Evaluation of postural instability and impact forces during ingress and egress of scissor lifts at elevations

Workers are at risk when entering or exiting elevated scissor lifts. In this study, we recorded ground shear forces and postural instability from 22 construction workers while they performed ingress and egress between a scissor lift and an adjacent work surface with varying lift gate opening designs, horizontal and vertical gaps, and sloped work surfaces. From the results of this study, we observed higher peak ground shear forces when using a bar-and-chain opening, with larger horizontal gap, with the lift surface more than 8 inches below the work surface, and having a sloped (26 degrees) work surface. Similar trends were observed for postural instability except the influence of vertical distance was not significant. To reduce slip/trip/fall risk and postural instability of workers while entering or exiting an elevated scissor lift, we suggest scissor lifts be equipped with a gate-type opening to replace the bar-and-chain design. We also suggest the lift surface be placed no more than 0.2 m lower than the work surface and the horizontal gap is as small as possible. Selecting a non-sloped surface to exit or enter a scissor lift is also desirable.