Abstract: At approximately 1:00 p.m. on June 13, 2003, an employee of Northern California Nail Co. was working on the roof of a 40-foot warehouse nailing roof coverings with a nail gun. He was using a Hitachi nail gun, with Serial Number C315813D. When his air hose got stuck on the roof, he tried to free the hose. In the process, the gun swung to the back of his head. He suffered a puncture wound on the back of his head when his right thumb accidentally tripped the trigger shooting a nail that was 2.125 inches long. The air pressure was approximately 110 psi. Paramedics took him to Saint Francis Hospital in Lynwood, California, for medical treatment. The nail was removed from his head in the hospital, and he was released from the hospital after five days.