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 Post subject: Need for an Arc Flash Study
PostPosted: Mon Aug 17, 2015 12:43 pm 
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Joined: Mon May 21, 2012 5:00 pm
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We have a client who believes they do not need to have an arc flash assessment performed (and no labels) at his site because they do no "hot" work, only de-energized. I would like to know your thoughts and how best to respond.


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 Post subject: Re: Need for an Arc Flash Study
PostPosted: Tue Aug 18, 2015 4:32 am 
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Location: Port Huron, Michigan
They can't know for sure that equipment is de-energized without testing. You can't easily test without putting yourself in a situation where you need to protect yourself from an arc flash.


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 Post subject: Re: Need for an Arc Flash Study
PostPosted: Tue Aug 18, 2015 7:58 am 
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Location: Rutland, VT
To determine the equipment is de-energized, you need to test it. Until it is tested, it must be considered live and all needed PPE is required.

For example: in a fused disconnect switch, it is believed that a fuse has blown. The switch handle is moved to the off or open position. Now since it hasn't been tested dead, it must still be considered live. Therefore, just to open the switch door, one needs the required PPE. This PPE would be needed to test dead also.

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www.workplacesafetysolutions.com


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 Post subject: Re: Need for an Arc Flash Study
PostPosted: Tue Aug 18, 2015 8:10 am 
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When I was writing my post, I was thinking about the possibility of non-contact methods of testing, and whether those could be considered to be "good enough". I was thinking about voltage indication and voltage ports put out by Graceport.

I am in agreement with you however, you can't really prove something is dead without testing, and to test you need to have the proper level arc flash PPE, meaning you have to have done an arc flash study, or at least done enough of a study to properly apply the tables.


wbd wrote:
To determine the equipment is de-energized, you need to test it. Until it is tested, it must be considered live and all needed PPE is required.

For example: in a fused disconnect switch, it is believed that a fuse has blown. The switch handle is moved to the off or open position. Now since it hasn't been tested dead, it must still be considered live. Therefore, just to open the switch door, one needs the required PPE. This PPE would be needed to test dead also.


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 Post subject: Re: Need for an Arc Flash Study
PostPosted: Wed Aug 19, 2015 6:28 pm 
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Location: North Carolina
Grace has been pushing this idea but it doesn't hold water with OSHA or NFPA 70E. They admit that their non-contact sensors are at best a supplemental system. The biggest value is for non-electrical workers for lockout as a way of verifying non-operation of equipment in cases where it is difficult at best to "try" to start it due to interlocks, etc.

The IEC standards for testing have 4 different methods for testing:
1. Phase lights or various electrical field measurement devices that are permanently mounted in switchgear, such as the ABB Visivolt.
2. Portable noncontact capacitive voltage field detection devices. Only for 1 kV or higher on AC.
3. Resistive portable voltage testing devices for 1 kV or higher, both AC and DC versions.
4. A voltmeter which makes direct, physical contact. Only for under 1 kV.

The IEC standards give specific thresholds that the meter must work within to indicator presence or absence of voltage.

I constantly see lots of people wanting to use noncontact meters below 1 kV, which is not supported by any standard. Similarly, I see the "480 V crowd) completely missing it and thinking that the one and only one way to test for absence of voltage is with a multimeter, even to the point of mixing methods.

In the case of the latter, there is a video done by a Georgia Pacific plant in Elkin, NC, which is hands down one of the best arc flash videos I've seen for the emotional "attention getter" videos. You can easily find it on Youtube.


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 Post subject: Re: Need for an Arc Flash Study
PostPosted: Mon Aug 24, 2015 6:44 am 
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The previous posts focus on the safety aspect of the question. However, it seems to me this company is really asking "do we have to spend the money on something we don't really need?" Further, you could get push-back similar to this” "our vendors are supposed to know this and besides, if one of their employees is injured, it’s not our problem." I wonder if you jump to 50,000 feet and looked at the company's other behaviors, you might see they're not really focused on safety, but only doing what's absolutely necessary.

My question is how are they maintaining their facility and it’s equipment now? Do you see maintenance practices that look marginal? Is their safety program (if they even have one) just for "looks" rather than to protect its workers? Do they have a culture of "it's working, so why bother shutting if off to maintain it?"

If that's what you’re seeing (or if it’s just a feeling), you’re probably wasting your efforts pushing an arc flash study. And to answer your question, yes, I agree, they need a study.

Good luck,


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 Post subject: Re: Need for an Arc Flash Study
PostPosted: Wed Aug 26, 2015 7:19 pm 
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A major international automotive components manufacturing company has the "no energized work" rule. This is enforced at ANY voltage (no 50 V cutoff). When I heard that a week or so ago, I asked a series of questions:
1. So if open up an MCC bucket after opening the disconnect, can I just start working on it once I lock out the disconnect? Answer: No. Must test for voltage first.
2. So after testing for absence of voltage, it's OK to start work as long as I stay away from the top of the breaker? Answer: Yes.
3. So is testing for absence of voltage energized work? Answer: Yes.
4. So, do you allow ANY electrical equipment in the entire plant to be worked on, since you can't do any energized work? Answer: Well, yes...
5. Can I plug my laptop in even though the plug is 120 V?
6. Can I plug in an Ethernet cable, since it can be up to 48 V?
7. Can I operate a push button on an operator console since it is switching 24 V?
8. How exactly do you change the battery on golf carts that the safety department uses since a battery is never truly "dead"?

I've almost memorized this list of questions simply because this same argument of simply banning energized work outright comes up time and again.


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