An instrument used to determine the safe distance from exposed energized electrical conductors or circuit parts is essential for worker safety. It calculates the distance at which an unprotected person would begin to sustain a curable second-degree burn if an electrical arc flash were to occur. This calculation relies on factors such as system voltage, available fault current, and clearing time of overcurrent protection devices. The outcome, typically expressed in feet or meters, establishes a safety perimeter around the potential hazard.
Adherence to safety standards and regulations mandates the use of these calculations to mitigate the risks associated with electrical work. They aid in the selection of appropriate personal protective equipment (PPE) and the implementation of safe work practices. Historically, these calculations were performed manually using complex formulas. Now, software and online tools greatly simplify the process, allowing for more efficient and accurate assessment of potential hazards, ultimately leading to a reduction in workplace injuries and fatalities.