Many mining commodities are packaged and shipped using bags. Small bags are typically loaded onto pallets for transport and require a significant amount of manual handling by workers. This specific task of manual bag handling has been associated with the development of musculoskeletal disorders (MSDs), especially low back disorders. This study evaluates the biomechanical demands of different work layouts when performing manual palletizing of small bags, and evaluates the biomechanical stresses associated with different stacking techniques. Results indicate that peak forward bending moments as well as spinal compression and shear forces are higher when the pallet is situated at the side of the conveyor as opposed to the end of the conveyor. At low levels of the pallet, controlled bag placement results in higher peak forward bending moments than stacking at higher levels and when dropping the bag to lower levels. The results of this study will be used to inform the development of an audit tool for bagging operations in the mining industry. RELEVANCE TO INDUSTRY In many cases for workers loading small bags, compression forces exceed the NIOSH criterion of 3400 N. Orientation of the pallet has a significant impact on spinal compression, and positioning the pallet at the end of the conveyor reduces the estimated compressive loading on the lumbar spine by approximately 800 N.

中文翻译：

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手动袋式码垛作业中操作员位置、托盘方向和码垛条件对低回载的影响

许多采矿商品使用袋子包装和运输。小袋子通常装载到托盘上进行运输，需要工人进行大量的人工搬运。这项人工搬运行李的具体任务与肌肉骨骼疾病 (MSD) 的发展有关，尤其是腰部疾病。本研究评估了小袋手动码垛时不同工作布局的生物力学要求，并评估了与不同堆叠技术相关的生物力学应力。结果表明，当托盘位于输送机的一侧而不是输送机的末端时，峰值前向弯矩以及脊柱压缩和剪切力更高。在托盘的低位，与在较高高度堆叠和将袋子掉落到较低高度时相比，受控袋子放置导致更高的峰值前弯力矩。这项研究的结果将用于为采矿业装袋作业的审计工具的开发提供信息。与行业的相关性 在许多情况下，对于装载小袋子的工人来说，压缩力超过 NIOSH 标准 3400 N。托盘的方向对脊柱压缩有重大影响，将托盘放置在输送机的末端会减少估计的压缩载荷腰椎大约 800 N。