Unveiling The “Invisible Killer”: A Structural Equation Model of Human Factors and Compliance Influencing Enclosed Space Safety Performance on Merchant Ships

Despite extensive regulatory frameworks, fatal accidents in enclosed space operations onboard ships continue to occur, highlighting the limited understanding of how human factors interact to influence safety outcomes in such high-risk environments. This study aims to develop and test an integrated model examining the influence of safety leadership, safety competence, and mental resilience on enclosed space safety performance, with safety awareness and procedural compliance as mediating mechanisms. A quantitative approach using Structural Equation Modeling (SEM-PLS) was applied to data collected from 350 merchant ship officers in Indonesia. The results reveal that all hypothesized relationships are significant. Safety leadership, safety competence, and mental resilience positively affect safety awareness and procedural compliance. Safety awareness significantly enhances procedural compliance, while both variables significantly improve safety performance, with procedural compliance emerging as the strongest predictor. Mediation analysis confirms that safety awareness and procedural compliance function as critical cognitive and behavioral pathways linking human factors to safety outcomes. This study contributes to maritime safety literature by providing an integrated human factors framework for understanding and improving safety performance in enclosed space operations.