Video Information 3

[ruggedscot]

http://www.liveleak.com/view?i=995_1213752982

This is quite a video - found it while looking up information on arc flash. Id really appreciate knowing more about this as in if the guy survived and what exactly happened. To me it looked like a possible racking fault maybe racking out a breaker that was still in the closed position or trying to rack it back in while load was connected. All in all quite a scary video and one that I think that is worth seeing. If only to make a timely reminder that this is dangerous work.

Rugged

 

[Zogzog]

Wow! Anyone know ant details about this one? This video will be making the rounds like the one in 2001 from the plant in WI that had the arc flash caught on the security camera.

Just another reason for remote racking.

 

[dpc]

RuggedScot,

Thanks for the link. I notice the guy put his hearing protection on, but no face shield for arc-flash. It's look they might be wearing FR shirt and pants - it's hard to tell.

If anyone knows the outcome, let us know.

 

[itsmoked]

Wow.. Nasty. Would that be MV or LV?

He is cranking the crank clockwise if that sez racking IN?


Where is that other arc flash 2001 you speak of Zogzog?

Keith Cress
kcress -

http://www.flaminsystems.com

 

[ScottyUK]

I need to show this to someone who was arguing that racking a breaker on or off the bar is not 'live work'. It's a pity that it takes a video clip of something like this to do the convincing - thanks for providing the link.

Hope the guys involved were ok - looks like a big blast to be caught up in.


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If we learn from our mistakes I'm getting a great education!

 

[Zogzog]

I cant ID this gear for North Amercia stuff, and I am pretty sure this is european stuff, any friends across the pond ID this gear? To me it looks like LV switchgear, just based on the way ot os laid out.

itsmoked, here is the one I was talking about

http://uk.youtube.com/watch?v=h10ALIpD0R4

I did a training class 2 years ago and the OSHA inspector that investigated this accident was in my class if you want details.

 

[itsmoked]

Thank you Zogzog. It appears the guy didn't suffer serious injury. Which is great. Looks like he may have gotten an attitude adjustment though.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[ScottyUK]

Agree it looks like big LV stuff, but don't recognise it as being anything from our patch. It's a bad angle to judge from. It seems very deep for an LV board - dry transformer somewhere in the rear section maybe?

One question I'm nearly always asked when I show these video clips is 'What category arc was that?', to which I usually shrug and mutter 'a bloody great big one'. Anyone care to take an educated guess on the first clip?


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If we learn from our mistakes I'm getting a great education!

 

[alehman]

Also good justification for code required working space.

 

[Zogzog]

Not much really, I would say 10 cal/cm2 based on the tests I have observed.

 

[ScottyUK]

Thanks Zogzog. That's going to scare a few people who are talking about the times we need to work on (e.g.) a live 170cal/cm² board. My message to them is that there are no circumstances when I'll be working on anything with that energy level while it is energised, but some don't like the message.



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If we learn from our mistakes I'm getting a great education!

 

[Zogzog]

Go here

http://www.westexinc.com/

Click on Video library and watch the no manikin videos first, start with the 4 cal/cm2 arc flash. When we are used to dealing with higher Ei's 4cal/cm2 dosent seem like much, you will change your mind after this clip.

Then go on to watch the top 10, you can see the Ei's and specs for each one. If you think that an arc always comes straight out of the box these will change your thinking on that also. I was at this lab observing some testing last year, much more scary in person.

 

[tem1234]

Thank ruggedscot, it's the best video i saw, even if you don't want to see this

Zogzog, i would like to have info on the video that you post. i heard that he was seriously injured, after the adrenaline rush, he falled into a coma, but maybe i'm confused between 2 video. And you was there for the arc flash testing... you're lucky!!!

 

[Zogzog]

All 3 guys suffered severe burns, the one guy who was on his knees at the start of the video was induced into a coma for a few months to help him survive the procedures that needed to be done on him. All 3 survived but will never be the same.

Here are some more details on the video

http://www.mikeholt.com/files/PDF/NFPA review of the incident by Ken Mastrullo.pdf

 

[Zogzog]

Also if you look closely when he pulls his hard hat off you see something strech between the hard hat and his head, that was a nylon hairnet (Required at this food processing facility) and some of his scalp.

 

[davidbeach]

Nylon can not, must not, be worn. You can't even get to PPE level 1 with any nylon on the person.

 

[Zogzog]

Yep. that has actually been an OSHA rule since 1981. No nylon, rayon, polyester, etc....and the video shows why.

There are now FR hairnets on the market.

 

[tem1234]

Thanks Zogzog, pretty interresting and scary!

For the OP video, it's incredible how much the arc duration seem to be huge, maybe 3-4 seconds. I think that differential protection could help to reduce the arc duration and by the way incident energy, but it seems to be ignored by AFH analysis. Do you ever considerate a differential protection in a AFH study?

 

[dpc]

Differential protection can drastically reduce arc-flash levels. Buses protected by only overcurrent relaying have very slow clearing times since the bus overcurrent relays must be set slower than the slowest feeder and possibly the tie.

 

[itsmoked]

Zogzog; Great stuff. Important! Many thanks for the links. I can use them to good effect.

Keith Cress
kcress -

http://www.flaminsystems.com