Abstract: On October 17, 2012, Employee #1 was riding on a locomotive traveling to the excavation area at the Bay Tunnel Construction Project. As the locomotive moved through the trailing gear area that encircles the train track, and behind the tunnel-boring machine; the front passenger compartment guardrail on the locomotive struck the open lid of an elevated metal toolbox. The toolbox projected into the train's path of travel. The guardrail struck the employee's right leg, fracturing the tibia and fibula, and dislocating his knee. The employee was transported to Stanford University Hospital, where surgeries were performed to repair the break in his right tibia and right knee. Employee #1 was released after five days.