What is an Arc Flash?
• An Arc Flash is an electrical fault (or short) between two electrical conductors – phase to phase, phase to earth, or phase to neutral. This energy release (flash) can be as minor as a flash of light with a popping sound, or as major as a fireball explosion with heat four times that of the sun, also known as an Arc Blast. The concern is that energy released above a certain level will ignite non-flammable clothing and cause major flesh burns • Fuses and breakers can let more that their rated currents through for a period of time until they open (or blow). Think about 15,000 amps dead shorted for a half a second – the result is a big flash of fire for that half a second, and that is an arc flash. • Over 70% of Electrical Arc Flash incidents occur during or immediately after electrical maintenance.
