2009 NFPA 70E / Impact to Utility

[saladhawks]

In an ironic twist, having provided the Utility Fault Current data to a multitude of customers in order for them to complete Arc Flash Studies, I have been informed by my Utility Safety Officer that we will need to complete our own Arc Flash Study per the requirements of the 2009 NFPA 70E. In the exact words of the Utility Safety Officer, "Do we have the appropriate labeling for Arc flash and PPE for every piece of equipment in our system?"

I am specifically interested in the phrase "every piece of equipment in our system." I realize that an Arc Flash Study will need to be completed for all electrical panels in our power plants and similar studies for all substation switchgear, but what about overhead distribution, underground vaults, padmount transformers, building transformer rooms, etc., etc., etc.

I honestly do not think it would be feasible to complete an Arc Flash Study "for every piece of equipment" at a Utility. Too many day-to-day changes in terms of circuit switching and subtransmission ties. How are other U.S. Utilites planning to address the 2009 NFPA 70E requirements?

 

[Zogzog]

Utilities fall under the NESC, not the NFPA 70E, but inside the power plants this is a gray area, I will let the other utilities chime in on that.

However, you dont need to do the analysis on every peice of equipment, IEEE 1584 references equipment <240V and supplied by <125kVA transformer as the line where you dont need an analysis because an arc would not be self sustaining.

But, you still need to label the equipment (As defined in NEC 110.16) with either th PPE required or the Ei per the 2009 70E.

I know this wont answer all of your questions, but will get you started.

 

[gobblerhuntr]

I am in the middle of a study at our utility and there is a good forum called arcflashforums.com that will give you more info than you want. Every piece of equipment on your system is not what the law says. It mentions everything over 125 kVA and above 208 volts I believe (could be wrong on that if so someone please correct me). Labeling is required and proper PPE for all workers. Read up on that site, it is run by a gentleman who put on a two day class I attended and is really good.

 

[stevenal]

I see no grey here.

(A) Covered. ...
(4) Installations used by the electric utility, such as office buildings, warehouses, garages, machine shops, and recreational buildings, that are not an integral part of a generating plant, substation, or control center.


(B) Not Covered. This Code does not cover the following:
(5) Installations under the exclusive control of an electric utility where such installations
a. Consist of service drops or service laterals, and associated metering, or
b. Are located in legally established easements or rights-of-way designated by or recognized by public service commissions, utility commissions, or other regulatory agencies having jurisdiction for such installations, or
c. Are on property owned or leased by the electric utility for the purpose of communications, metering, generation, control, transformation, transmission, or distribution of electric energy.

NESC does require utilities to address arc flash as of Jan 1, 2009. Your saftey officer is not entirely wrong.

 

[Zogzog]

Agreed but where the grau area will be is when OSHA 1910.269 which does cover these installations finishes adopting the 70E, that will be interesting.

Arcflashfourms has an area dedicated to NESC.

 

[wbd]

First off, you are not bound to NFPA 70E as others have noted but NESC is applicable.

NESC does not require labeling only that positive procedures are utilized to secure compliance with the rules. Section 410 A.5.

I do agree that there is a grey area having done studies for industrial and on a utility. The area is in power plants, especially with auxiliary eqpt. NESC states that for secondary systems <1000V, in lieu of performing an arc flash analysis a min of 4 cal system shall be required. It also mentions work rules to limit exposure. My concern and experience has shown that a 4 cal system would not protect and that the same IE in an industrial area would be a Category #2 per NFPA 70E. What makes an arc flash hazard any less dangerous in a utility power plant versus an industrial plant?

Go to arcflashforum.com as there are discussions on this there.

 

[apowerengr]

salad - I don't know where you're working but be aware that in the US not all states adopt part 4 of the NESC which contains the work rules you are asking about. As others have stated NFPA 70E is not applicable. I've personally completed arc flash studies for over fifty utilities - many utilities are compliant with the NESC part 4 rules.

 

[wbd]

Regardless of whether or not a state has adopted Part 4 of the NESC, I think OSHA would cite you under the General Duty Clause as arc flash hazards are a known industry hazard, there are ways to mitigate it and the employer has a duty to protect employees from known hazards.

 

[bertisevil]

Not necessarily so, wbd. OSHA may not have jurisdiction over that utility and thus would not have any power to site anyone.

Depending on the area of work (see stevenal's thread), NFPA or NESC may or may not apply.
Depending on the laws (state or local governments may or may not adopt the NESC), NESC may or may not apply.
Depending on the nature of the utility (public, private, municipal, coop, etc.), OSHA may or may not have jurisdiction.

B

 

[dpc]

What's an example of a utility that is not subject to OSHA - other than military?

 

[cranky108]

Municipal.

Since many federal goverment agencies are limited to "Interstate commerence" that can have an effect on who they regulate. Although they will say otherwise.

 

[wbd]

Well, let's look at this another way. The bottom line is that every employer needs to provide a safe working environment for the employee's. Is the argument that all the requirements for arc flash hazards don't apply because it doesn't specifically say or that the regulatory agencies are years behind the standards/practice going to hold water in a courtroom over an injury? Why argue over what applies and what doesn't instead of what is the safest thing to do?

 

[cranky108]

I don't disagree with wbd, but when the standard specifically states it does not apply.

With two standards there will come a point where they will diverge which is when you must choose which to follow.
I suggest applying the standard that does apply which is NESC.

 

[wbd]

Well, maybe I'm more conservative when it comes to safety but if there is a standard or method that would provide more accurate AFH results to enable better protection, I will use it.

IMHO, I believe NESC is lacking in the area of <1000 V and I will use NFPA70E/IEEE 1584 for inside my power plants.