Lowboy Operator Struck by Boom Stand Support Arm



On a fall day in the Pacific Northwest, a lowboy operator and a shovel operator were positioning a boom stand on a lowboy trailer in preparation for loading a shovel.

Personal Characteristics

Both the lowboy and shovel operators had prior experience in moving procedures.

Unsafe Acts and Conditions

Their employer had an established procedure for lifting or lowering the boom stand using a chain attached to the grapples of a shovel. Instead, the lowboy operator directed the shovel operator to use the shovel’s grapples to lift the boom stand into place.


The lowboy operator was standing on the trailer’s deck near the rear tires as the shovel operator positioned the boom stand. He was leaning forward and reaching toward the support arm when the grapples slipped off the boom stand. As the boom stand fell towards the deck, it caused the support arm to strike the pin boss.


The support arm flipped up and struck the lowboy operator’s hardhat, causing him a serious head injury.

Recommendations for Corrections

  • Make sure everyone involved understands, communicates, and follows all safety procedures in place for the tasks that they will be performing.
  • Employee work areas must be spaced, and employee duties organized, so the actions of one employee do not create a hazard for any other employee.
  • Lowboy operators should stay in the clear until the boom support is set in place and secured.