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| PPE on Dead Bus https://brainfiller.com/arcflashforum/viewtopic.php?f=5&t=210 |
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| Author: | hydropwrbb [ Wed Sep 17, 2008 6:32 am ] |
| Post subject: | PPE on Dead Bus |
On a 13.8 KV switchgear that is a level 4 rating. If the bus voltage was deenergized through switching and verified with open breakers, would there still need to be AF level 4 clothing worn to rack out the 13.8 KV breaker? |
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| Author: | Zog [ Wed Sep 17, 2008 10:43 am ] |
| Post subject: | |
hydropwrbb wrote: On a 13.8 KV switchgear that is a level 4 rating. If the bus voltage was deenergized through switching and verified with open breakers, would there still need to be AF level 4 clothing worn to rack out the 13.8 KV breaker?
Yes, until you have done a voltage (live-dead-live) test and applied protective grounds 13.8kV switchgear is still treated as energized. See Article 120 in NFPA 70E or OSHA 1910.269. Another alternative is to rack the breaker from outside the arc flash boundary http://www.remoterackingsolutions.com |
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| Author: | hydropwrbb [ Wed Sep 17, 2008 11:14 am ] |
| Post subject: | |
Thanks very much. I had reviewed Art. 210 but met some opposition from craft on level of exposure. If I understand it right, until we are grounded after verification of being dead, we use the same level of protection that would be required as if it was live. |
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| Author: | Zog [ Wed Sep 17, 2008 12:53 pm ] |
| Post subject: | |
hydropwrbb wrote: Thanks very much. I had reviewed Art. 210 but met some opposition from craft on level of exposure. If I understand it right, until we are grounded after verification of being dead, we use the same level of protection that would be required as if it was live.
You are correct, and you should be wearing the same PPE to verify it is dead and to install grounds. I know, I know, chances are about 99% that it is dead when the breakers are open, but I have seen that other 1% happen, there are several things that can go wrong and ot still be energized. It only takes 1 time, If your crew needs some convincing, get "The Mark Standifer story" , arc flash victim on 13.8kV, 13.8kV switch, 1 phase didnt open, he didnt check it dead and nearly died because of that failed phase on the switch that didnt open, you can get it from ERI safety videos. |
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| Author: | geh7752 [ Thu Oct 16, 2008 5:23 am ] |
| Post subject: | |
I've also seen situations where a bus being back fed from another source due to a defective tie breaker. Always test before you touch.... |
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