Arc Flash

An arc flash is an explosive release of energy caused by an electrical fault that travels through the air between conductors or from a conductor to ground. In a data center it typically occurs inside switchgear, a power distribution unit or a busway, and the arc can reach temperatures of about 19,400 °C, hot enough to vaporize metal and injure anyone nearby. Beyond the human risk, a single event can trip an entire power path and, if cooling shares that path, force operators to shut equipment down to avoid thermal damage; Google Cloud attributed a 2024 Frankfurt zone outage to an arc flash in a power distribution unit. Hazard levels are calculated under IEEE 1584 and managed through NFPA 70E practices, arc-resistant switchgear, remote racking and current-limiting protection. Facilities report the result as incident energy in cal/cm² and label equipment accordingly.