Assessment of manual lifting activities using worker expertise : a comparison of two worker populations

This study demonstrates the use of human expertise in evaluating manual lifting activities in industry. The objective of this study was to document how workers from different cultures and with different physical characteristics evaluate physical effort in industrial lifting activities. The documentation is based on a study involving three hundred and seventy-nine workers in Hong Kong. Participants were asked to evaluate the interactive effort of three lifting variables: weight of load, horizontal distance and height of lift. Logistic regression analysis was used to model the effort as a function of the lifting input variables. The input variables were subsequently classified according to the relationship between the input and output variables. The results showed that human personal knowledge and expertise can be successfully used to evaluate the physical effort required for the performance of different lifting tasks. More specifically, there were no differences in cognitive reasoning patterns in evaluating the physical effort between the Hong Kong and the US workers. The participants from the two different cultures both rated the weight of load as the most important variable in evaluating lifting activities.Department of Rehabilitation Science