Abstract: At 9:30 a.m. on June 12, 2018, an employee was using an cut-off machine (14 inch, HILTI Portable, handheld, internal combustion powered, model Number DSH 700-X 14, Serial Number 0337190138) with a severely worn and damaged cutting disc that was installed incorrectly on the cut-off machine, to make two superficial vertical cuts in a steel strong wall as part of the demolition portion of the wall. A coworker stood nearby to spray water onto the cut location while the employee made the cuts. To avoid standing in an excavation next to where the employee was cutting, the employee had to lean over the excavation to make the cuts. At some point, the employee lost control of the cut-off machine when it kicked back and struck the employee's left arm. The employee was transported to a local hospital, where he was treated for severe lacerations to the left arm.