Chemical Release and Fire Risk in Flammable-Liquid Storage Facilities: A Twelve-Case Bow-Tie Analysis of Safety Barriers

Introduction: Major releases at flammable-liquid terminals can generate hazardous vapour clouds, fires, explosions and chemical contamination. Accident reports reveal interconnected technical, operational and emergency-control deficiencies. Objectives: To compare documented chemical-release and fire-accident pathways and to identify evidence-based preventive and mitigative safeguards in 12 historical incidents. Methods: A qualitative Bow-Tie synthesis was applied to a purposive twelve-case collection of official investigations. Ten barrier categories were cross-tabulated. Each case-category cell was coded as documented deficiency (D), provisional (P), or unassessed (U); descriptive counts represent report evidence, not barrier failure probabilities. Results: The inherited source-audited working matrix contains 120 case-barrier cells: 15 documented deficiencies, 2 provisional interpretations, and 103 unassessed cells. Independent overfill prevention, electrostatic controls, equipment integrity, gas testing prevention, electrostatic controls, equipment integrity, gas testing, isolation, and maintenance management were recurring themes across different incident pathways. Conclusions: Qualitative Bow-Tie comparison identifies practicable chemical-release prevention priorities, but incomplete case-level evidence prevents estimation of barrier failure probability, toxic exposure dose or comparative reliability. Independent report-page verification remains a prerequisite for stronger inferential claims.