

If you bond anything electrical to a gas pipe in Rockland, Orange, parts of Northern NJ, LI, and especially NY City, Consolidated Edison will immediately turn off both the power and gas to the dwelling.

The utility is the ultimate AHJ, and their rules are the only rules that count. There rules override all others.

So, before we go off quoting codes, my advice is to find out what the utility requires and accepts.

Well you can QUOTE the rules in those areas but the rules in Richmond ,VA is if we determine it is likely to be energized and will require it. Once we have established this, it is done on the inside of the dwelling in an accessible area. If the power company chooses to remove it or demand it after the inspection thats not up to me or my inspector…we employ the USBC, IBC and IRC and by reference the NEC and we do not enforce the BlueBook by the utility.

Everywhere is different…so if you make a statement about “going off quoting codes” be sure you also know each jurisdiction as well because they change in every part of the country…and I dont live in Rockland, Orange and Northern NJ…thank GOD…lol

That would be the street side. No where that I am aware of are you allowed to bond to the street side of a gas line. The street side is isolated from the house side by a non conductive meter or fitting.

As far as bonding to the house side, the minute you plug in your gas range or your gas furnace you have bonded the electric service to the interior gas lines.

As usual, it is “clear as mud” from a HI’s point of view. Of course, the AHJ always has the last word, but you have to wonder what the code-writers were thinking.

What we bond in our own dwelling is for OUR safety…I dont care what the utility says about bonding within the dwelling. If the gas piping inside the dwelling is determined to be “likely” energized we will bond to it…end of story.

If we determine it is not “likely” to become energized we wont…and in most all cases 250.104 will take care of this for us anyway.