Proposing a Mathematical Model and Lower Bound for Ergonomic Job Rotation Scheduling Problem

Work in industrial workshops and heavy activities has effects on the health of workers and in terms of occupational hazards associated with many risks for them. Since in the industrial units there are different works in terms of ergonomic load and hardship of work, the occupational hazards can be reduced by job rotation scheduling. In this paper, using reduction approach, the ergonomic job rotation scheduling problem (EJRP) is reduced to parallel machine scheduling problem so that its exact methods (such as branch and bound method) are used to solve the EJRP. Furthermore, according to the proposed reduction, the lower bounds for parallel machine scheduling problem also applied for branch and bound solving method. The main aim of this research is providing an optimal scheduling for job rotation by applying human factors engineering approach in order to minimize the maximum workload on the staffs.