I added the word (equipment) to arc flash label above because although most refer to the term “arc flash” when discussing labels including the National Electrical Code 110.16, the term “Equipment Labeling” is used in NFPA 70E 130.5(H).

NFPA 70E Standard for Electrical Safety in the Workplace

NFPA 70E 130.5(G) Incident Energy Analysis Method.

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.”

This section also states:

“The incident energy analysis shall also be reviewed for accuracy at intervals not to exceed 5 years.”

This second line is generally interpreted as a need 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 National Electrical Code only requires the date in specific instances? Let’s explore the details.

NFPA 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:

1) Nominal system voltage

2) Arc Flash Boundary

3) 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. (I discuss the history of how “not both” was added to the 2009 edition during my NFPA 70E training class.)

Minimum arc rating of clothing

Site-specific level of PPE

In the above language, adding a date is not mentioned.

Requiring the date has come up during the NFPA 70E revision cycle and each time, including the date is left up to the owner or person performing the study.

National Electrical Code

NEC 110.16 Arc-Flash Hazard Warning
(A) General.
This section of the NEC 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 110.16(B) below.

NEC 110.16 Arc-Flash Hazard Warning
(B) Service Equipment and Feeder Supplied Equipment

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 1000 amperes or more.  

Although NFPA 70E does not require a date on equipment labels and the NEC only requires a date on arc flash hazard warning labels for service equipment and feeder supplied equipment rated 1000 amperes or more, many people prefer to include a date as a way to keep track of the five year review requirement.

And the Survey Says…

Several years ago, I conducted a survey at my website ArcFlashForum.com to gauge the thoughts about requiring a date on the label.  Although far from a scientific survey, and conducted several years ago, 90 percent of the respondents felt the label should be included on the label whether it is a requirement or not. 

Note: The views provided here are the author’s and not from any particular standards organization.