Analysis of Root Cause of the Fatal Occupational Accidents in a Gas Refinery Using the Tripod-Beta Method

Introduction: Most critical accidents in different industries are observable, but their severity is also predictable and can be controlled. Provided that accident analysis is properly managed with a preventive approach and based on correct findings, in a principled and realistic manner, root causes, corrective actions, and safety measures regarding accidents are performed. Material and Methods: The present research was a descriptive-analytic study, and the reported and recorded fatal occupational accidents were analyzed in the onshore section of one of the construction refinery projects in the South Pars Gas Refinery over a decade using the Tripod Beta method and then main risk factors, pre-conditions, and underlying causes, as well as the existing protective barriers, were identified, and an accidents tree was drawn. Results: The analysis of fatal occupational accidents showed that 26 immediate causes, 39 preconditions, and 50 underlying causes were involved in those accidents. Six key risk factors include lack of responsibility/organizational impact (57.8%), training (22.2%), hardware or tools and equipment (6.7%), maintenance management (6.7%), work procedures (4.4%), and Error Enforcing conditions (2.2%) had the largest share of the occurrence of accidents. Conclusion: More than 80% of fatal occupational accidents can be controlled by modifying the two main factors, responsibility and organization and training. Therefore, implementing the total productive maintenance method, effective monitoring of staff work, hiring staff with sufficient knowledge and skills, and improving training indicators will increase understanding of hazard sources, improve safety and reduce accidents.