NIOSH, 2000 Aug. :1-40
Researchers from the National Institute for Occupational Safety and Health (NIOSH) conducted a health hazard evaluation (HHE) of the risks for musculoskeletal disorders of the upper limbs and back to beverage delivery personnel during keg delivery from the Coors Distributing Company (CDC) and evaluated a recently introduced ergonomic intervention, a friction feed pulley system (FPS) with the trade-name Keg Boy TM. The objective of the hazard evaluation was to identify job tasks in the keg delivery cycle which may increase the risk for musculoskeletal injuries and to provide recommendations to decrease and prevent such injuries. The primary purpose of the intervention evaluation was to determine if the friction feed pulley system (FPS) was effective in reducing the risk of musculoskeletal disorders during the truck unload phase of delivery. Analysis of postural and heart rate data from the job showed that unloading kegs from the delivery truck and moving kegs in the cooler of the establishment to which the delivery was made represented the tasks with the highest biomechanical and physiologic demand. Specifically, lifts of kegs from the delivery truck and from the ground in the confined space of the cooler were both determined to produce back compressions of the lower back (L5/S1, 5cm) averaging 1065 lbs (+/- 117, +/- 118), which exceed the NIOSH Recommended Compression Limit (RCL) of 770 lbs. Another work activity that caused significant back compression forces was "wheeling kegs inside the establishment" (level ground) which averaged 996 +/- 89 lbs. The mean weight lifted per day was 18,532 +/- 3915 lbs by the deliverymen during beer delivery routes. The FPS was determined to offer a biomechanical advantage over the traditional manual lift method by inducing significantly lower back compression levels (p < 0.0001) during the delivery truck unload phase. Use of the FPS to unload kegs from the truck was associated with the lowest average back compression (303 lbs +/- 128) of all keg lifting tasks. The FPS lift and traditional lift were not shown to be significantly different physiologically in terms of heart rate mean. Although the FPS was shown to produce a significantly lower heart rate increase than the traditional lift (p ~ 0.02), it also produced a borderline significantly greater heart rate maximum than the traditional lift (p ~ 0.06) and heart rate peak percent maximum (p ~ 0.06). The FPS averaged almost 7 times as long to use (40 seconds versus 6 seconds) than the traditional manual method. Much of the difference in time between the two systems is attributed to a lack of experience with the FPS.
Musculoskeletal-system-disorders; Cumulative-trauma-disorders; Ergonomics; Engineering-controls; Manual-materials-handling; Hazard-Confirmed; Region-8; Manual-lifting; Materials-handling; Materials-handling-equipment
Hazard Evaluation and Technical Assistance; Field Studies
NTIS Accession No.
Musculoskeletal System Disorders
National Institute for Occupational Safety and Health