Abstract: On November 13, 2006, Employee #1, a journeyman electrician, was inside an energized electrical substation cubicle, cleaning a switch gear. The input voltage to the equipment was 12,600 volts AC. Employee #1 had recently installed the equipment and it was about to undergo testing by a representative of the cubicle's manufacturer in order to be released for use by the Chicago Transit Authority to supply power to the third rail on a length of elevated train tracks. An arc flash/blast occurred, setting off a chain reaction between the three electrical phase connections on the cubicle where the circuit breaker switch gear coupled to the cubicle (and would normally complete the circuit to the load). Employee #1 sustained severe burns and was transported to the hospital, where he died two days later. At the time of the accident, Employee #1 had been working for 18 months on power distribution equipment. Three coworkers were in the area when the arc fault occurred, but they were standing outside the flash protection boundary. At the time this report was written, the Cook County Medical Examiner was still investigating the accident and suspected that current flow through Employee #1's body had also contributed to his death.