Abstract: At 3:07 p.m. on June 27, 2019, an employee plugged and patched a steel radial tubeless semi-trailer tire and mounted it on a steel wheel. The employee sprayed starting fluid inside the tire and ignited it with a propane torch. The explosion seated the bead and the employee inflated the tire to approximately 100 psi. The employee placed the outside tire and aluminum wheel assembly on the axle and hand threaded 10 lug nuts one or two turns onto the studs. The employee retrieved an air impact wrench and bent over in front of the wheel to begin tightening the lug nuts. There was bead failure on the inside dual causing a sudden release of air that forced the outside wheel to strike the employee in the head and chest area. The hand tightened lug nuts were forced off and the employee was knocked backwards approximately 13 feet and was killed when the employee struck the right rear area of another semi-trailer that was backed in the next stall.