Abstract: At 12:45 p.m. on October 9, 2017, Employee #1, employed by a construction framing company, was engaged in carpentry work at a residential construction project. He was operating a left-handed Porter Cable Circular Saw, Model 743, to cut a block of wood from a piece of scrap lumber that measured 4 inches by 6 inches by 36 inches long. The wood was supported by a stack of 0.625-inch drywall that was set on wood blocks on a garage concrete floor. Employee #1 was holding the circular saw with his right hand and the piece of lumber with his left hand. As he cut into the lumber, the circular saw kicked back, and its blade struck his left hand. Emergency services were called, and Employee #1 was transported to the hospital. He was admitted and treated for severe lacerations of the hand which resulted in the amputation of his left thumb.