BACKGROUND: On a sunny spring day in the Appalachians, a tracked feller-buncher was selectively harvesting a timber stand that contained underbrush from past ice storms. It had rained the day before.
PERSONAL CHARACTERISTICS: The 56-year-old logger/feller-buncher operator had many years of experience in the woods and had been a state certified/trained logger approximately 25 years. There was a two-way radio in the machine, and the operator was wearing his hard hat.
UNSAFE ACTS AND CONDITIONS: The operator was traveling uphill at a slight angle. With the steep, erratic terrain, part of the front of the tracks was off the ground. The operator was unaware of a small root system just under the surface of the ground from an uphill poplar tree. He had failed to fasten his safety belt and had a tool box in the cab that was not secured.
ACCIDENT: The operator had the boom uphill cutting a small sapling, and the bouncing of the boom caused the tracks to slide on the underground roots. The operator was unable to counter the slide with his boom. The machine continued to slide downhill, and when it dug into the ground it flipped sideways downhill. Since the cab was leveled uphill it created a whipping action of several feet, with extreme force, to the operator inside the cab. Other crew members saw the accident and hurried to the machine to get the door open immediately, but it took a few seconds for the operator to shut off the machine because he was disoriented. After getting the operator out, a skidder operator reached in and used the radio to get help.
INJURY: The operator had been thrown from his seat to the top of the cab. A small sledge hammer bounced out of the tool box and broke his nose. He also sustained several cuts and bruises from wrenches.
RECOMMENDATIONS FOR CORRECTION: l Survey the cutting area to make sure rock outcroppings and root systems do not prevent the tracks from gripping the surface. Understand the effect of slope, rough ground, and machine position/orientation on equipment stability. l Always wear seat belts. l Provide a means of mutual communication for all employees in remote areas so they can alert someone quickly in an emergency. l Secure or remove all objects that may become dangerous in the cab if a rollover occurs. l Operators should regularly check the secondary escape release mechanisms from the outside and inside. Knobs should only be hand tight and required tools should be readily accessible.
Courtesy of the Forest Resources Association: https://forestresources.org/