Comparing the Results of Three Ergonomic Assessment Tools

The outcome of an ergonomic assessment underlies and is followed by the decisions on where and when an intervention is required; therefore, selecting a suitable method indirectly affects the effectiveness of an ergonomics program. Currently, available ergonomics assessment tools vary over a wide range, some of which can be interchangeably used for similar purposes. This could make the practitioners confuse to choose the most appropriate tool. QEC, ManTRA and MFA are of those methods having to do with routine manual tasks which their distinctions have never been drawn. The objective of this study was to compare the results of these three ergonomics methods to determine their agreements with one another and correlations with workers' musculoskeletal discomforts. The tools were applied to 350 manual tasks by several ergonomics experts, as was the Cornel Musculoskeletal Questionnaire to the workers working on those tasks. The outputs of the three methods were compared with one another as well as with the workers' musculoskeletal discomforts rate. Of the methods, MFA evaluated the tasks as at risk in more moderate way than the other methods and had the most correlation with the workers' musculoskeletal discomforts. ManTRA was also found as the most lenient approach which tended to ignore some risky tasks of the work systems. In contrast, QEC was the strictest of the three and would classify a task as high/very high risk more than the other tools in this study.