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PB 21
Jan 29, 2010, 07:37 PM
Hi all, anyone been forced to bond the gas meter. IF so did you size according to the Grounding Electrode Conductor and where on the meter did you bond it.

tkrussell
Jan 30, 2010, 07:19 AM
This is a confusing issue. Hopefully I can make some sense.

Being forced means being required to comply with the National Electric Code.

This requirement is stated in NEC 2008 edition:

"Section 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."


First, consult with the local gas utility to learn their requirements. Some require their systems to be bonded (correct term, not "grounded"), some don't.

Most allow the gas piping to be bonded simply by the act of grounding ( I know, now I am switching gears on you with the terms) the gas appliance being served by the equipment grounding conductor in the electrical circuit supplying the gas appliance.

This would be the EGC that is sized per Table 250.122. If a gas furnace is fed by a 20 amp circuit, that circuit needs a #12 EGC, and, as I said, most gas utilities are satisfied by that circuit and EGC the gas line is sufficiently bonded. If a bonding jumper is needed, and the gas line serves an appliance no more than 20 amp circuit, only a #12 wire is needed as an bonding conductor.

The following links are examples of what I am trying to explain, how to bond, and one that does not want bonding done.

http://www.safetyauthority.ca/bcsa_pdf_files/bonding341.pdf

Do not use the gas meter for electric bonding (http://www.parisnaturalgas.com/PHCPUD/index.php?option=com_content&view=article&id=78:gas-meter&catid=38:emergency&Itemid=56)

Bonding Metal Gas Piping | IAEI Magazine Online (http://www.iaei.org/magazine/?p=4186)

You specifically mention gas meter. I don't thnk the intent is to connect a bonding conductor directly to the meter, but a ground clamp attached to the gas pipe on the customer side of the meter is usually sufficient. Again, checking with the gas utility should help with this connection.

Did any of this help? Get back with your situation. Who is requiring this? Who is your gas utility?

PB 21
Feb 2, 2010, 06:51 PM
Hey TK sorry I didn't get back sooner, Basically this is the situation. Homeowner had new hvac system installed and the HVAC tech uses about 10 feet of CSST. WSSC (Washington Suburban Sanitary Commission) ((Wash D.C. Area)) failed the inspection due to not bonding CSST. Ive been trying to get answers and I've been getting a lot of different ones. Actually getting in touch with the actual AHJ is next to impossible.

Things I've heard from 3 different branches of WSSC

-attach a ground (sized acc to GEC for service) from the panel to the closest accessible main gas line "downstream of regulator"

-install a brand specific ground clamp to the hex head of the connector of the CSST and run a bond wire from the CSST to either the panel, GEC or supplemental Ground

-install a #8 ground from either Panel ground bar, Cold Water Ground, or accessible Ground Rod or just install new Ground Rod close to Gas pipe or meter "can be bonded inside or outside on company or user end of regulator.

Ive got all three of these and have no idea which one is right

KISS
Feb 2, 2010, 07:42 PM
Here is some reading, hopefully, until tk can get back to this:

http://www.toolbase.org/pdf/techinv/csst_lightningconcerns.pdf

You will note that it's confusing as you state.

tkrussell
Feb 3, 2010, 05:35 AM
PB, the one I do not agree with is #3, adding a ground rod. Otherwise the other two are fine

I don't suppose you have any of these directives in writing?

It is no fun when you get multiple answers from one agency. Written instructions would help show them their inconsistencies. Of course, now is not the time to aggravate the situation.


Really need to get the AHJ for electrical to provide direction.

PB 21
Feb 3, 2010, 07:14 AM
Thanks a lot for the help guys. I went onto the website for the manufacturer Gastite and it seems to suggest bonding not to the csst itself but to either the pre-fabricated meter stub-out or to any steel pipe segment downstream of the meter. Ive decided to use the cold water ground simply because its right next to the Gas Main. I will update after I actually get AHJ out there. Thanks again to both of you.