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Mine Safety and Health Administration MSHA's Accident Prevention Program
Miner's Tip

Torsion Bar Hazards

Safety Something YOU can live with!
Mine Type: Underground Coal
Category: Maintenance

Armed and Dangerous In a recent fatal accident, a miner was performing maintenance on a chain conveyor system when the mounting arm for a hydraulic motor broke loose from its anchor point. The mounting arm rotated upward, cutting through the steps on which the victim was standing, striking the victim's leg and torso resulting in fatal injuries. Torque arms, motor mounting arms, and rollback guards are only a few of the types of torsion bars found around mills and mining operations. Many torque arms on belt drives, face conveyors, etc., are held in place with multiple fasteners and keyways or are loosely "boxed" in to prevent unwanted rotation. A failure of the fastener almost always results in the arm spinning around, usually with enough force to tear up everything in its path. To protect yourself from these swinging hazards:

Reissued: 10-10-2002 
Tag # AP2002-M049

MSHA extends a thank you and a tip of the hardhat to
Dave Podobinski of Washington, PA
a winner of a limited edition sticker and patch.

If you have a tip you would like to pass on, you can e-mail it to If your Miner's tip is selected, you will receive credit in this space.