Abstract: At 11:45 a.m. on October 10, 2014, an employee was repairing a 9.5 ton school bus with the left rear axle on 5 ton jack stand. The jack stand frame was reinforced sometime in the the past with metal stock welded onto the frame and potentially weakening the frame. The employee was raising the bus to reposition the jack stand to gain access to the shock mounting bolts. A piece of metal stock was found underneath the bus which might have been used as a spacer on top of the air jack piston to gain additional height. The lift became unstable and slipped allowing the bus to fall and collapse the jack stand. The bus frame pinned the employee and compressed his rib cage so he could not breathe. The employee was killed.