A Hierarchical Job Analysis System for Assessing Physical Work Barriers

Knowledge of physical work requirements is necessary for determining if a job can be performed by a given person or population. It is also necessary for assessing the risk of fatigue, discomfort and musculoskeletal disease. We have proposed a hierarchical job analysis system that includes four levels of analysis. Level I is based on worker and supervisor interviews and provides descriptions of work tasks, materials, equipment, work environment and activities that may challenge a given person's work capacity or result in excess risk of injury or illness. A Level II analysis is based on direct work site observations and measurements and provides additional quantification of the data obtained from Level I. A Level III analysis is based on expert ratings of ergonomic stresses: repetition, force, contact stress and posture of each task. A Level IV analysis uses instrumentation, e.g., goniometers, electromyography, force gages and accelerometers, to provide quantification of specific task attributes.