Arc Flash

Arc Flash 101

In my own terms an arc flash is an event that occurs during and electrical short circuit.  This consists of several components working together that can kill those involved in the flash area.  The flash occurs when something or someone creates a short circuit.  The term arcing is similar to a welder arc or maybe you have plugged in something at your home when something was wrong, you may hear a buzzing and see bright sparks or an arc of bright light occur.  An arc flash may occur at normal household voltage however, the severity of a second degree burn is not normally seen in residential wiring.  The arc flash voltages are usually greater then 240v A.C. and can cause second degree burns or death.  This is known as three phase voltages used for equipment in hospitals and industry.   Industry and hospitals may have workers exposed to voltage ranging from 240v - 15,000v A.C...

Now we have learned what creates the phenomena know as arc flash in this brief layman’s description.  Let explore it deeper. Everyone has their own description of the term ARC FLASH.

My description would be; An intense release of heat at or near a short circuit that can have temperatures as hot as the suns surface.  The light and resulting pressure wave can kill you alone. The arc ionizes the surrounding area and the air becomes conductive and travels inches to feet according to the about of electrical available to the next conductor and the energy grows in intensity.  The energy continues to disperse outwards from the origin at the speed of light and may last from hundreds of a second to seconds again depending on the available energy and protective device trip times.