Important: This calculator uses simplified IEEE 1584-2002 equations for estimation. A complete arc flash study by a qualified engineer is required for official arc flash labels and PPE selection.

Arc Flash Incident Energy

Estimate incident energy using IEEE 1584 simplified method.

Available fault current at equipment
Total clearing time (breaker + relay)
Typical: 18" panels, 24" switchgear
Typical: 32mm (480V), 104mm (4160V+)

Arc Flash PPE Categories (NFPA 70E Table 130.7(C)(15)(c))

Category Incident Energy Min Arc Rating Typical PPE
10-4 cal/cm24 cal/cm2Arc-rated shirt/pants, safety glasses, hearing protection
24-8 cal/cm28 cal/cm2Arc-rated coveralls, face shield, balaclava
38-25 cal/cm225 cal/cm2Arc flash suit hood, arc-rated jacket/pants
425-40 cal/cm240 cal/cm2Multilayer arc flash suit, full face hood
Danger>40 cal/cm2N/ADO NOT WORK - Reduce hazard before proceeding
Warning: Work on energized equipment with incident energy exceeding 40 cal/cm2 is prohibited. De-energize or implement engineering controls to reduce hazard.