A mill supervisor was killed when he was hit by a piece of a door which blew off an anvil chipper. The incident occurred when a chipper saw knife fell into the conveyor system and damaged the chipper. A metal detector on the conveyor, not properly adjusted, failed to catch the knife. Investigators into this fatality came up with these recommendations to prevent future incidents:

• Establish written procedures so foreign objects do not enter the conveyor system.
• Keep metal detectors adjusted properly so they will prevent objects from entering the system where they can damage machinery and endanger workers.