Effects of sitting versus standing and scanner type on cashiers

In the retail supermarket industry where cashiers perform repetitive, light manual material-handling tasks when scanning and handling products, report s of musculoskeletal disorders and discomfort are high. Ergonomics tradeoff s exist between sitting and standing postures, which are further confounded by the checkstand design and point-of-sale technology, such as the scanner . A laboratory experiment study was conducted to understand the effects of working position (sitting versus standing) and scanner type (bi-optic versu s single window) on muscle activity, upper limb and spinal posture, and sub jective preference of cashiers. Ten cashiers from a Dutch retailer particip ated in the study. Cashiers exhibited lower muscle activity in the neck and shoulders when standing and using a bi-optic scanner. Shoulder abduction w as also less for standing conditions. In addition, all cashiers preferred u sing the bi-optic scanner with mixed preferences for sitting (n = 6) and st anding (n = 4). Static loading of the muscles was relatively high compared with benchmarks, suggesting that during the task of scanning, cashiers may not have adequate recovery time to prevent fatigue. It is recommended that retailers integrate bi-optic scanners into standing checkstands to minimize postural stress, fatigue and discomfort in cashiers.