Arc Flash Effects: A Comprehensive Review

The electrical breakdown of a gas occurs when the voltage gradient applied is more than the standard voltage prescribed resulting in electric arc formation and subsequent electrical discharge of a gas (arc discharge) producing visible light called “arc” which glows intensely. This paper reviews Arcing effects and terms related to Arc such as Arc Flash and Arc Blast. As per National Fire Protection Association (NFPA) 70E standards, arc flash hazards which are categorised into 5 hazard risk categories and the amount of incident energy released during an arc flash event is analysed under Arc Flash Metrics. The amount of intense light released during the arc discharge and sound effects which affect the personnel are discussed here. The arc flash calculations referred to as Fuse and Circuit Breaker are reviewed with reference to the flash protection boundary and the clearing time required for these equipment and Personnel Protective Equipment (PPE) required for different hazard risk categories is considered with examples and results are comprehended.