Development of a Risk Assessment System for Navigational Obstacles Considering Collision and Pollution Risks

Navigational obstacles can impede safe vessel operation and cause secondary accidents, necessitating their rapid removal. To conduct these removal operations efficiently, it is necessary to comprehensively assess the effects of obstacles on both collision and pollution risks. However, comprehensive risk assessments that simultaneously consider both collision and pollution risks are lacking. In this study, a navigational obstacle risk assessment system based on the fuzzy set theory was developed to support the rapid removal of obstacles. The system comprises three main components: (i) a collision risk assessment model utilizing Monte Carlo simulation, (ii) a pollution risk assessment model employing a hazard management structure for sinking vessels, and (iii) a fuzzy set-based evaluation system that integrates risk indices derived from these models to infer the comprehensive risk. The results of the simulation-based case study confirm that the developed system provides reliable risk assessment by comprehensively considering both the collision and pollution risks. The system is sensitive to changes in the risk levels and effectively reflects the realistic conditions, thereby overcoming the limitations of existing research. This demonstrates its potential as a valuable tool for decision-making for rapid removal of navigational obstacles.