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Here is my scenario: I installed a 27kw generator with automatic transfer switch at a 12 year old house. I called to have it inspected and the inspector fails the job because the existing gas lines in the house were not bonded to the panels. He says that because the plumber used CSST gas lines(the yellow flexible corrugated lines)to connect from the apliances to the galvanized piping that the system must be bonded at the point where the gas service enters the building. Has anyone else ever come across this?
It gets back to "are they likely to be energized" and that is an AHJ call. What size wire does he want you to use and will he just let you use the EGC of the circuit that is likely to energize the pipe? (usually the appliance on the end of the pipe).
That was my take on 250.104(B)

Quote
(B) Other Metal Piping. Where installed in or attached to a building or structure, a 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 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 is likely to energize the piping system(s). The equipment grounding conductor for the circuit that is likely to energize the piping shall be permitted to serve as the bonding means. The points of attachment of the bonding jumper(s) shall be accessible.
Hayes:
Welcome to ECNForums...
Here is the info over on the 'Jersey side', taken from the DCA Code Communicator back in '07, opinion of DCA Code Specialist. You can access this on line at NJDCA website.

"CSST Bonding – What is Required?
There is confusion on what is going on with CSST,
flexible gas piping, since the manufacturers have been
sending out revised installation instructions with their
material. The revisions were a result of a lawsuit in which
the court stated that the manufacturers must provide a
means to protect the CSST from lightning. The revised
instructions are requiring that the CSST be bonded to the
grounding electrode conductor.
The installation instruction requirements are not
in compliance with the currently adopted codes. The code
requires that CSST be bonded, not grounded or used as a
grounding electrode. Section 250.104(B) of the 2005
National Electrical Code (NEC) states that the equipment
grounding conductor is permitted to serve as the bonding
means for the gas piping. Otherwise, bonding is required
to be from the CSST connector coupling to the water piping.
The size of the bonding conductor is based on the rating
of the circuit likely to energize the piping system. Table
250.122 in the 2005 NEC provides the conductor size
based on the ampacity of the circuit. For example, if there
is a gas heater with no electric at all to it and the service to
the dwelling is 200 amperes, Table 250.122 states that 6
AWG copper or 4 AWG aluminum is required for the
bonding conductor.
The clamps installed on the water and CSST pipes
must be listed and labeled in accordance with Section 250.8
of the 2005 NEC. The clamps may be a dissimilar metal,
provided they are approved and listed for the use.
In conclusion, no additional bonding is required
where there is electric to any gas appliance, since Section
250.104(B) of the 2005 NEC permits the equipment
grounding conductor to serve as the bonding means for a"(gas piping system.

had an inspector in NH insist that the gas guys do the bonding

i asked 'why, i've bond wire with me in my truck'?

to which he replied that i didn't know which unions were dielectric or not

of course a VT inspector recently insisted that i DO bond the gas lines

sometimes i wish they'd all do lunch together once in a while

~S~
~s!
We had a similar issue with replacement water heaters....
Existing units (gas fired) that were installed prior to the bonding of hot & cold pipes...who installs the required 'bond'? Is an EC required? or can the plumber install the bond?

The argument was that an EC had to make a trip & install bond, and it was an 'extra' cost!

Kind of a 'don't ask-don't tell' situation!

John,

Years ago when we had to bond the gas pipes, I would run a jumper from the hot water to the cold water pipe to the gas pipe. This way everything was bonded together.
Bonding of CSST is for protection from lightning strikes in the area of the building and NOT anything to do with the wiring in the building. This has caused much confusion.
To reduce incidents of failure the manufacturer of CSST requires the gas piping be bonded where it enters the building with a bond wire, based on the size of the service or as specified by an electrical engineer.
This was all decided by lawyers NOT electricians.
As a disclaimer they also specify that in areas prone to lightning strike the building should have a lightning protection system. Lawyers again.
In Indiana CSST is not allowed to be mounted within 2 inches of any metal including duct work, water heaters and furnaces.
On one job the electrician explained the bond wire would be an extra. The service was 3,000 amp and the gas pipe was on the other side of the building. The mechanical contractor replaced the CSST with black iron. Pipe is a lot cheaper than copper wire.
Failure to bond puts the liability on the contractor instead of on the manufacturer of the CSST. There is one pipe clamp UL listed for use on the hex fitting of the CSST connector, but it should be the last choice for the bond connection. Best point of connection is on the iron pipe where it enters the building.
Originally Posted by HotLine1
~s!
We had a similar issue with replacement water heaters....
Existing units (gas fired) that were installed prior to the bonding of hot & cold pipes...who installs the required 'bond'? Is an EC required? or can the plumber install the bond?

The argument was that an EC had to make a trip & install bond, and it was an 'extra' cost!

Kind of a 'don't ask-don't tell' situation!



maybe we need new company shirts Hotone?

[Linked Image from s.ecrater.com]

~S~
AlanN:
Welcome to ECN forums!!

Yes, there is conflict with the CSST mfg instructions, and areas of the respective codes. I posted an article from the NJ DCA (State) regarding CSST above in this thread.

Within your comments above, the 'iron pipe that enters the building' is the natural gas service? Is it all iron into the ground, or just iron for the metering equipment and point of entry? Reason I ask is most here is plastic in the streets, with metal for metering and distribution on the premise.

Originally Posted by AlanN

This was all decided by lawyers NOT electricians.

isn't it time our trade decides something for them Al?

like they should all ride pogo sticks into court

UL approved of course....

~S~
~s~:

Nice shirt!!
Originally Posted by HotLine1
AlanN:
Welcome to ECN forums!!

Yes, there is conflict with the CSST mfg instructions, and areas of the respective codes. I posted an article from the NJ DCA (State) regarding CSST above in this thread.

Within your comments above, the 'iron pipe that enters the building' is the natural gas service? Is it all iron into the ground, or just iron for the metering equipment and point of entry? Reason I ask is most here is plastic in the streets, with metal for metering and distribution on the premise.



further on that Hotone, is that i've noted a number of gas line installs where the CSST is broken by iron pipe T's

so my Q would be, do these iron T's get bonded as well here?

if so, i do believe said bond would need to be accessible

so there's another potential problem (if bonding required) for say, closing up a job where the bonds may be

~S~
~s~:
AS per NEC, as I understand, The 'bonding' is thru the electrical appliances that the gas piping is connected to.

Based on that, the 'bond' throughout the piping system should be mechanically continuous, unless there are and non-metalic joints/connections/fittings. Agree??


well i'm confused Hotone

does the flex constitute mechanically continuos here?

~S~
As I mentioned confusion abounds.
The bond for the CSST at the point nearest entry into the building is for lightning.
The grounded wire to any gas appliance that also has electric, for motors, igniters, etc. provides the required bond for NEC purposes.
Bits or pieces of metal piping in the gas system, Tees, manifolds, fittings do not constitute a piping system and do not need to be bonded.
Usually the gas piping outside the building is not metal. That is another reason for not using the gas line as a grounding electrode.
Remember the CSST bond is for lightning, which can travel through the earth regardless of any metal pipe path.
Note; I was registered years ago, but re-registered when I changed computers.
Alan N. CEI-M # 138
Thanks Al

That clears it up for me

~S~
You also need to remember the "likely to become energized" language in 250.104(B). An isolated section of metal pipe that is nowhere near a source of electricity is not likely to become energized. That is where the AHJ ends up making the final call. It might be nice if there was more guidance on this but the NEC is the size of a small city phone book now wink
OK, now I'm going to be confused like Sparky...
Lightning is one of the 'un-addressed' issues in my area of NJ. No, we are not 'lightning free', yes we do have thunderstorm activity, but it's kind of a back burner thing I guess.

The CSST IMHO has it's bonding per the DCA note above.

Last plac I remember seeing any kind of lightning protection was at two country clubs I worked at.

That is one thing about living in Florida. We are very aware of wind, water and lightning. It does take a lot of the mystery out of how folks up north have so much damage from a "freak" storm that is a regular occurrence here.
Lightning protection is not really that tough and you can survive direct hits, no matter what the urban legend says. The trick is directing all of that energy into the ground and stopping the shot going toward the house. A gas line is a particularly scary thing if it arcs across a section of plastic. That becomes a BIC lighter with an unlimited gas supply. You certainly want a bond where it enters the house and I would drive a rod there, even if it was just one of those 4' telco rods if I didn't have a pretty good length of metal pipe in the ground. ... but that is just me.
John,

One of the town halls I work at has the lightning arrestor system through out all of the buildings. Here in NJ that inspection ( believe it or not) falls under the Building inspector. I watch the system as they go in and make sure they get the certification for the whole system. I have seen some strange things with lightning. I seen where a bolt of lightning went through the side of an old stucco house and hit an old shotgun laying in the attic. That was all nothing else happened. (Beside the small hole in the stucco where the bolt entered.)
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