Interventional ergonomic study to correct and improve working postures and decrease discomfort in assembly workers of an electronic industry

Musculoskeletal disorders (MSDs) are a major cause of time loss, costs and work force injuries in the workplace. Awkward working posture is a main risk factor for developing MSDs. This study was conducted among assembly workers of an electronic industry with the objective of implementing an interventional ergonomic program to reduce postural stress on neck and trunk and to minimize awkward working postures. This interventional study was conducted on 81 assembly workers of an electronic industry. Nordic musculoskeletal questionnaire was used to determine prevalence of MSDs. Numeric rating scale was applied to evaluate body discomfort before and after the intervention (using a magnification lenses to improve visibility of the parts). Statistical analysis including independent t-test was performed using SPSS (version 16) software. The results showed that MSDs occurred among assembly workers at high rate in neck, lower back, and shoulder/upper arm regions (more than 75%). After intervention, significant discomfort decrement was observed in neck, shoulder/upper arm, lower back, elbows and lower arm regions together with the whole body (p<0.05). More than 90% of the assemblers reported that using the magnification lenses facilitated assembly operation and was comfortable. After the intervention, 89% of the workers evaluated working conditions better as compared with that of before the intervention. It was indicated that using magnification lenses reduced discomfort in different body regions as well as the whole body. It could, therefore be expected that its application of magnification lenses would decrease MSDs of different body regions in long term. Findings showed assemblers satisfaction when using the lenses as well as effectiveness of the lenses application in manufacturing process.