Iranian Journal of Ergonomics

Introduction: Musculoskeletal disorders (MSDs) represent one of the leading causes of occupational injury and disability in the developed and industrially developing countries. This study was conducted to investigate the prevalence of MSDs and evaluate the risk of these disorders among welders of a steel manufacturing industry.

Materials and Methods: This descriptive-analytical study was achieved on all 243 welders employed in a steel manufacturing industry. Nordic Musculoskeletal Questionnaire (NMQ) was used to study the prevalence of MSDs. Meanwhile, QEC technique was employed to evaluate the risk of exposure to these disorders. For data analysis, central statistical indices, T-test and Chi-square test were used.

Results: The results suggested the highest prevalence of symptoms of musculoskeletal disorders in low back, trunk and knees, respectively. QEC technique showed a high and very high risk of exposure to MSDs in 64.6 % of welders.

Introduction: Different studies around the world have shown that Work-Related Musculoskeletal Disorders (WMSDs) are the causes of lost time, absenteeism, and disability. The purpose of this study was to investigate the prevalence rate of musculoskeletal disorders (WMSDs) and to evaluate their ergonomic risk factors and determine the effect of ergonomic intervention on awkward postures among workers of Saipa Diesel Truck manufacturing plants.
Methods: This interventional study (Before-after) was conducted on 130 workers of 2 largest truck-manufacturing plants in Iran. The prevalence rate of MSDs and ergonomic risk factors was assessed by valid and reliable translated Body Map Questionnaire (BM) and Quick Exposure Check (QEC) method, respectively.
Results: According to Body Map results, 87.5% of participants had MSDs at least in one of their eleven body regions during the previous year, before study. The highest prevalence rate of MSDs was observed in lower back (51.5%) and foot area (18.5%). Chi square test revealed that the prevalence rate of MSDs was higher among those with higher QEC risk level (P < 0.001). Results also indicated the significant effect of ergonomic interventions on reducing the prevalence rate of MSDs and QEC risk level (P < 0.001).
Conclusions: This study showed that the prevalence rate of MSDs and QEC risk levels among workers was significantly high. Therefore, it can be mentioned that the need for early ergonomic interventions is felt in all industrial units of these truck-manufacturing plants.

Background and Objectives: Using appropriate methods for ergonomic risk assessment of musculoskeletal disorders has an important role in controlling these risks and providing workforce health. The purpose of this study was to evaluate the feasibility of applying WERA method to assess the risk of musculoskeletal disorders through its correlation with the results of QEC.
Methods: This descriptive-analytical study was performed on 72 employees of workshop sections of a modern brick industry. Data were collected using a Nordic questionnaire to assess the prevalence of musculoskeletal disorders in the past 12 months and WERA and QEC methods to ergonomic risk assessment of musculoskeletal disorders. Data were analyzed by SPSS 18.
Results: The prevalence of back, shoulder, neck and wrist disorders were 41.7%, 20.8%, 16.7% and 33.3%, respectively. Results of WERA showed that 88.9% of subjects had medium action level and 11.1% had high action level. In QEC method, 6.9% of subjects had exposure level ‘one’, 20.8% of subjects had exposure level ‘two’, 48.6% of subjects had exposure level ‘three’, and 23.7% of subjects had exposure level ‘four’. The correlation between QEC total score and prevalence of musculoskeletal disorders was (r=0.67, P=0.038). The correlation coefficient between the final scores of the two methods was (r=0.53, P=0.021).
Conclusion: Examination of the correlation between the mean scores of the two methods indicated a moderate correlation between them. Correlation between prevalence of disorders and QEC and WERA scores showed that QEC results were more consistent with Nordic results and it can be said that QEC method was more suitable for ergonomic assessment of musculoskeletal disorders risk for different tasks in this study.