Iranian Journal of Ergonomics

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Introduction: Musculoskeletal disorders (MSDs) are the main causes of work related injuries and disabilities in developed as well as developing countries. Few studies have considered different interactive effects of individual and work-related factors on MSDs, simultaneously. Methods and Materials: Data were gathered by Nordic questionnaire and Quick Exposure Check (QEC) method and were analyzed using logistic regression model in order to study the correlation between the prevalence and intensity of MSDs and individual and work-related factors. Results: More than half of all participants (61.6%) reported suffering from one form of MSDs during the past 6 months. Results showed that risk factors such as work stress, sleeping position, lifestyle and poor posture had an important role in the prevalence and intensity of MSDs. Discussion: The effect of a risk factor is constantly in interaction with other risk factors, and is modified by other factors. Participatory ergonomic intervention programs, work station intervention, ergo stress intervention and life-style interventions were suggested in order to decrease the prevalence and intensity of MSDs.

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Introduction: Metro driving is one of the newest jobs in Iran. Due to the lack of studies about train drivers’ workload, there is no comprehensive information about factors that effect workload. This study aimed at analyzing the factors that may effect driver workload, in order to recommend control measures.

Methods: In this mixed method study, data generation was done through field observations, document reviews, individual interviews, focus group interviews, and focus group discussions. In order to perform field data collection, the institute for occupational ergonomics and CCD Design and Ergonomics Ltd’s developed tools were used. Directed content analysis was used for qualitative data analysis.

Results: Overall, 65 factors were extracted as the factors that may effect driver workload. The extracted factors were drawn on a fishbone diagram, over 8 categories, including management, supervision and organizational climate, infrastructure, job design, journey, and environmental as distal factors and time pressure, information exchanges, and individual factors as proximal factors.

Conclusions: Some of the distal factors are the nature of an urban transport system, so the only amendment is compensatory programs, and some of them could be resolved by long-term plans. Workload of train drivers could be reduced with a focus on the proximal factors in the short-term, and the distal factors in the long-term.