This Is AuburnElectronic Theses and Dissertations

Quantification of Ergonomic Risk Factors in Southeastern Logging Operations




Lynch, Stephanie

Type of Degree

PhD Dissertation


Industrial and Systems Engineering


This dissertation aimed to expose and partially fill a gap in logging research regarding ergonomic risk factors associated with operating logging machines in the fully mechanized logging operations typical in the southeastern United States. A review of the existing literature showed that this research was a novel contribution to logging and occupational safety and health research. A survey was developed to quantify self-reported exposure to ergonomic risk factors encountered in the cab of a logging machine and incidence of neck and back pain and prevalence of musculoskeletal disorder (MSD) diagnosis. Of the 157 machine operators who responded, 10.5% (16) reported a MSD diagnosis, 74.3% (113) reported at least mild back pain over the past year, and 71.7% (109) reported at least mild neck pain over the past year. These results led to the development of a study to examine the variability of ergonomic risk factors among logging machines and machine operators. The exposures were most pronounced with skidder operators, but further investigation into this proved difficult with the low n (11). Time was the only independent variable with significant correlation to whole body vibration (WBV) exposure. Limiting time spent operating the skidder would lower lifetime exposure of skidder operators to WBV and likely reduce pain and incidence of MSDs in the logging workforce. However, most crews operate with a single operator per machine and rotation could be problematic due to production demands and the exposure of more employees to higher WBV levels, albeit for less time over a lifetime. An intervention at the design level would be far more effective.