The objective of the present study was to determine whether differences in the frictional properties of a floor surface may affect the kinematics and kinetics of pushing and pulling. Eight male participants were required to push and pull a four-wheeled trolley over two level surfaces, on which were mounted floor coverings with good (safety floor) and reduced (standard floor) frictional properties. A psychophysical approach was used to determine the initial maximum acceptable horizontal force required to move the trolley over a short distance (3 m). Three-dimensional (3D) hand and ground reaction forces and 3D postures were measured during initial force exertions. The results showed that psychophysically derived measures of initial horizontal force and horizontal components of hand forces did not differ significantly between floor surfaces. Despite the ability to exert similar forces, the measured maximum coefficient of friction varied according to floor surface. These changes reflected significant alterations in vertical and horizontal components of ground reaction and vertical hand forces, suggesting that participants had maximized the frictional properties available to them. Postures also changed as a consequence of floor surface, with significant changes occurring in knee flexion and trunk extension. This study has shown that handlers involved in the pushing and pulling of trolleys are capable of adjusting posture and the direction of hand and foot forces in order to compensate for reduced levels of floor friction. This has particular relevance when assessing the musculoskeletal loads imposed on the handler and the likely mechanisms of injury resulting from variations in floor conditions when workers undertake pushing and pulling tasks in the workplace.

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Pedestrian slipping involves a number of factors including the nature of the floor and whether it is contaminated, the type and condition of footwear and environmental conditions as well as the physical and mental capabilities of the individual who slips. It is the interaction ofal! these different factors which will determine whether a slip accident is likely to occur. This paper will develop a risk assessment based approach to slipping so as to give due regard to all the important contributory factors. Worked examples of risk assessments will be presented to demonstrate ways of assessing and controlling the slip potential of any given situation. These examples will beused to show that quick, easy and inexpensive interventions are often capable of significantly reducing the likelihood of a slipping accident.

Eight male subjects performed pushing and pulling tasks on 2 level floor surfaces having good and reduced resistance to slipping. Using a four wheel industrial trolley, 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 forces foreach of 4 experimental conditions. Mean initial maximum acceptable forces were 439N (slip-resistant surface/pushing), 430N (slip-resistant surface/pulling), 453N (slippery surface/pushing), and 410N (slippery surface/pulling), with differences betweenconditions non-significant. Thus, for these subjects, maximum acceptable forces were independent of the floor surfaces used. This was despite significant differences (p