In the 2018 NFPA 70E (Standard for Electrical Safety in the Workplace), section 130.5(F) allows two options for selecting the proper level of PPE:
(1) The incident energy analysis method in accordance with 130.5(G)
(2) The arc flash PPE category method in accordance with 130.7(C)(15)
Either, but not both, methods shall be permitted to be used on the same piece of equipment. The results of an incident energy analysis to specify an arc flash PPE category in Table 130.7(C)(15)(c) shall not be permitted.
As mentioned above, 130.7(C)(15) can be used instead of performing an incident energy analysis. Table 130.7(C)(15)(a) is used to determine the arc-flash PPE category and the arc-flash boundary. (See image)
In order to even begin to use this table, the qualified person must already know several key pieces of information:
If any one of the above are not known, then Table 130.7(C)(15)(a) cannot be used and an incident energy analysis must be performed instead of using the Table.
Refer to NFPA 70E Table 130.7(C)(15)(a) in the image to answer the following question:
Which of the following is true when working on a 120/208V panelboard while energized? The panelboard has 25 kA of available fault current, an overcurrent device with a max clearing time of 2 cycles and 18 inches is needed for a safe working distance.
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