bonding the sprinkler riser

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quinn

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while passing an electrical final today, the inspector informed me that in addition to bonding the domestic water riser, I was required to bond the sprinkler riser to building steel. he cited 250, other water piping that is "likely" to be energized. my question is this. is there any situation that requires the sprinkler riser to be bonded to building steel? this riser is normal in that it is inside a school gymnasium not subject to direct lightning strikes or other transient voltage. thanks for your response
 
look before you leap...

look before you leap...

so I search some old threads, and it seems that this topic is as clear as mud. yes I have to bond the sprinkler riser, but no I cannot because it then becomes a grounding electrode. perhaps I will throw a clamp on her and carry some 3|0 up to building steel. what can it hurt. although the hangers are not listed for being energized, they are a makeshift bond. what will a little copper hurt?
 
We bond the sprinkler to the main water line where they enter the building.

It is expected and simple to do.

That said there is a good chance many sections of sprinkler pipe connected by Victaulic couplings are electrically isolated from each other.

http://www.victaulic.com/

ConfinedSpace_595x240.jpg


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Be wary of where you choose to make the connection when the building entrance riser is cathodically protected. A properly protected riser has an isolation fitting at the first flange so if you use a water clamp immediately at the point of entry and before the isolation fitting you will screw up the cathodic protection and the balance of the system will not be bonded properly.
 
Over they years I have found the situation to be clear as mud also.
Looks like if that 3/4 copper domestic water line is a good grounding electrode, that 8" iron pipe might be also :)
At one time I asked for it to be used as a grounding electrode noting, as others have said, that you would need to attach ahead of any victaulic couplings. I have also had my knuckles wrapped by the Fire Marshall who states wording in the fire codes that the "sprinkler can not be used for grounding" or something very similar to that effect. That wording, to me, leave a bit to be desired.
Is making it a grounding electrode using it "for grounding" or is that wording left over from the days when a water pipe could be used to ground ungrounded equipment ?
 
petersonra said:
Other than 250.104(B), what code would require this.
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250.104(B)

250.104 Bonding of Piping Systems and Exposed Structural
Metal.

(B) Other Metal Piping. If 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 any· of the following:

(1) Equipment grounding conductor for the circuit that is
likely to energize the piping system

(2) Service equipment enclosure

(3) Grounded conductor at the service

(4) Grounding electrode conductor, if of sufficient size

(5) One or more grounding electrodes used

The bonding conductor(s) or 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 points of
attachment of the bonding jumper(s) shall be accessible.

Informational Note No.1: Bonding all piping and metal
air ducts within the premises will provide additional safety.

Informational Note No.2: Additional information for gas
piping systems can be found in Section 7.13 of NFPA 54-
2012, National Fuel Gas Code.
Click to expand...

If the inspector feels it is likely to become energized than its required.

Typically we have no 'line voltage' connections, the flow switches, pressure switches etc will all be 24 VDC.

Do I think its likely to become engergized? Nope.

Especially considering it is hanging from countless metal supports to building steel.

But this is one of those things that is much easier and cheaper to do than fail an inspection and have to fight it out.

I expect 480sparky to chime in and say how its always better to fight then roll over but that is all about ego, not money.
 
NFPA 13

NFPA 13

NFPA 13 is the installation standard for sprinkler systems. Section 10.6.8 forbids the use of the underground sprinkler system as a grounding electrode. However, this little section specifically mentions NFAP 780. Since the piping is continuous from stem to stern, it logically follows that unlike the domestic water pipe, it can't be used for grounding. However, this doesn't mean it can't be bonded, since the purpose of bonding is to lower the potential between the pipe and someone touching it relative to earth so they don't get electrocuted if the pipe gets energized. If you think that's unlikely, just remember that the sprinkler pipe is probably run into every space electricity is run to, and then some.

Victaulic fittings don't break continuity. Look at the illustration up thread; it clearly shows the coupling in contact with the pipe on each side of the rubber gasket.
 
Vic fittings make solid metal to metal contact with the ring on the fitting and the groove on the pipe, however IMO nothing is "likely" to become energized unless it's done intentionally.
 
iwire said:
That said there is a good chance many sections of sprinkler pipe connected by Victaulic couplings are electrically isolated from each other.
Click to expand...

don_resqcapt19 said:
Many of their fittings are listed as grounding and bonding connections, but only where the service is rated at 200 amps or less.
Click to expand...

Learned something new today, thanks.


infinity said:
Vic fittings make solid metal to metal contact with the ring on the fitting and the groove on the pipe,
Click to expand...

I guess they do, and they don't if limited in service size. :huh::?



As far as the likely to become energized part, I don't think so either for a number of reasons. But if the inspector thinks its likely to become energized there is no code section we could use to dispute their opinion.
 
iwire said:
As far as the likely to become energized part, I don't think so either for a number of reasons. But if the inspector thinks its likely to become energized there is no code section we could use to dispute their opinion.
Click to expand...


I agree, it ultimately would fall on the dictionary definition of the word likely. :)
 
The term likely to be energized is a problem area for the NEC in my opinion. I posted that question to Charlie Trout on the NECA code question of the day.
Wednesday, June 24, 2015
Question:
Re: COD answer published Monday, June 15, 2015 - Likely to become energized

Charlie,
Would you like to address the meaning of "likely to become energized"? In my opinion, non-current carrying parts of equipment are never "likely to become energized". Sure they may become energized but that is not "likely".

Full Definition of LIKELY
1: having a high probability of occurring or being true: very probable <rain is likely today>

I think CMP 5 took a step backwards as far as the enforcement of the bonding rules, when they changed the wording from "may become energized" to "likely to become energized". Anything thing that is conductive "may" become energized, but it is not "likely" that they will become energized. Under the code wording, things that are not likely become energized are not required to be bonded.

Don

Answer:
Hey Don it's good to hear from you and thanks for your comment.

The words "may" and "can" are sometimes used interchangeably in the English language, Maybe learned from children's games like "Mother May I" then later in life to "Bartender may I have another can of beer". Can is also used to mean that something is possible to happen.

But back to the NEC concept, the NEC Style Manual (available at nfpa.org, under the codes and standards tab) in 3.1 states that the terms mayor can shall not be used in mandatory rules. In 3.2 it states that "The term "may" shall only be used where it recognizes a discretionary judgment on the part of an authority having jurisdiction." So the change in 250.104(B) of the 2005 NEC to replace "may" become energized" with "likely to become energized" complies with the
NEC Style Manual.

Additionally guidance is given in in Annex B, Standard Terms, of the NEC Style Manual, "likely to become energized -- failure of insulation on"
So I think the phrase "likely to become energized" is appropriate if we consider that insulation (including the air) can eventually fail leading to conductive objects becoming energized. That is considerably different than stating what may or can become energized as anything conductive can become
energized, but that is not likely, therefore bonding is not required in that case.
Click to expand...
 
If you apply the definition in Don's post: "1: having a high probability of occurring or being true: very probable" not much is likely to become energized on it's own.
 
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