Citation

Haslam RA, Boocock M, Lemon P, Thorpe S. Safety Sci. 2002; 40(7-8): 625-637.

Copyright

(Copyright © 2002, Elsevier Publishing)

DOI

unavailable

PMID

unavailable

Abstract

Eight male subjects performed pushing and pulling tasks on two level floor surfaces having good and reduced resistance to slipping. Using a four wheel industrial trolley (hand cart), adapted so that the force required to move it could be varied by adding weights to boxes attached to either side, a psychophysical approach was used to determine maximum acceptable loads for 4 experimental conditions. Mean maximum acceptable trolley loads were 439 N (slip-resistant surface/pushing), 430 N (slip-resistant surface/pulling), 453 N (slippery surface/pushing), and 410 N (slippery surface/pulling), with differences between conditions non-significant. The maximum acceptable trolley loads were independent of the floor surfaces used. This was despite differences in ground reaction forces between the two flooring conditions (PP less than 0.001). Explanations for these findings include the possibility that subjects may have modified their posture and technique to compensate for poorer footing. Alternatively, subjects may have given little regard to slipping when making their assessment of the maximum load acceptable for the task. It is suggested that a threshold effect may exist, necessitating lower levels of friction or a higher frequency of exposure, before subjects will be prompted to modify their judgements of maximum acceptable load.