Arc flash labels

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steve66

Senior Member
Location
Illinois
Occupation
Engineer
Working on some arc flash labels, and going through the latest edition of NFPA 70E (2015). I have a few questions:

1. Is PPE required to turn a circuit breaker on or off with the covers in place?

Table 130.7(C)(15)(A)(a) seems to say PPE would not be required. But 130.5(C) seems to indicate if an incident energy analysis is performed, then you can't also use the PPE category method. That would mean I can't use the table 130.7(C)(15)(A)(a).

2. 130.5(C) states either the incident energy method or PPE Categories Method can be used to determine the arc flash PPE, but not both. Why not both? It doesn't make any sense to me.

3. 130.5 (C) also states
Code:
"The results of an incident energy analysis to specify an arc flash PPE Category in table 130.7(C)(16) shall not be permitted."
Again, why not? That table should provide PPE for the incident energy levels, so why can't it be used? Shouldn't using this table result in PPE that is equivalent to the PPE selected from table H.3(b)??

4. Is the hazard category "Dangerous" gone? My version of SKM lists a Dangerous category for any energy levels over 40 cal/cm2. It basically made the label state "No PPE found" and "Do not work on Hot." This relates back to my first question. If PPE is required to operate a breaker, and if there wasn't any PPE available for the energy level, how could anyone ever turn the breaker on or off? Is that issue gone now?

5. Is the latest version of NFPA 70E automatically required to meet OSHA compliance?
 

steve66

Senior Member
Location
Illinois
Occupation
Engineer
Remote actuator. Either portable or fixed in place.

If I were designing the system, I'd include one.

However, I'm only doing the arc flash study. And if the conditions are met, NFPA 70E table 130.7C15Aa seems to allow one to operate breakers without any arc flash PPE.

Am I wrong?
 

mayanees

Senior Member
Location
Westminster, MD
Occupation
Electrical Engineer and Master Electrician
If I were designing the system, I'd include one.

However, I'm only doing the arc flash study. And if the conditions are met, NFPA 70E table 130.7C15Aa seems to allow one to operate breakers without any arc flash PPE.

Am I wrong?

Steve,
I say the answer to your question is Yes, no PPE is required. Of course the qualifiers need to be met: installed properly; maintained; secure; no pending failure is evident.
I agree that there's confusion in the wording of 130.5(D)(3)a, and I interpret it as just not being allowed to mix methods of PPE determination - it's either the tables or the calcs. I also think that the calculated incident energy can be used to determine the PPE required from Table 130.7(C)16, and posted on the label. Still confusing though.
The facility needs to make determination of the applicability of the 130/7(C)15(A)(B) & B in their Electrical Safety Program as to how it applies to the Arc Flash Risk Assessment. My opinion is that a risk assessment applied to a 40 calorie bus would come to the same conclusion as the tables, that operating a panel meter from the face of the gear is okay to do without PPE, but with all the stipulations for the equipment.
As to your question about applicability of the current standard, 70E is a consensus Safety standard and as such is applicable upon issuance, which for the 2015 edition was around August 2014.
 

steve66

Senior Member
Location
Illinois
Occupation
Engineer
Steve,
I say the answer to your question is Yes, no PPE is required. Of course the qualifiers need to be met: installed properly; maintained; secure; no pending failure is evident.
I agree that there's confusion in the wording of 130.5(D)(3)a, and I interpret it as just not being allowed to mix methods of PPE determination - it's either the tables or the calcs. I also think that the calculated incident energy can be used to determine the PPE required from Table 130.7(C)16, and posted on the label. Still confusing though.
The facility needs to make determination of the applicability of the 130/7(C)15(A)(B) & B in their Electrical Safety Program as to how it applies to the Arc Flash Risk Assessment. My opinion is that a risk assessment applied to a 40 calorie bus would come to the same conclusion as the tables, that operating a panel meter from the face of the gear is okay to do without PPE, but with all the stipulations for the equipment.
As to your question about applicability of the current standard, 70E is a consensus Safety standard and as such is applicable upon issuance, which for the 2015 edition was around August 2014.

Thanks, that all makes sense, except one sentence:

[I also think that the calculated incident energy can be used to determine the PPE required from Table 130.7(C)16, and posted on the label.

130.6(C) and (D)(3)(a) both seem to indicate we can't do that, although I'm not sure why. If you calculate a category 3 with one method (which is up to 25 cal/cm^2), and you calculate 20 cal/cm^2 with an analysis, it seems like either table 130.7(C)(16) or table H.3b would list the same PPE.

So why the need for two tables, and why can't we list PPE on the label if we do an incident energy analysis and use table H.3b?
 

jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
PE (Retired) - Power Systems
...why can't we list PPE on the label if we do an incident energy analysis and use table H.3b?

You can.

NFPA70E is very good at saying 'what', however it is very limited in the specifics of 'how'.
130.5(D)(3)(c) allows the label to contain "site-specific PPE". Most companies, that I deal with, interpret this to mean their labels can contain PPE that has been described in their ESWP procedures.
 

mayanees

Senior Member
Location
Westminster, MD
Occupation
Electrical Engineer and Master Electrician
??

??

I'm confused about it as well Steve, so I've tried to use common sense to rationalize our approach to labeling.
130.5(C): One of two methods shall be used, not both. My interpretation of that is, as in the previous edition, don't mix methods. That's clear. But then I interpret the sentence - don't use the incident energy analysis to specify PPE - is that there still needs to be a Risk Assessment applied, so that things like operating a meter switch form the face of the gear is not the same PPE requirement as racking out the breaker. So if the site agrees that the listing on the label is a worst-case PPE requirement then it's okay.
My take on 130.5(D)(3)a is that when using the incident energy analysis, we are permitted to post incident energy and working distance. It is the employees responsibility to translate that to a PPE level, and where else can that come from but 130.7(C)(16)... so we'll print the incident energy and the associated PPE level from the table. I think that again represents a worst-case protection scheme that could be lessened by site policy with a Risk Assessment.
Hopefully it's more straightforward in the next edition, because there sure is confusion concerning the cited sections, but I think common sense says that if PPE is specified to cover the worst-case incident energy level at the corresponding working distance then we're delivering enough information to keep a worker safe.
.. comments welcomed.
 
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