Effect of the risk arising from working postures on mental workload: An experimental study

As the workload of the employees increase, the performance of the worker decreases, their capacity decrease, the inability to complete the task on time and the number of errors increase. In order to protect employees from these undesirable effects, it is important to measure the mental workload level of workers. In this thesis, the hypothesis that poor work postures, lifting, incorrect holding and carrying actions in the workplace affects the mental workload of the employees was proposed. In order to obtain the proposed hypothesis data, 84 operators were selected from an integrated meat-dairy food facility in Konya and their operations were analyzed with ergonomic risk assessment methods REBA, RULA and NIOSH lifting equation methods. In addition, using the data of the surveys conducted with these 84 operators, the mental workload value of each worker was obtained with NASA TLX workload measurement method. For the purpose of the study, the relationship between the changes in the mental load levels found by NASA TLX method and the changes in risk levels found by REBA, RULA and NIOSH Lifting Equation methods was investigated with multiple regression analysis which is an analysis method that provides the cause-effect relationship between the variables. As a result of the study, it was found that the increments in the difficulties of the body postures covering the whole body of the employees increase the mental workload level of the employees. In addition, increases and decreases in the risk levels of lifting or lowering tasks have been shown to affect the mental workload of the employee.