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0807 PD: Bunker silo hazards

Dennis J. Murphy Published on 02 August 2007

Recently a Pennsylvania farm worker was killed while collecting a silage sample. He was doing his normal sampling procedure by walking to the face of the silage and getting a sample for the dairy nutritionist and sales representative.

The silage face was correct (no overhang or undercut). While getting the sample the pit collapsed from the bottom, not the top, and engulfed the worker, resulting in his death.

Apparently, a frozen section of silage came loose, allowing a larger amount of the face to collapse and bury the worker.

There are several hazards associated with a bunker silo, and not all are as obvious as are some other types of farm hazards.

Everyone who has to work around a bunker silo should be able to recognize the risks and apply good safety habits. Keep these hazards and practices in mind:

Reduce rollover risks

  • Use heavy, wide-based roll-over protective structures tractors (ROPS) when packing silage. Buckle the seat belt.

  • Do not exceed a 3-to-1 slope (1 foot rise per 3 feet horizontal distance) on the “progressive wedge” fill.

  • Use sighting rails to guide the fill and packing equipment.

  • Do not exceed wall height with fill.

  • Back packing tractors and dump trucks up the silage slope rather than along the slope. Reduce dump truck risks

  • Dump loads of forage on as level a surface as possible; avoid ruts and low tire pressure.

  • Dump loads with the dump bed facing up the slope.

  • Expect dump truck drivers to buckle their seat belts. Reduce risks of silage face collapse

  • Use equipment that can reach to the top of the silage face during feedout to prevent undercutting.

  • All silage handling, sampling or observations should be made after an equipment operator brings the silage away from the silage pile with the unloading equipment.

  • Permit no one to stand at the silage face if it exceeds their height.

  • Be aware that a clean shaved silage face may still collapse if the weight of silage above the area exceeds the strength of the silage at the base of the pile. This could occur with frozen silage, damp silage packed on top of drier silage, etc.  PD

—From Penn State Dairy Digest, April 2007

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