Iranian Journal of Ergonomics

Introduction: In the modern industrial world, the health of the employees in different Occupations can be influenced by the interaction of various risk factors. So, the purpose of present study was to assess and analyze the relationship between the factors including shift work, job stress, job satisfaction and health in a petrochemical industry.
Materials & Methods: The present study was conducted using analytical and cross-sectional method. The statistical population was all employees of a petrochemical company (4000 people). Using the Cochran formula, a sample of 360 individuals were selected using simple random sampling method. Data was collected using a high reliability integrated questionnaire (Cronbach’s alpha = 0.83). Data was analyzed using SPSS22.0.
Results: The analytical results of relationship between shift work, occupational stress, occupational satisfaction and health showed that all hypotheses in the conceptual model were approved and there was a significant relationship between these factors (P<0.001). Also, the results showed that, in addition to the direct effect of shift work on health, due to the effect on occupational stress and occupational satisfaction, it was indirectly related to health (P <0.001).
Conclusion: The findings indicated that shift work as a direct factor and as a mediator and indirect factor through impact on factors such as occupational satisfaction and stress can affect the health of employees. Therefore, considering this organizational phenomenon and its redesign or its change can play an important role in increasing the level of occupational health and motivation as well as organizational productivity.

Background and Aim: Occupational accidents are recognized as one of the major concerns in the mining industry. The purpose of this study was to analyze the incidence of occupational accidents in a mine for 10 years using Human Factor Analysis and Classification System (HFACS).
Method: This cross-sectional study was carried out on 664 mining accidents during 2009-2018. The tools used in this study included accident reporting checklists, human factors analysis and classification system (HFACS), and a team approach to analyze these accidents. Data analysis was performed using IBM SPSS AMOS v. 23.0.
Results: The accident frequency rate (AFR) was 15.10±3.34. The results of 10-years accident analysis in this mine based on HFACS model showed that the highest contribution of each parameter to the four layers including unsafe acts, preconditions for unsafe acts, unsafe supervision and organizational influences were respectively devoted to perceptual error (64.4%), Physical environment (29.5%), inadequate supervision (59.6%), and organizational process (65.6%). The results of structural equation modeling showed that the AFR is directly and indirectly affected by the layers of the HFACS model (P<0.05). The most significant impact on the AFR was related to the unsafe acts layer.
Conclusion: The findings of this study indicated that all four causal layers of human factors were effective in mine accidents, in addition the HFACS model is highly effective for unsafe acts-based accidents analysis, so it can be used for future planning to reduce accidents in the mining sector.