OSHA investigates a hospitalized injury due to an arc flash
A crew from the Los Angeles Department of Water & Power was working upgrading the battery room at a receiving substation. (The room provided emergency power for up to 8 hours.) The electric utility had purchased replacement batteries from RSC in Wilmington, CA.
Before starting work that day, the crew connected the newly purchased batteries in series. Two workers had requested insulated tools as well as appropriate personal protective equipment, such as gloves, barriers, and an insulated torque wrench.
None could be provided on that day, but the employer allowed the work to continue.
At about 1:00 p.m., after one worker had connected all the batteries in one rack in series, he made a cross-aisle connection to a second rack. As he was connecting the cross-aisle cable to the last battery on the upper level of the first rack, the other end of the cable dropped. It came too close to the exposed positive terminal of the last battery on the lower level of the same rack, causing an electrical fault.
The ensuing electric arc burned the worker's rubber insulating gloves and melted his left glove into the middle and ring fingers of his left hand.
He sustained second- and third-degree burns, requiring surgeries and hospitalization for several days.
The employer had not trained its employees in the proper procedures for, and hazards of, working with wet cell batteries.
At the time of the reporting, this investigation was still ongoing.