Abstract: Petrochemical enterprises involve multiple categories of hazardous chemicals that are flammable, explosive, and toxic. To effectively prevent the occurrence of major and extra-large accidents in petrochemical production, it is essential to conduct scientific and comprehensive safety assessment and risk evaluation of chemical installations and critical safety facilities. This study systematically integrates the interrelationships and application logic among three evaluation methodologies—HAZOP, LOPA and risk matrix—to develop a specific risk evaluation model. The model was validated through application in the safety assessment of cooling water systems for key facilities in chemical production processes, demonstrating its scientific validity and feasibility. The findings provide valuable references for process safety management and risk classification control system development in petrochemical enterprises.

Key words: HAZOP, LOPA, risk matrix, risk classification and control, dual prevention mechanism