Abstract
The NIOSH equation was formulated to evaluate lifting and lowering tasks with respect to given conditions such as the load being handled, displacement from the origin to destination and other factors. On the other hand, the OWAS method is a widely applied method in the analysis and improvement of working posture. It should be noted that working posture plays a key role in material handling. When using the NIOSH equation and OWAS method, data from actual observations have to be gathered before any improvements can be made. However, this research proposes a method based on the application principles of the NIOSH equation and OWAS method, to generate improvement ideas even before any material handling tasks are carried out. This suggests that if vital information such as the size (dimension, weight) of the load, its position and displacement with respect to the worker from start to end of material handling tasks, layout, material handling process and equipment etc. are known, then the corresponding work posture can be determined. Therefore, if the necessary information on the working conditions is known before the work is done, it is possible to predict the working posture. In addition, not only the working posture can be predicted but also the work posture changes, dangers and underlying hazards. This study examines the predicted working posture through the use of a human body model. Nine basic posture patterns are designed to emulate the elements of material handling tasks. Using a formula, working posture changes are obtained from joint angle changes of the human body model expressed in a polynomial. Then, the working posture is analyzed through the use of posture and action codes of the OWAS method. From the mathematical computation, using a material handling example of a human model, the procedure of formulating the OWAS posture and action codes is shown.
