Abstract: At approximately 6:44 p.m., Employee #1 was on a service call to repair a 900R20 truck tire on a multi-piece rim. He used a portable tire cage to contain the tire and wheel assembly during inflation. After inflation to 100 PSI the tire was left inside the cage for several minutes before removing it. As he stood the tire and wheel up onto the tread he made an examination of the tires side walls. As he leaned over he saw a bulge develop on the side wall, and then an explosion immediately followed. The force from the air pressure ripped his shirt front and blew him backwards. According to a witness he lost consciousness and fell to the ground. Employee #1 was hospitalized for an irregular heart beat.