GEC question

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No we don't, the NEC requires the sprinkler piping to be bonded it does not require it to be a GE where as in most cases with it''s dielectric unions it doesn't meet the requirement of being a GE.

Roger

Well the NEC needs to be clearer on this because I see nothing in the wording that would make me not consider a sprinkler service pipe a water pipe. Perhaps they could add a definition for "water pipe", or state that a sprinkler pipe is not to be used as a GE like they do for gas pipes.

I don't believe there are dielectric unions in sprinkler mains, besides I have a feeling not using the water pipe as a GE and claiming to the inspector, " there might be a dielectric union in it so I just didn't bother" won't go over well. That is what the supplemental electrode is for.
 

roger

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Well the NEC needs to be clearer on this because I see nothing in the wording that would make me not consider a sprinkler service pipe a water pipe. Perhaps they could add a definition for "water pipe", or state that a sprinkler pipe is not to be used as a GE like they do for gas pipes.
I do agree, it should be specifically worded that it is not to be used. Might be worth somebody making proposal

I don't believe there are dielectric unions in sprinkler mains, besides I have a feeling not using the water pipe as a GE and claiming to the inspector, " there might be a dielectric union in it so I just didn't bother" won't go over well. That is what the supplemental electrode is for.
The inspector would need to be made aware of the code that tells him it can't be used period, he would probably be glad someone told him. That actually happened on one of my projects.

What does NFPA 13 say about combination sprinkler/domestic mains?

The metalic water service pipe before any back flow preventer or separation of the two systems would be a GE.



Roger
 

infinity

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Aren't the sprinkler mains and the domestic water pipes connect together at some point whether it be in the bulding or right outside the building in the street?
 
This is interesting, If I am reading this correctly, the CMP DOES consider the sprinkler a GE, and they state they do not differentiate between different types of water piping systems.

NFPA 70 Report on Proposals A2007 — Copyright, NFPA

Recommendation: Add text to read as follows:

FPN: For further information see NFPA 13, Standard for the Installation of Sprinkler Systems and NFPA 24, Standard for the Installation of Private Fire Service and Their Appurtenances, for the limited use of these systems as grounding electrodes.

Substantiation: In the 2001 ROP code Proposal 5-165 (Log #3313) included a recommendation to revise section 250-52(A) by adding “Water Based Fire Protection Piping Systems” to be prohibited as a grounding electrode.

The panel rejected the recommendation concluding the following statement applies, “The intentional bonding of all the utilities in a building creates an equipotential ground plane that minimizes the voltage differential between the different systems under normal and abnormal operating conditions. The result is an environment safer from the hazards of electrocution and fire. (Excerpt from January/February, 2000, NFPA Journal article “Grounding, Bonding, and Sprinklers”, by John Caloggero).

There is no disagreement that the bonding of all systems results in a safer environment, however, there is a distinct difference between grounding and bonding as defined in Article 100 of the NEC.

Currently, the NEC does not appear to reference the limited use of these piping systems as part of the grounding electrode system. Therefore, the insertion of a FPN in Part B of this section referencing the limited use of these piping systems would not only be prudent, it will provide continuity between NFPA publications while achieving a more user friendly document.

Panel Meeting Action: Reject

Panel Statement:
These metal water piping systems that meet the criteria in 250.52(A)(1) are grounding electrodes naturally, and as such are required to be bonded to the grounding electrode system. A provision that allows these piping systems to be isolated from the grounding electrode system is not substantiated. The NEC does not differentiate between the various water piping systems that qualify as grounding electrodes, neither does it exempt any.

Number Eligible to Vote: 15

Ballot Results:
Affirmative: 15

Submitter: Ryan Jackson, West Valley City, UT

Recommendation: Revise as follows:

(B) Other Metal Piping. Where installed in or attached to a building or structure, metal piping system(s), including gas piping and fire sprinkler 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 uses. 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.

FPN: Bonding all piping and metal air ducts within the premises will provide additional safety

Substantiation: There is a long-standing debate as to whether fire sprinkler piping is a 250.104(A) or 250.104(B) type of piping. I have spoken with several code experts on this issue, including multiple members of Panel 5, and have received different answers on this issue. Accepting this proposal would end this debate, and would be a step forward in the uniform interpretation of this rule, which is something that we should all be striving for.

Panel Meeting Action: Reject

Panel Statement:
A metallic fire sprinkler piping system is metal water piping system that is covered by Section 250.104(A). Section 250.104(A) does not differentiate or exclude between the various types of metal water piping systems that might be present in a building or structure. Section 250.104(B) covers metal piping systems other than those metal water piping systems covered by 250.104(A).

Number Eligible to Vote: 15

Ballot Results:
Affirmative: 15
 

anthonysolino

Senior Member
Fellas, this is the code i was hopin' to make good on>>>>

250.68 C Exception: In industrial, commercial, and institutional buildings or
structures, if conditions of maintenance and supervision ensure that
only qualified persons service the installation, interior metal water
piping located more than 1.52 m (5 ft) from the point of entrance to the
building shall be permitted as a bonding conductor to interconnect elec‐
trodes that are part of the grounding electrode system, or as a grounding
electrode conductor, if the entire length, other than short sections pass‐
ing perpendicularly through walls, floors, or ceilings, of the interior
metal water pipe that is being used for the conductor is exposed.

~RJ~
I would say it is then up to the AHJ being that "interior metal water piping" is not defined but I would guess that they would be talking about a copper piping system due to the simple fact the impedance of sprinkler pipe might be very high due to its metal composition typically all those connections are threaded. it would not be an effective grounding electrode thats the only thing I can see?:rolleyes:
 
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