Arc Flash Blast Ducts/Ports Safety Barriers


United States
We've installed some arc-resistant gear outside at some of our utility plants and the equipment is surrounded by some non-resistant gear. Issue we're having is coming up with a way to mark off a safety boundary for where the "Arc Flash Duct Ports" are venting to. If you were to walk next to the arc-resistant gear you would be walking directly under the ports, and the plant currently has up temporary safety barriers by way of chains with signs that read "Hot Arc Flash Gas Exhaust Area" and they are looking for a more permanent solution.

I just inherited responsibility for the AF safety of these plants so I wasn't a part of the installation process and this is the first time I've seen ducts/ports that have been configured in a way so that they would vent into a pedestrian walkway. It's not a high-traffic area, but still a possible safety issue and a new issue for me. I understand what they're trying to accomplish from a safety perspective but how is this different from establishing an Arc Flash Boundary on a non arc-resistant piece of equipment? Meaning why would a safety barrier need to even be in place unless there was maintenance being done on the equipment where there would then be a threat of an arc-flash? If a safety barrier isn't necessary is there an IEEE or other reference stating this? My thinking is, when you have non-resistant gear and you are going to open a panel for example, then you need to wear appropriate PPE within the AFB, but not if you're just simply walking by, and I don't see why this is any different but we don't have much arc-resistant gear so I don't have a great deal of experience with it and I would assume the barriers are in place for a reason and I just don't know why yet. Thanks a lot as always....I get great insight from others here.


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