Abstract: Employee #1 was in the process of repairing a flat tire on a county dump truck that was in the service center for repair. Employee #1 removed the wheel from the truck and inflated the tire to 40 psi. Employee #1 then wetted-down the tire with water to locate the (leak) problem. Employee #1 found a nail hole, deflated the tire, and removed it from the single piece rim for repair. Employee #1 patched the nail hole from the inside of the tire and the tire was inspected by for damage. No additional damage was observed. Employee #1 remounted the tire on the rim and then placed the tire in the protective tire cage for inflation. The tire was inflated to 100 psi in the cage and inspected again by Employee #1. The tire was removed from the cage for installation on the truck. As Employee #1 was taking the tire to the truck he stopped for a moment to talk with a coworker. Employee #1 was standing beside the tire when the sidewall blew out. The force of the blowout knocked Employee #1 backwards causing him to fall on some tires. Information indicated that Employee #1 was not struck by any pieces of the tire, or by any pieces of the rim, and that the tire and rim never left the ground when the sidewall blew out. The only marks on his body are believed to be from the force of the air escaping from the sidewall of the tire, and from the tires that he fell against. The force of the air from the ruptured sidewall of the tire may have severed an artery causing severe internal bleeding. Employee #1 was taken to the hospital but he died in-route.