A 54-year-old male farmer (victim) died after he was pinned beneath the hopper of a rock picker. It had three main components, a three-bar reel, a pick-up head and a steel collection hopper. The pick-up head was controlled by two hydraulic cylinders, one located on each side of the unit. These cylinders controlled the pick-up head and also raised and lowered the hopper to empty the unit. The day before the incident occurred, an employee of the victim used a tractor and the rock picker to clear rocks from a field until a failure occurred in the unit's hydraulic system. The employee left the tractor and rock picker in the field and notified the victim of the break down. The next day, the victim drove his pickup truck to the field where the rock picker was to repair it. Although a failure had occurred within the hydraulic system, he was able to raise the hopper to its dumping position. He also hooked one end of a chain to the front edge of the hopper and the other end to the hitch of his truck. After raising the hopper he entered the area directly behind the pick-up head which is the area the hopper occupies when lowered. Several wrenches were found near the victim which indicated that he entered the area to repair the hydraulic system. Apparently while repairing the unit, something changed such that the raised hopper could not be held by the parked truck. The hopper lowered to its down position and the victim was pinned beneath it. Two employees of the victim happened to drive by the field, thought things seemed out of place and investigated. They found the victim pinned beneath the hopper and placed a call to emergency personnel who arrived shortly after they were contacted. They checked the victim for signs of life and determined that he was deceased. They placed inflation bags under the rock picker, inflated the bags and removed the victim. MN FACE investigators concluded that, in order to reduce the likelihood of similar occurrences, the following guidelines should be followed: 1. Equipment should be designed with safety devices to support raised components while maintenance or general repair work is being performed

and, 2. Workers should never enter areas around or under machines unless the machine and/or all machine components are securely locked so as to prevent workers from being injured.