Electrical arc flash is the unexpected release of energy in the form of light, heat, sound, and a blast of arc products that may consist of vaporized components of enclosure material (copper, steel, or aluminum). According to the National Fire Protection Association (NFPA) and the Institute of Electrical and Electronics Engineers (IEEE), 2,000 workers each year are admitted to burn centers for extended injury treatment caused by arc flash.
This NFPA video shows what happens during an electrical arc flash:
If necessary, a copy of the video transcript (PDF) is available.
NFPA standard 70E requires electrical equipment owners to perform arc flash hazard analysis to determine the arc flash boundary, the incident energy at the working distance, and the personal protective equipment (PPE) that workers within the arc flash boundary must use. PPE is not intended to prevent all injuries, but is intended to mitigate the impact of an arc flash, should one occur.
The university takes multiple precautions to avoid arc flash:
Arc flash analysis is a technical study investigating a worker’s potential exposure to arc flash energy. The study is prepared by an electrical engineer and conducted for the purposes of injury prevention and determination of safe work practices, arc flash boundary, and appropriate levels of personal protective equipment (PPE).
The arc flash analysis must be updated when a major modification or renovation takes place. It must be reviewed periodically, not to exceed five years, to account for changes in the electrical distribution system that could affect the results of the arc flash hazard analysis.
The arc flash hazard analysis and recommended PPE levels are no substitutes for safe work practices. Certain burn injuries can occur even when adequate PPE is employed, and the recommended PPE may provide little or no protection against arc blast and its effects when circuits or equipment have not been placed in an electrically safe work condition .
The Facilities Operations and Maintenance division of Facilities Services has been charged with developing an Arc Flash Analysis Program (AFAP) on behalf of the university. The program was established to develop the standard procedures for the implementing of and continuing compliance with the national and industry standards governing electrical safety.
The guidelines for work involving electrical hazards and the selection of arc flash protective equipment are provided by National Fire Protection Association (NFPA) standard 70E. This standard requires electrical equipment owners to perform arc flash hazard analysis to determine the arc flash boundary, the incident energy at the working distance, and the personal protective equipment (PPE) that employees within the arc flash boundary must use.
The arc flash analysis must be updated when a major modification or renovation takes place. It must be reviewed periodically, not to exceed five years, to account for changes in the electrical distribution systems that could affect the results of the arc flash hazard analysis.
Institute of Electrical and Electronics Engineers (IEEE) standard 1584 provides the standard for calculating arc flash energy levels at different points in the electrical power system.
Progress on Arc Flash Analysis on the university's Main Campus is detailed in a quarterly report, prepared by the AFAP team:
Arc Flash Report (PDF)
National Fire Protection Association (NFPA) standard 70E states that, when necessary, labels must be posted on special equipment to "warn employees about electrical hazards that might endanger them." In compliance with the standard, the university requires the following information for arc flash labels posted on identified equipment:
Here is an example:
View a flow chart (PDF) that illustrates the process for determining when project managers should incorporate arc flash analysis into the scope of projects at the university.
For questions or additional information about the university's Arc Flash Analysis Program, contact:
For questions or information regarding the university's facilities-related safety programs, contact: