A comparison of risk assessment of single and combination manual handling tasks: 1. maximum acceptable weight measures.
A comparison of risk assessment of single and combination manual handling tasks: 1. maximum acceptable weight measures.
复制标题
单一和组合人工搬运任务的风险评估比较： 1. 最大可接受重量测量。
作者：
L. Straker;M. Stevenson;L. Twomey
许多手工搬运活动涉及拉、提、抬、降和推的组合，但很少有研究调查如何评估这种组合任务的风险。大多数建议都假设一项组合任务可以被分成几个部分进行评估。这项研究的目的是比较单一手工操作任务和组合任务中评估的风险。9名男性和9名女性参加了一项研究，以确定不同频率(组合任务1分钟-1和3分钟-1，单一任务3分钟-1和6分钟-1)和高度(地板、关节、肩膀)下单一任务和组合任务的最大可接受重量(MAWS)。组合任务由单个任务(拉、举、提、降和推)中的每一个组成。使用具有特定对比的重复测量方差分析，将每个组合任务的MAW与组成其的单个任务的MAW进行比较。在12项比较中的至少一项中，发现每个单一任务的最大值与其相关的组合任务最大值不同。结论是，目前使用单一任务最大似然估计来估计组合任务中的风险是不可接受的。采用逐步回归的方法，建立了基于单任务MAWS的组合任务MAW预测模型。虽然确定系数达到了0.8左右，但有人认为，由于具体情况的性质，使用单一任务最大似然法对组合任务风险进行预测可能会导致不可接受的风险误差。
Many manual handling activities involve combinations of pull, lift, carry, lower and push, yet few studies have investigated how to assess the risk of such combination tasks. Most recommendations assume that a combination task can be split into its components for assessment. The aim of this study was to compare the risks assessed in single manual handling tasks with those in combination tasks. Nine male and nine female students participated in a study to determine Maximum Acceptable Weights (MAWs) in single and combination tasks at different frequencies (1 min-1 and 3 min-1 for combination tasks and 3 min-1 and 6 min-1 for single tasks) and heights (floor, knuckle, shoulder). Combination tasks consisted of one each of the single tasks (pull, lift, carry, lower and push). The MAW of each combination task was compared to the MAWs of the single tasks of which it was composed using repeated measures analysis of variance with specified contrasts. In at least one of the 12 comparisons each single task MAW was found to be different from its related combination task MAW. It was concluded that the current use of single task MAWs to estimate the risk in combination tasks was unacceptable. Prediction models for combination task MAWs based on single tasks MAWs were also developed, using step-wise regression. Although coefficients of determination of around 0.8 were achieved it was argued that owing to their situation-specific nature the prediction of combination task risk using single task MAWs was likely to result in unacceptable risk errors.