Abstract: At 9:30 p.m. on January 10, 2020, an employee and Coworker #1, both Maintenance Electricians, were dispatched to troubleshoot a crane that had lost power. The crane is one of many located in a steel yard within a shipbuilding facility. After not being able to identify the problem, the employee (the Lead) called the maintenance shop to update Coworker #2 (Maintenance Supervisor) about the situation. Coworker #2 sent Coworker #3 (Maintenance Technician) to help. After no success, Coworker #3 called Coworker #2 who came out to assist with the troubleshooting. Coworker #2 went inside the building and opened the door to a 4,160 volt load interrupt switch (LIS) box and directed the employee get his Fluke 117 hand-held multimeter. Coworker #2 then directed the employee to start probing busbars on the LIS with the Fluke. The employee probed the bottom row of busbars and then continued probing while Coworker #2 stood behind him. As the employee probed the middle busbar an arc flash occurred that burned both his hands. The employee incurred 2nd degree electrical burns to both hands, requiring hospitalization.