Abstract: Employee #1, the foreman of a pile driving crew, was approximately 130 ft above ground, tied off to pile driving leads at the position where the trip was caught on the hammer. He had his left hand in an area where, when the trip moved inward, there would not be enough room for his hand to pass the dog sticking out from the pile hammer. Employee #1 was releasing the trip mechanism from the pile hammer. The 160 ft tall, 30 in. leads to the D-36 Delmage diesel hammer were on the 3900-W Manitowoc crawler crane. His left hand became caught between the trip mechanism and the dog extending out from the hammer. The skin, muscle, and tendons were torn down to the bone from the back of his hand from just below the wrist out toward the fingers. Employee #1 required hospitalization.