Abstract: On March 16, 2001, Employee #1 was using a torque wrench with a handle approximately 3 ft-long to tighten nuts onto a truck wheel hub. The hub was being secured to an empowered test fixture in a test stand in the laboratory and was not attached to any vehicle. As the 450-ft-lb tightening specification was approached, the washer located between the nut and hub split. The energy released forcefully ejected the torque wrench socket and headed off the nut, causing Employee #1's body to twist. Employee #1's right foot was firmly planted on the floor and his bodily motion caused his right leg to twist, resulting in a fracture.