Case report: #71-234-2023
Issued by: Death Assessment and Control Program in Washington State
Date of report: February 27, 2023
A 28-year-old tree trimmer was part of a team of four that removed a 127-foot-tall fir tree from a residential property. The tree care and landscaping contractor’s employer was not on site to provide oversight. The crew planned to use a lowering device (port-a-wrap) to lower parts of trees and branches. However, since the rope was not long enough for them, they tied two ropes together. The knot tying the ropes together didn’t fit in the Port-a-Wrap, so instead they wrapped the rope twice around the tree to use friction to lower the tree sections. A climber then worked from the tree – fastening and cutting sections while the tree cutter and another worker held the rope to lower the sections to the ground. The climber cut a 330-pound piece from the tree. It fell about 30 cm before the rope to which it was attached became taut. The weight of the section caused an impact load on the rope, lifting the pruner and other worker off the ground. Workers struggled to gain control of the section as momentum pulled them toward an embankment. The tree cutter lost his grip on the rope, tripped and fell backwards down the embankment, hitting his head on a rock. He died at the scene of the accident.
To prevent similar occurrences, employers should:
- Develop guidelines for accident prevention programs that require workplace hazard analysis with worker participation for each workplace. A JHA would have identified the dangerous rigging and lowering practices as well as the risk of a collision through the uncontrolled boom section.
- Have a qualified arborist make decisions about safe tree felling practices and provide direct training and supervision to workers involved in tree work.
- Use ANSI Z133 American National Standard for Arboricultural Operations – Safety Requirements to train workers to ensure they use proper tree felling methods and understand and account for additional forces resulting from rigging design, rope angles and number of lines and /or result in pieces of line that act on any rigging or anchor points.
www.safetyandhealthmagazine.com
https://www.safetyandhealthmagazine.com/articles/23694-face-report-tree-trimmer-dies-when-tree-removal-rigging-fails