UNITED STATES
DEPARTMENT OF LABOR

Abstract: At 12:15 p.m. on October 13, 2017, Employee #1, a crew leader, and his crew were removing the old transformer and replacing it with a new one. The power was su pplied to the transformer by an underground cable, originating at the overhead A -phase power line. The phase-to-phase voltage was 13.2kV and the phase-to-ground voltage was 7620v. The underground cable was rated to handle as great as 600 a mperes. The crew needed to isolate and de-energize the transformer prior to rem oving it. There were two underground cables coming off of the A-phase overhead power line and neither one was labeled or identified, so the employees needed to test the amperage of the cables to determine which cable was associated with th e transformer to be replaced and which cable fed power to an unrelated loop. Em ployee #1 used an insulated bucket truck to raise himself approximately 35 feet, to access the underground cable at the pole where it met the overhead power lin e. The employee was using an Amprobe ACDC-100 TMRS amperage/voltage tester, rat ed for up to 800 amperes, to attempt to determine the correct cable. He receive d an irregular or faulty reading that was inconclusive and thought that the mete r was malfunctioning. The employee lowered himself to the ground and obtained t he wire leads for the testing equipment, which are intended to be used for volta ge testing at a maximum rated voltage of 600 volts. He ascended back to the wor k area. Employee #1 touched the positive probe lead of his tool to the primary conductor and touched the negative lead to the concentric neutral of the same ca ble, causing a phase-to-ground contact and resulting in an arc flash. The blown fuse created a very loud popping sound. The employee, now covered in soot, low ered himself to the ground and began to remove his personal protective equipment which included a hard hat, safety glasses, rubber sleeves, rubber gloves, and l eather gloves, as well as FR clothing. He was transported to a nearby hospital and treated for second degree burns to his forehead, cheeks, chin, and left ear. The employee was release from the hospital the following day.