To Label or Not to Label: Common Questions About Arc Flash Labels
Q: Who is responsible for equipment labeling?
At times there has been some confusion as to who is actually the responsible party, with owners believing it was up to the electrical contractor to make sure the equipment was labeled, and vice versa. The NFPA 70E clarifies that the party accountable for installing and maintaining field-marked labels for electrical equipment is the owner of the equipment.
“The owner of the electrical equipment shall be responsible for the documentation, installation, and maintenance of the marked label.” NFPA 70E 130.5 (H) Equipment Labeling
Q: What Equipment Needs Arc Flash Labels?
You’ve ordered an arc flash study for your facility. You know that arc flash labels are to warn electrical workers and maintenance personnel about potential arc flash hazards in electrical equipment, but do you know what items of electrical equipment need arc flash labels? Here’s a hint; not all electrical equipment requires an arc flash label. Items that should have arc flash warning labels are: Switchboards, Panelboards, Distribution Boards, Industrial Control Panels, Enclosed Circuit Breakers, Motor Control Centers, Disconnects, Safety Switches (fused), Inverters, UPS’s, CT Cabinets, Transformers, External Variable Frequency Drives, TVSS’s (External), and SPD’s (External). Items that do NOT require arc flash warning labels are: Disconnects (unfused), Safety Switches (unfused), Motors, Internal Meters, Lighting Control Panels, TVSS’s (Internal), SPD’s (Internal), and Meter Control Sockets (Residential/Dwelling Unit). This list is not exhaustive and the NFPA 70E states that any electrical equipment likely to require examination, adjustment, servicing, or maintenance while energized requires an arc flash label.
Q: What information is required to be on an Arc Flash Label?
The NFPA 70E states that equipment must be labeled with 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
Minimum arc rating of clothing
Site-Specific level of PPE
Sample Arc Flash Label by PowerStudies
Q: Where should the labels be placed on the equipment?
The labels need to be placed on the outside front cover of the equipment. However, when it comes to panelboards, it is acceptable to place the labels on the inside of the door. They need to be clearly visible to any person who will be working on the piece of equipment while it is energized. Also, there are some instances where you will have line side and load labels for one piece of equipment. See next question for further details.
Q: Why do I have two labels for some equipment?
This typically occurs when there is a label for both the line side and load side of the equipment. This will be noted on the arc flash labels provided by PowerStudies. Both of these labels need to be applied to their respective line and load side locations on the equipment.
Example of Bus Side Label
Example of Line Side of a Protective Device
Q: How often do I need an updated Arc Flash study and labels?
Whenever new equipment or changes are made to the electrical system, the labels need to be updated. If no updates are made, the system should be reviewed for accuracy every 5 years. If the review finds any changes, the label and study are then inaccurate and need to be updated.
Click here to find more resources about Arc Flash!
Needing an Arc Flash study and labels? Request a quote!