An employee was helping a coworker move material from reprocessing to the film department, which involved attaching a 4-inch hose to a hopper. Once the hose is hooked up, material flows through a filtering system in the hopper. There is a rotary valve at the bottom of the filter. The valve rotates and dumps waste into a container. The hopper was jammed or clogged up, so the employees tried to get it to work by cycling the power. The injured employee was going to feel around the rotary valve for the jam or clog when the rotary valve "sucked his hand up" into it and amputated the distal phalanx of the thumb.