The 2012 Edition of NFPA 70E, the Standard for Electrical Safety
in the Workplace, has made a significant change to the
information requirements for arc flash warning labels. According
to Section 130.5(C), the following is now required: “(1) Only
one of the following: “a. Available incident energy “b. Minimum
arc rating of clothing “(2) Date of arc flash hazard analysis
“(3) Nominal system voltage “(4) Arc flash boundary” The last
three items are straightforward. However, the first item has two
possible options—incident energy or arc rating. Which is the
better option? According to this section, either is acceptable,
but one of the options may have a distinct advantage over the
other. Option A—Available incident energy Listing the available
incident energy on the label is a very common practice. Most arc
flash calculation software automatically includes this value,
based on the calculated incident energy at a specific piece of
equipment, seemingly making option A the logical choice.
However, NFPA 130.5 requir