Ergonomic evaluation of the effects of handle types on garden tools

The objective of this study was to evaluate quantitatively the effects of h andle types of garden tools on ergonomic effectiveness, user satisfaction i n terms of work performance, and subjective judgment of tactile feel and co ntrol. Shoveling performance, hand grip force and electromyography (EMG), t ask workload, and subjective ratings of perceived exertion were measured wh ile using three types of garden tasks/tools (shovel, rake, and hoe) with th ree different handle types: a conventional wood handle and two more fibergl ass handle. The most effective measure for shovels was the relative efficie ncy of shovel performance, that is, shovel performance divided by task work load. A hollow fiberglass handle was 12% more efficient than either a wood or solid fiberglass handle. The grip force and EMG analyses showed a simila r effect, with a solid or hollow fiberglass handle requiring significantly less effort than a wood handle. Subjective ratings of the perceived exertio n were also lowest for a hollow fiberglass handle. A hollow fiberglass hand le showed better physiological efficiency and better subjective acceptabili ty for comfort, tactile feel, and decreased slipperiness.