We used to measure time by the sun and moon. Egyptians devised the first calendar with 365 days. Greeks named months after gods; Romans followed suit. From ancient observations to modern precision, humans have almost always needed to track progress in time. And yet, placing a date on an arc flash label can still cause confusion. (I bet you didn’t see that one coming.)
A common question I receive during my NFPA 70E and Arc Flash/IEEE 1584 classes is, “Is the date required to be on the arc flash (equipment) label?”
Two standards can provide insight to answer this question: NFPA 70E, Standard for Electrical Safety in the Workplace, and NFPA 70, National Electrical Code.
I added the word ‘equipment’ to arc flash label above because, although most refer to the term “arc flash” when discussing labels, including NEC 110.16, the term “equipment labeling” is used in NFPA 70E 130.5(H).
This section states: “The incident energy analysis shall be updated when changes occur in the electrical distribution system that could affect the results of the analysis. The incident energy analysis shall also be reviewed for accuracy at intervals not to exceed 5 years.”
This second sentence is generally interpreted as a requirement to review the study every 5 years and possibly revise it if necessary—including the labels. However, how do you know when the “5-year clock” begins?
A common response might be, “We start the clock based on the date of the study that is also listed on the label.”
However, did you know that NPFA 70E does not require a date on the label and the NEC only requires the date in specific instances? Let’s explore the details.
70E 130.5(H) equipment labels
This section begins with what equipment requires a label: “Electrical equipment such as switchboards, panelboards, industrial control panels, meter socket enclosures, and motor control centers, that are in other than dwelling units, and that are likely to require examination, adjustment, servicing, or maintenance while energized, shall be marked with a label containing all of the following information:
- Nominal system voltage
- Arc flash boundary
- At least one of the following:
- Available incident energy and the corresponding working distance, or the arc flash PPE category in Table 130.7(C)(15)(a) or Table 130.7(C)(15)(b) for the equipment but not both.
- Minimum arc rating of clothing
- Site-specific level of PPE”
The date is not mentioned anywhere in this language. Instead, including the date is left up to the owner or person performing the study.
NEC 110.16 arc flash hazard warning
NEC Section 110.16(A), General, contains language similar to NFPA 70E, stating, “Electrical equipment such as switchboards, switchgear, enclosed panelboards, industrial control panels, meter socket enclosures, and motor control centers, that is in other than dwelling units, and is likely to require examination, adjustment, servicing, or maintenance while energized, shall be field or factory marked to warn qualified persons of potential arc flash hazards.”
Once again, there is no mention of requiring a date. There is also nothing stated about specific details required for the arc flash hazard warning.
However, there is additional text in Section 110.16(B), Service Equipment and Feeder Supplied Equipment, below. This section contains the following language: “In other than dwelling units, in addition to the requirements in 110.16(A), a permanent arc flash label shall be field or factory applied to service equipment and feeder supplied equipment rated 1000 amperes or more. The arc flash label shall be in accordance with applicable industry practice and include the date the label was applied.”
Informational Note 2 of this section references NFPA 70E.
Finally, including the date on the label is mentioned—but only for service equipment and feeder supplied equipment rated 1,000A or more.
Although NFPA 70E does not require a date on equipment labels and the NEC only requires one on arc flash hazard warning labels for service equipment and feeder-supplied equipment rated 1,000A or more, many people often prefer to include a date to help them keep track of the 5-year review requirement.
Survey says…
Several years ago, I conducted a survey on my website ArcFlashForum.com to gauge opinions about requiring a date on the label. Although far from a scientific survey, 90% of respondents felt the date should be included, whether it is a requirement or not. Of course, the date should be based on the calendar, not the sun and moon.
Note: The views provided here are the author’s and do not necessarily reflect those of any particular standards organization.
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About The Author
PHILLIPS, P.E., is founder of brainfiller.com and provides training globally. He is Vice-Chair of IEEE 1584 Arc Flash Working Group, International Chair of IEC TC78 Live Working Standards and Technical Committee Member of NFPA 70E. He can be reached at [email protected].
