Evaluation of the frequency of musculoskeletal disorders and work posture analysis by RULA method in workers of an auto- part manufacturing company

Intruduction: Musculoskeletal disorders are among the most common disorders due to ergonomic risk factors. This study was designed to evaluate the frequency of musculoskeletal disorders in an auto-part manufacturing company in 2010. This descriptive-analytic study was conducted on 94 welders and operators of an auto-part manufacturing company. The method of sampling was census. We used NMQ and RULA method for evaluation of MSDs and Work postures. Data was analyzed using SPSS (ver. 17). Mean age of the subjects was 30.44 years (range: 20-56 years). The age group with the most frequent musculoskeletal disorders was 20-29 years (52.1%). Mean employment duration of the subjects was 5.2 years (range: 0-12 years). According to the results of NMQ, 70.2% of the subjects had experienced pain or discomfort in one of the areas of musculoskeletal system. According to RULA method 50.95% of subjects had RULA score=7 which takes place in action level 4. There was a statistically significant relationship between age and employment duration and musculoskeletal disorders (p<0.05). This study showed that musculoskeletal disorders were more frequent in low back. Considering that the action level of 4 was the most frequent one among the workers (50.9%), immediate ergonomic intervention is necessary.