Abstract: A granulator operator and a granulator operator trainee were loading dry composition consisting of magnesium, butadiene-acrylonitrile dry rubber, acetone, polytetrafluoroethylene, and methyl ethyl ketone into a granulator machine. The employees' normal duties consisted of transporting the composition to a processing building with a battery-operated golf cart and a small trailer. They would then hand carry the composition inside to be loaded into the granulator machine. After the operator and trainee left the building, the control room operator would activate the granulator remotely from another building and monitor the operation by closed-circuit television. On completion of the granulation process, the granulator operator and trainee would reenter the building, unload the finished product, and take it outside to the trailer. The process would be repeated until all of the material was processed. Normally, there would have been only a single employee performing the duties of a granulator operator. However, a new granulator operator was being trained. At one point during the operation, the granulator operator was inside the building loading composition into the granulator, and the trainee was taking a container of granulated composition back to the trailer. The trainee was outside the building. An explosion occurred, demolishing the building and fatally injuring the granulator operator and the trainee. The granulator operator died from central nervous system traumatic injuries, and the trainee died of exsanguination due to bilateral hemothoraces. The explosion was likely caused either by a discharge of static electricity or by the accidental activation of the granulator machine by the control room operator. The employees had been working with the combustible materials wearing excessively worn protective clothing and without required protective gloves.