DMAIC steps application to improve ergonomics problem: a case study in coffee manufacturing industry

The health issue related to Musculoskeletal Disorders (MSDs) faced by manufacturing industries’ workers affects the work quality and productivity, commonly due to the tasks performed with unsuitable posture. This study was carried out to assess the level of Ergonomics Risk Factors (ERFs) among shop-floor workers in a coffee manufacturing company, located in northern peninsular of Malaysia. The Six Sigma approach was applied based on Define, Measure, Analyze, Improve and Control (DMAIC) steps. Observation, interviews and self-report surveys were conducted in the Define step to identify the potential tasks that lead to the high level of ergonomics risk. In the Measure step, the Rapid Upper Limb Assessment (RULA) and Rapid Entire Body Assessment (REBA) tools were then used to assess the level of ERF on twenty-three tasks that practice at eight workstations. In the Analyze step, assessment results were evaluated, thus identifying that the lifting task (mixing workstation) has the highest ergonomics risk level (score level 11) and follows by root cause identification. Then, the Improve step focuses on a simple invention proposal, where the optimal solution that fulfills the principles of proper height working procedure and reducing excessive force is applied. The proposed solution shows a significant improvement in ergonomics risk level based on the score value of 3. Lastly, the Control step focuses on sustaining the improved version performance by revising the working procedure according to the solution principles proposed in the previous step.