Arc Fault Hazards

WARNING:
Arc Flashes or Arc Blast Hazards can occur while opening the door of the Electrical Disconnect Switch.
  • Arc Flash can occur if a conductive object gets too close to a high-amp current source or by equipment failure (for instance, opening or closing disconnects). The arc can heat the air to temperatures as high as 35,000° F, and vaporize metal in equipment. The arc flash can cause severe skin burns by direct heat exposure and by igniting clothing.
  • Electrical maintenance personnel should be fully trained in Arc Flash safety and protection procedures before attempting maintenance on electrical equipment.

Safe practices:

  • Never face a disconnect when placing it into the "OFF or ON" position. Turn your body away.
  • Always wear PPE (personal protective equipment)
  • Be aware of all warning labels and understand them fully before attempting to service
NFPA 70E Arc Flash Hazard Appropriate PPE Required Warning

The following National Electric Code (NEC) recommendations apply to arc flash labels:

  • 110.16 FLASH PROTECTION. Requires that switchboards, panel boards, industrial control panels, and motor control centers, excluding those used in dwelling occupancies, are required to have field marked labels warning qualified personnel of the arc flash hazards while in an energized state, and are likely to undergo examination, adjustment, servicing, or maintenance.
  • The NEC, through Fine Print Notes (FPN) also recognizes the National Fire Protection Agency, NFPA 70E, Electrical Safety Requirements for Employee Workplace, a NEC publication updated every three years, as a resource to provide assistance in adopting safe work practices, arc flash hazard analysis, explains the resulting protection zones and the arc flash label requirements as well as establishing the proper PPE (personal protective equipment) to be utilized.
  • In addition, the NEC FPN references ANSI Z535.4, Product Safety Signs and Labels, which specifies color, signal words, as well as other recommendations for the design of safety signs and labels to convey the information applied to products in a readable, consistent way.