Abstract: At approximately 8:00 a.m. on March 21, 2014, Employee #1, employed by a construction contractor, was part of a crew installing a concrete patio at a single family residence. He was operating a Skilsaw circular power saw to cut a notch in a 2-inch by 4-inch piece of lumber. His intention was to create a screen for leveling out the concrete about to be poured into the concrete form for the patio. Employee #1 held onto the piece of wood with his left hand and operated the saw with his right hand. As he initiated a plunge cut into the wood, the saw kicked back. The saw blade made contact with Employee #1's left thumb, cutting it off at the joint. Emergency services were called, and Employee #1 was transported to Sutter Hospital, where he was admitted and treated for the finger amputation. It was not possible to reattach the finger. Employee #1 remained hospitalized overnight. At the time of this report, Employee #1 had not returned to work. This event was investigated by Cal/OSHA.