Estimation of Spinal Loading during Palletizing under Restricted Height and Poor Lighting

Abstract

Many industries have areas with restricted spaces where manual material handling occurs which is oftentimes further complicated by poor lighting. The study objective was to evaluate the spine loading when lifting boxes within restricted height space with different light levels. Ten participants lifted boxes with independent variables: restricted height, light levels, pallet layer, and pallet position. The dependent variables included three-dimension spine loads and rating of perceived exertion. The results indicate that importance of location of the box as well as the restricted height of the space where the box is being lifted (increase of about 1200 N in compression and 160 N in A-P shear). Under general lifting conditions, light level had minimal impact (under 100 N). Gender was also found to have a significant impact for lateral shear and A-P shear forces (males > females for lateral shear but < for A-P shear). Overall, restricted height and location of on the pallet had the greatest impact on the spine loads.