A comparison of productivity and physical demands during parcel delivery using a standard and a prototype electric courier truck

Abstract Courier drivers are at risk for the development of fatigue and Musculoskeletal Disorders (MSDs) due to frequent awkward lifting and carrying of parcels. A functional prototype of a redesigned courier truck represented a potentially valuable engineering control to reduce courier drivers' MSD risk. Specifically, the prototype courier truck was evaluated for its ability to reduce double-handling of packages between carts and the truck, decrease the lifting of carts on/off the truck and reduce lifting packages in awkward positions. Ten courier drivers performed a simulated delivery route with 18 stops while surface electromyography of the forearms, shoulders and lumbar spine were monitored with a simultaneous video recording. Low back loading for each lift was calculated based upon video analysis. The prototype courier truck showed substantial and statistically significant reductions in total delivery time (−29.5%), and the reduction was especially noticeable for stops using a cart. The cumulative compression and integrated electromyograms also showed reductions for the prototype courier truck. Peak and average loads did not, however, change appreciably. The prototype courier truck met the first three goals; however, it did not measurably affect the demands of lifting and moving packages within the truck itself. Further development is intended to address this issue. Relevance to industry The redesign of this transportation equipment achieved some reductions in mechanical loading as well as improvements in productivity.

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