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 Post subject: OSHA 1910.269 vs NFPA 70E PPE Requirements
PostPosted: Tue Feb 28, 2017 7:53 am 
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Location: Rutland, VT
In the OSHA regulation for utilities, the emphasis seems to be for open air type faults and the associated PPE for those faults. However, since this covers utilities, many have power plants and substation with switchgear and rackable breakers for the distribution feeders.

Although it seems that the power plant and equipment would fall under OSHA 1910.269 arc flash, this equipment is closer to the type that is in industrial facilities and should be treated as such. However there is no wording I could find in OSHA on this so it appears that for PPE the OSHA requirements are used.

My concern is that in OSHA 1910.269 Appendix E the table that lists minimum head and phase protection for a 3 phase fault indicates None for 2-4 cal/cm2, Arc Rated Faceshield of 8 cal/cm2 for 5-8 cal/cm2 and Arc Rated hood or faceshield with balaclava for 9 cal/cm2 or higher.

Now if you contrast that with NFPA 70E-2015 Annex H PPE requirements, these requirements are stricter than the OSHA requirements even though the equipment is very similar (ie box).

Anyone have insight on this or way to proceed?

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 Post subject: Re: OSHA 1910.269 vs NFPA 70E PPE Requirements
PostPosted: Tue Feb 28, 2017 10:17 am 
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To be sure, I have customers in both jurisdictions plus others. So I work with whatever I'm given on a given day. I use the expression, "When in Rome, do as the Romans do." Utility workers have their standard, and industrial workers have theirs. And a whole lot of sites out there don't even do that much.

If you read the entire 1500+ page justification document on 1910.269 (I have), the assumption that most exposures are outdoor installations is definitely correct and despite the fact that the PPE variations are based on somewhat tenuous arguments in the first place, 70E is on similar shaky ground. By that I mean that at first glance all of this seems to be based on sound science but as you dig deeper into it, you quickly realize that both are based quite a bit on some speculation and pseudo-science.

To this I would say that 1910.269 is mandatory. 70E is voluntary and only gets teeth due to the general duty clause. Protection from arcs is only generally mentioned at all anywhere in Subchapter S (1910.3xx) which applies to utilization equipment. And when we get down to it, 1910.269 especially in Annex A lays out clearly that when you have mixed jurisdictions, you apply both standards simultaneously. In that case 1910.269 prevails since it has specific arc flash requirements while Subchapter S does not.

Although it looks like the PPE requirements are stricter, that is not necessarily the case. One other major difference is that 1910.269 mandates calculating distances based on normal working distances to the chest which is only 15", based on the idea that utility workers in rubber glove work method are directly manipulating energized conductors as opposed to IEEE 1584 which uses a range of values from 18 to 36" based essentially on the position of the worker assuming they are working on equipment in the box but that the exposure is to the bus bars at the back of the enclosure. You will also no doubt notice that 1910.269 uses 2.0 cal/cm2 as the lower cutoff while 70E uses 1.2 cal/cm2. Part of the justification for the higher cutoff is that as you get closer to the electrical source following the general principles of coordination, the timing on protection relays necessarily has to get slower. The Stoll curve continues to increase with long trip times. There have been proponents of the idea of using heat flux instead of heat energy which should be a constant but so far that has not gained traction anywhere.

Finally there is a bit of a difference in how utility workers are treated compared to the general case. Under 1910.269, everyone must be a qualified worker while under Subchapter S this is not necessarily the case. You get two different treatments as a result. For instance with substation design (IEEE 80) in terms of grounding, it is acceptable to allow workers to receive a shock as long as it doesn't kill them while under Subchapter S the goal is to keep shock to under the perception level (<5 mA vs. <100 mA). It seems from my reading of both standards that at the end of the day the goal is purely survival and not preventing burns entirely. 1910.269 appears to take a different view on this compared to 70E. While 70E attempts to prevent burns altogether the underlying design theory for the standard in terms of PPE simply doesn't support this while 1910.269 doesn't attempt to go there in the first place. What I mean about 70E for example is that ATPV is a 50% threshold for potential 2nd degree burns. A few data points above and below this threshold allow enough heat through to have a second degree burn. Numerical simulations within IEEE 1584 show that it will meet this threshold (50% chance of a second degree burn) using the calculated incident energy for the empirical equation approximately 90-95% of the time. The remaining 5-10% of the time, it doesn't provide adequate protection and then after that, 50% of the time the incident energy can exceed the ATPV rating anyways. That's just the numerical side of it. Couple that with the fact that the 18-36" working distance is making a lot of assumptions about body position and completely ignores hands and arms and focuses purely on the head/chest area, and the fact that it's based on a total heat absorption assumption and not heat flux, and the science behind 70E quickly falls apart just as it does with 1910.269.

On top of all this, from a purely administrative point of view, think of the problem of explaining why the two different situations differ and why the same worker has to wear a certain set of PPE for a particular situation and an entirely different set of PPE for a different situation even though they both have identical incident energy values (well, maybe almost identical). Let's just say that this can quickly turn into a situation where nobody knows that is right and what is wrong.


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 Post subject: Re: OSHA 1910.269 vs NFPA 70E PPE Requirements
PostPosted: Mon Mar 06, 2017 9:53 am 
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We have performed many Arc Flash Studies for power generation facilities (power plants). We use IEEE 1584 and NFAP 70E throughout the facility. The only deviation to this is some outdoor substations with open exposed bus. We sometimes use a different method of calculating the AF energy but will still use NFPA 70E for the recommended PPE.

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 Post subject: Re: OSHA 1910.269 vs NFPA 70E PPE Requirements
PostPosted: Mon Mar 06, 2017 11:41 am 
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In the annexes to 1910.269, OSHA recommends IEEE 1584 empirical equations under 15 kV. Above 15 kV, they recommend ArcPro. However OSHA also uses a 2.0 cal/cm2 cutoff and changes the working distance to 15" whereas IEEE 1584 uses different working distances. There are some differences in terms of required PPE although with respect to PPE, the NFPA standard is more stringent. So if your calculations don't reflect the current OSHA 1910.269 regulation, you are in violation of the regulation which trumps voluntary safety standards.


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 Post subject: Re: OSHA 1910.269 vs NFPA 70E PPE Requirements
PostPosted: Wed Mar 08, 2017 7:38 am 

Joined: Tue Sep 17, 2013 7:35 am
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As a person who works in a Gen Station, it's nice to see a topic covering Generation. 269 leaves us in limbo because our hazards are in the box and the faults covered by 269 are open air. I argued successfully on that point and we finally did a IE study and dress per the label, prior to that Arc Flash PPE was based on voltage level alone. Imagine their surprise when they received the study results.
I would like to comment on Paul's remark that Generation is treated differently because everyone in Generation is "Qualified". I have been trying to explain this to management for over a decade. Let me tell you, close to nobody in our fleet is "Qualified" per 269. 269 is written for the Utilities by the Utilities, the old chicken in the hen house syndrome. These poor operators have no idea as to what they are dealing with when racking switch gear breakers. As far as following both standards based on the line of demarcation (generation/general industry) that's unrealistic. It should be one standard for all, if in fact we are trying to save lives. My company has been in business for 60 years and we DO NOT have a Electrical Safety Program, I hope others are not in the same boat


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 Post subject: Re: OSHA 1910.269 vs NFPA 70E PPE Requirements
PostPosted: Wed Mar 08, 2017 10:10 am 
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generation safety adv wrote:
As a person who works in a Gen Station, it's nice to see a topic covering Generation. 269 leaves us in limbo because our hazards are in the box and the faults covered by 269 are open air. ...


Look again. "Open air" shows up in some of the exceptions only. See Appendix E for guidance on appropriate methods for dealing with three phase and arc in a box.

The scope of 269 leaves no doubt that generation is covered.


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 Post subject: Re: OSHA 1910.269 vs NFPA 70E PPE Requirements
PostPosted: Thu Mar 09, 2017 7:24 am 

Joined: Tue Sep 17, 2013 7:35 am
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Yes appendix E indicates it covers arc in the box, my problem was they were trying to use the IE tables that are for open air phase to ground to dictate PPE levels. They also fail to recognize that a tripped breaker is an indication of impending failure.


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 Post subject: Re: OSHA 1910.269 vs NFPA 70E PPE Requirements
PostPosted: Thu Mar 09, 2017 9:12 pm 
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generation safety adv wrote:
They also fail to recognize that a tripped breaker is an indication of impending failure.


That's one of the items that is missing from BOTH 70E and 1910.269 in the task tables.


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 Post subject: Re: OSHA 1910.269 vs NFPA 70E PPE Requirements
PostPosted: Thu Mar 09, 2017 10:03 pm 
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generation safety adv wrote:
As a person who works in a Gen Station, it's nice to see a topic covering Generation. 269 leaves us in limbo because our hazards are in the box and the faults covered by 269 are open air.


Actually 269 tables specifically say they are open air only. Arc "in a box" under IEEE 1584 empirical models is not quite what some people think. Below 1 kV the arcing fault calculation is different because box scenarios tend to reflect heat more (radiosity) which enhances arc restriking. Above 1 kV IEEE 1584 simply ignores arcing vs. bolted fault current and treats them identically because at that point there isn't supposed to be a significant difference. The second effect of "arc-in-a-box" is that the enclosure acts sort of like a lense/mirror and concentrates the incident energy somewhat. The major impact is that the exponent (rate of decay of incident energy with respect to distance) is less in an enclosure compared to open air.

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I would like to comment on Paul's remark that Generation is treated differently because everyone in Generation is "Qualified". I have been trying to explain this to management for over a decade. Let me tell you, close to nobody in our fleet is "Qualified" per 269. 269 is written for the Utilities by the Utilities, the old chicken in the hen house syndrome. These poor operators have no idea as to what they are dealing with when racking switch gear breakers. As far as following both standards based on the line of demarcation (generation/general industry) that's unrealistic. It should be one standard for all, if in fact we are trying to save lives. My company has been in business for 60 years and we DO NOT have a Electrical Safety Program, I hope others are not in the same boat


I can't comment on your particular situation but I can comment on training in general. I'm a field service contractor at this point. I have dozens of clients. I see all kinds, government, utility, industrial, maritime, and even the occasional construction site. I can honestly tell you I see all kinds and always have. The first mine I worked at had 1500 employees and...I'm not making this up, 750 recordables per year. The next one had an RIR of around 0.2 with about 250 employees so basically they had to go over a year without a recordable to keep it that low.

As to merged rules, you aren't already doing this? You are required to. Annex A under 269 explains it, and this is one section that the utilities didn't get to write...OSHA did. Essentially that section says that generation, transmission, and distribution gear follows 269. Utilization equipment even within a generating station such as say lights and controls follows Subchapter S. And if you have a mixed scenario such as a lighting panel that powers both a battery charger for protective relay power, and lighting, you apply BOTH Subchapter S and 269 regulations. In practice, it's not that bad. There are four major differences:
1. OSHA requires FR PPE everywhere under 269, even when the arc flash hazard is less than 1.2 cal/cm2. The working distance is also set to rubber glove energized method working distance (15") and the incident energy cutoff is raised to the threshold at 2 seconds (2.0 cal/cm2). There are specific rules for it under 269 whereas it's just the general duty clause under Subchapter S.
2. Terminology is different. There is no "limited approach boundary" although there are rules regarding what might as well be called the "public protection" boundary such as 10 feet from energized power lines. The restricted approach boundary is called the MAD although the distances are identical in terms of shock protection boundaries. This kind of makes sense because everyone is qualified.
3. The restriction on energized work is missing under 269 because the presumption is to always work energized or that it is impossible to actually remove power (induction, lightning, etc.). The work briefing is required under 269 but absent from Subchapter S.
4. LOTO is slightly different. You can have tags without locks under 269 at a central control room. Grounding is pretty much mandated. The lock removal procedure has more requirements. When you test for absence of voltage and when you ground are flip-flopped. It gets stranger still because if I recall correctly I counted no less than 4 different LOTO sections under 269 vs. 1 in Subchapter S, 1 in Subchapter J, and we might include 1 in Subchapter O.


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 Post subject: Re: OSHA 1910.269 vs NFPA 70E PPE Requirements
PostPosted: Thu Mar 16, 2017 7:15 am 

Joined: Tue Sep 17, 2013 7:35 am
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"As to merged rules, you aren't already doing this? You are required to." (Paul) My company hangs their hat on the NESC statement that says something to the effect that, anything owned by the utility within the fences of the utilities property is Generation. I can't seem to breakthrough, it doesn't help that its' only one person fighting the system. I don't even want to get into the LOTO in this forum. I did however convince them that the "System Operator" clause did not apply to our facility. Small victories`


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 Post subject: Re: OSHA 1910.269 vs NFPA 70E PPE Requirements
PostPosted: Thu Mar 16, 2017 10:20 am 
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[quote="generation safety adv"]"As to merged rules, you aren't already doing this? You are required to." (Paul) My company hangs their hat on the NESC statement that says something to the effect that, anything owned by the utility within the fences of the utilities property is Generation. I can't seem to breakthrough, it doesn't help that its' only one person fighting the system. I don't even want to get into the LOTO in this forum. I did however convince them that the "System Operator" clause did not apply to our facility. Small victories`[/quot

Constitution trumps statutes trumps regulations trumps standards trumps work rules, in that order.

OSHA recognizes NESC essentially as an engineering standard but differs in terms of regulation in a number of places. Here's a recent letter of interpretation on the subject:
https://www.osha.gov/pls/oshaweb/owadis ... p_id=29693

Appendix A covers exactly how to handle the "269 vs. Subpart S" differences: "This appendix presents information, in the form of flow charts, that illustrates the scope and application of § 1910.269. This appendix addresses the interface between § 1910.269 and Subpart S of this Part (Electrical), between § 1910.269 and § 1910.146 (Permit-required confined spaces), and between § 1910.269 and § 1910.147 (The control of hazardous energy (lockout/tagout)). These flow charts provide guidance for employers trying to implement the requirements of § 1910.269 in combination with other General Industry Standards contained in Part 1910. Employers should always consult the relevant standards, in conjunction with this appendix, to ensure compliance with all applicable requirements.".

Earlier in the scope section it makes it VERY clear that OSHA sees it as generation, transmission, and distribution ONLY. Everything else (utilization) even if it is within a utility, is utilization and covered under Subpart S:

"1910.269(a)(1)(i)(E)(2)

Paragraphs (a)(2), (a)(3), (b), (c), (g), (k), (p), and (r) of this section apply to line-clearance tree trimming covered by the introductory text to paragraph (a)(1)(i)(E) of this section when performed by line-clearance tree trimmers who are not qualified employees.
1910.269(a)(1)(ii)

Notwithstanding paragraph (a)(1)(i) of this section, §1910.269 of this part does not apply:
1910.269(a)(1)(ii)(A)

To construction work, as defined in §1910.12 of this part, except for line-clearance tree trimming and work involving electric power generation installations as specified in §1926.950(a)(3) of this chapter; or
1910.269(a)(1)(ii)(B)

To electrical installations, electrical safety-related work practices, or electrical maintenance considerations covered by subpart S of this part.
Note 1 to paragraph (a)(1)(ii)(B): The Occupational Safety and Health Administration considers work practices conforming to §§1910.332 through 1910.335 as complying with the electrical safety-related work-practice requirements of §1910.269 identified in Table 1 of appendix A-2 to this section, provided that employers are performing the work on a generation or distribution installation meeting §§1910.303 through 1910.308. This table also identifies provisions in §1910.269 that apply to work by qualified persons directly on, or associated with, installations of electric power generation, transmission, and distribution lines or equipment, regardless of compliance with §§1910.332 through 1910.335.

Note 2 to paragraph (a)(1)(ii)(B): The Occupational Safety and Health Administration considers work practices performed by qualified persons and conforming to §1910.269 as complying with §§1910.333(c) and 1910.335.

"
And yes, I realize it's a royal pain to deal with two jurisdictions but that's the regulation we have now. Unless the new administration changes it, that's how things will be going forward.


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