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 Post subject: Work permit for 120V circuits?
PostPosted: Thu Apr 11, 2013 9:46 am 

Joined: Wed Dec 21, 2011 3:20 pm
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Location: NV
We have hundreds of 120V panels that are category 0; less than 1.2 cal/cm2. Occasionally, electricians remove the front covers to R&R breakers or pull in new circuits with the panel energized, . All electricians wear arc rated PPE as their daily apparel but, we have been doing the work without using an "Energized Work Permit". I'd like some input from others on whether or not this is a correct interpretation of NFPA70E? We do use "Energized Work Permits" when doing scheduled work on energized panels, if they are above 1.2cal/cm2. The assumption of personnel here is that since it is Cat 0 the "Energized Work Permit" doesn't apply but, I haven't found anything confirming that in the NFPA70E.


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PostPosted: Mon Apr 15, 2013 6:31 am 

Joined: Wed Jan 26, 2011 12:04 pm
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daveelko wrote:
We have hundreds of 120V panels that are category 0; less than 1.2 cal/cm2. Occasionally, electricians remove the front covers to R&R breakers or pull in new circuits with the panel energized, . All electricians wear arc rated PPE as their daily apparel but, we have been doing the work without using an "Energized Work Permit". I'd like some input from others on whether or not this is a correct interpretation of NFPA70E? We do use "Energized Work Permits" when doing scheduled work on energized panels, if they are above 1.2cal/cm2. The assumption of personnel here is that since it is Cat 0 the "Energized Work Permit" doesn't apply but, I haven't found anything confirming that in the NFPA70E.

Before discussing the permit issue, it seems like the underlying premise at your shop is that the 120V panels can't be de-energized. While I see this type of task all the time and understand your challenge, particularly if it involves lighting or ventilation, it's actually a problematic premise on which to base the energized work. The systems lost if you de-energize should have a degree of criticality that isn't judged as inconvenience but something more significant. But forgive me for what might sound like an admonition. I just wanted to preface my next point on permits with the point above.
If you must work the panel energized, then I still think you would need to use a permit. Exceptions to using a permit are limited to testing, troubleshooting, and voltage measuring (NFPA 70E-2012 130.2(B)(3). We've taken it a bit further and have some production bench testing (hi-pot/insulation) included, but I don't think pulling new wiring into a 120V panel comes into the same category. It might be more palatable for the electricians if a single permit is written for the shift, but even that permit would need to analyze the risk of each panel, including traffic nearby and all the other shock and flash hazard analyses.


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PostPosted: Mon Apr 15, 2013 10:11 am 

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twm22 wrote:
Before discussing the permit issue, it seems like the underlying premise at your shop is that the 120V panels can't be de-energized. While I see this type of task all the time and understand your challenge, particularly if it involves lighting or ventilation, it's actually a problematic premise on which to base the energized work. The systems lost if you de-energize should have a degree of criticality that isn't judged as inconvenience but something more significant. But forgive me for what might sound like an admonition. I just wanted to preface my next point on permits with the point above.
If you must work the panel energized, then I still think you would need to use a permit. Exceptions to using a permit are limited to testing, troubleshooting, and voltage measuring (NFPA 70E-2012 130.2(B)(3). We've taken it a bit further and have some production bench testing (hi-pot/insulation) included, but I don't think pulling new wiring into a 120V panel comes into the same category. It might be more palatable for the electricians if a single permit is written for the shift, but even that permit would need to analyze the risk of each panel, including traffic nearby and all the other shock and flash hazard analyses.

Concur with twm22's premise. I also recommend reviewing the circuits/funcitons of these 120V panels feed. It is difficult to believe that all 100 control panels fall into the catagories of "additonal hazards", "increased risk" or "infeasible". Possible schedueling the work on a off shift or a weekend? The initial question focused on arc flash hazard being low, HRC 0, which is no surprise for 120V circuits. However there is still a shock hazard to contend with when doing CB replacement and pulling wire. It is certainly a culture change to denergize 120V circuits for these tasks that historcially have been performed energized. Completing an energized work permit and really focus on the justification may be enlightening. The NFPA 70E Handbook has a good discussion on "infeasible" vs. "inconcenient".


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PostPosted: Mon Apr 15, 2013 10:25 am 
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Location: Michigan
The Energized Electrical Work Permit is not just for arc flash hazards, but shock hazards too (which are much more prevalent).

Our company interprets EEWP as being required for work over 50V. Testing, troubleshooting or visual inspection is not classified as work, but installing or removing components or conductors is. Basically we get everything prepped, then shut stuff off during lunches or shift changes; if it’s going to take longer we schedule an outage for the weekend (sometimes it's tough).

70E says an EEWP is required when working within the limited approach or arc flash boundary of exposed energized parts that have not been placed in an electrically safe work condition [that is, for the reason of increased hazard or infeasibility per 130.2A] work to be performed shall be performed by written permit only.

Energized work is only permitted if the employer can demonstrate greater hazard, infeasibility or it is less than 50V. So if you meet one of the exceptions listed in 130.2(A)(1-2) you still need a permit per 130.2(B)(1).


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PostPosted: Mon Apr 15, 2013 3:39 pm 
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Look on OSHA's web site under the regulation (1910.333) as they have several letters of interpretation that clearly describe what is justifiable energized work and what is not. I know the fine print refers to lighting and ventilation but that is pretty clearly not the way that OSHA is interpreting it. Is there a greater hazard in tripping a breaker and establishing a safe working condition (deenergizing) or working with live wiring where one mistake can lead to a shock or an arc flash even if it is nonfatal?

This is symptomatic of the approach of using PPE as the first resort to mitigating hazards instead of the last.


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PostPosted: Tue Apr 16, 2013 4:28 am 
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My 3 cents... it probably isn't a 120V panel... probably 240/120 or 208/120... just a pet peeve.

Now, while I like the EEWP, and recommend its use, OSHA does not require it. It is amazing how a manager's attitude toward energized work changes when he/she has to sign the dotted line requesting energized work AND why it cannot be taken to an electrically safe work condition. As PaulEng stated, energized work must be justified as:

1 - Diagnostics/troubleshooting
2 - Increased or additional hazards
3 - Infeasible to equipment design or operational limitations

So, if a person is working in the panelboard as you suggested and gets electrocuted, it's pretty easy to play Monday morning armchair quarterback. Here are the questions that you will have to answer:

1 - Why was the system energized? Diagnostics, increased hazards, or infeasibility MUST be demonstrated (shown).
2 - What PPE was the employee wearing? Shock AND arc flash
3 - What tools were the employee using? Voltage rated and insulated?
4 - What training had the employee received? Documented and qualified?

The resulting citations will be based on OSHA 29CFR1910 Subpart S, and possibly 29CFR 1910.132. The most common citations I have seen have been for failing to deenergize, failing to train, and failing to provide the appropriate PPE. There will not be a citation for lack of an EEWP.


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PostPosted: Wed Apr 17, 2013 5:06 pm 

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viper57 wrote:
Now, while I like the EEWP, and recommend its use, OSHA does not require it.

The resulting citations will be based on OSHA 29CFR1910 Subpart S, and possibly 29CFR 1910.132. The most common citations I have seen have been for failing to deenergize, failing to train, and failing to provide the appropriate PPE. There will not be a citation for lack of an EEWP.



Viper makes a good point. The permit is not required. It's easy to lose sight of that fact. That being said, it seems like a difficult task to organize all the OSHA requirements without a framework, so the permit serves as the right vehicle for us


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PostPosted: Thu Apr 18, 2013 7:43 am 

Joined: Wed Dec 21, 2011 3:20 pm
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Location: NV
Thanks for the replies, for clarification I originally stated "Occasionally, electricians remove the front covers to R&R breakers or pull in new circuits with the panel energized," we do de-energize the panels whenever feasible. But, this is a mine (governed by MSHA not OSHA) that operates 24 hrs a day and some of the panels are powering cyanide & pH monitors(personnel safety), control valves, flow meters (environmental spills). All employees have received NFPA70E and NEC training and use voltage rated tools. For the CYA factor we will probably begin using Work Permits for energized 120V work; just wanted to hear what other facilities are doing. Viper -Most panels are actually 208/120V, I was just trying to be brief; if I were to put in all the details this would be 2 pgs long.


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PostPosted: Sat Apr 20, 2013 6:26 am 
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daveelko... it looks to me like you've got things under control. I was under MSHA jurisdiction for many years... totally different than OSHA! Good Luck!


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PostPosted: Sun Apr 21, 2013 5:09 am 
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EEWP is required. See 1910.333. First few paragraphs are for energized work. This was all adopted from an early (pre 2000) edition of 70E, before arc flash requirements. The language is similar to 2009 edition.


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PostPosted: Mon Apr 22, 2013 6:02 am 

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PaulEngr wrote:
EEWP is required. See 1910.333. First few paragraphs are for energized work. This was all adopted from an early (pre 2000) edition of 70E, before arc flash requirements. The language is similar to 2009 edition.

PaulEngr,
I disagree with PaulEngr but would appreciate his and others' feedback. My reasoning below comes from a cover-your-a$s perspective but unfortunately, it's the situation I'm often in.

Semantics come into play for me in that some of my stakeholders employ paperless or even system-less approaches. They would say that a permit system is not required (much to my dismay), and although we work toward documentation via a permit system, there are many that are taking all the steps (or attest to taking all the steps) required in 1910.333 without a formal permit system. The code in 1910.333 states "If the exposed live parts are not deenergized...other safety-related work practices [emphasis added by me] shall be used to protect employees who may be exposed to the electrical hazards involved.Such work practices shall protect employees against contact with energized circuit parts directly with any part of their body or indirectly through some other conductive object. The work practices that are used shall be suitable for the conditions under which the work is to be performed and for the voltage level of the exposed electric conductors or circuit parts."

Some of the shops with whom I work employ suchpractices but no formal permit system or even any documentation. In most cases, they execute the safe work practices; in other cases, they cannot prove that they do (hence one of the needs a permit system, in my mind).

I'm fully committed to the permit system approach, but sometimes can force the issue only so far. I would appreciate your thoughts (and any others) on this. Semantics - yes, but think diverse groups of electrical shops, large and small, some much less progressive than others, some with no real systematic culture of documentation or even quality.

In short, my disagreement is with the statement that a permit system is required. Imagine sitting around a table with personnel who are asking, "What must I do, legally?"


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PostPosted: Mon Apr 22, 2013 7:41 am 

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My two [color=black][font=Arial]₵, OSHA looks to industry standards for compliance. NFPA 70E being one of them (which I assume most people use for ES), does require an EEWP. If you are not going to use the guidelines of 70E, at a minimum, you must perform a hazard/risk assessment. Failure to do so may result in a citation under 1910.132. [/font][/color]


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PostPosted: Fri Apr 26, 2013 4:48 pm 
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I stand corrected partly.

An employer still has to demonstrate why the energized work is justified. The reasons are infeasibility, under 50 volts, and greater hazard. A letter of interpretation makes the case that production less is not enough. So somewhere along the line the employer has to demonstrate one of these and it would be best if it is in writing, and that there is some evidence of a management decision being made. I see no reason a formal risk assessment can't address this which would eliminate the need for an EEWP for routine, documented tasks.


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PostPosted: Thu May 02, 2013 9:57 am 
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daveelko wrote:
some of the panels are powering cyanide & pH monitors(personnel safety), control valves, flow meters (environmental spills).

I think that is sufficient justification for live work.

While you might be able to reasonably justify eliminating the need for an EEWP, I would think it would be better to use it anyway.


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PostPosted: Mon May 06, 2013 7:59 am 

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We are shifting to the any live work (not troubleshooting) performed inside the limited approach boundary of a system above 50V requires an EEWP. Though I like PaulEngr's formal risk assessment approach for routine tasks. It deviates from 70E, but seems defendable.

With the EEWP requirement, everything moves into the do it later when we can deenergize it planning bucket. It is challenging to to keep up with the back log of work.

Noone has mentioned the "removal of illumination" as a reason for performing energized work.

1910.333(a)(1)
Note 1: Examples of increased or additional hazards include interruption of life support equipment, deactivation of emergency alarm systems, shutdown of hazardous location ventilation equipment, or removal of illumination for an area.

Seems like Note 1 would allow changing of light ballasts with an EEWP instead of deenergizing the light circuit.

Anyone have a standing risk approach for light work or conduct this type of work under an EEWP?


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