2013 | Zongliang Jiang, North Carolina A & T State University
In the tree care industry, dozens of fatalities occur each year and the rate of accidents resulting in lost work time was documented to be four to five times higher than all-industry averages. One of the leading causes for fatalities is falls. The industry standard (Z.133) does not require arborists to be tied-in twice when using handsaws. This could lead to the climbing rope being cut accidentally by the handsaw used in tree pruning, resulting in a fall accident. The objectives of the proposed project are to (1) survey ISA certified arborists to identify common work practices, safety concerns, and risk factors in tree pruning and (2) recruit ISA certified arborists to participate in controlled lab experiments in a simulated tree-pruning setting, to investigate the impacts of identified risk factors on the risk of falls resulting from rope failure due to contact with handsaw blades. This proposed project focuses on the human factors of tree care workers as they respond to various task conditions and requirements, to address the risks of falls and seek evidence-based mechanisms that will help design safer and more ergonomic equipment and work practices to prevent fall-related hazards from occurring in the first place.
Tree care is one of the most dangerous industries and tree care workers face much larger risks than other occupations. In the tree care industry, falling is one of the leading causes for fatalities. This project investigated fall risk factors in arborists from a human factors perspective to help find effective ergonomics and safety
solutions. There were two phases in this study. The first phase was conducting field research that aimed to survey ISA certified arborists at their work sites to identify common work practices, safety concerns, and perceived risk factors. Interview results from the local tree care companies revealed the importance of protocol, training, and protection. The second phase of the study was conducting an empirical study in the biomechanics laboratory equipped with motion analysis devices at North Carolina A&T to quantify the impact of the risk factors such as rope representation, work condition (suspension vs. standing), and handsaw design on tree care worker safety. Human subjects who were free of discomfort or injury in their limbs or low back were recruited to participate in the experiment. Results from the statistical analysis revealed the significant impact of risk factors on worker safety in tree pruning tasks. Findings of this project will contribute to ergonomics and safety solutions for the tree care industry.