“Multi-risk NaTech vulnerability indicator: A step further”

NaTech events involve technological disasters triggered by natural hazards, leading to hazardous material releases. Their multi-risk nature necessitates comprehensive vulnerability assessments to enhance system preparedness. This research presents a further step towards a multi-risk NaTech vulnerability assessment for industrial plants, refining a previous methodology with reference to a case study. A wide flexible selection of natural hazards is proposed, emphasizing the need for a “location priority factor” that considers hazard spatial influence, the conditional probability of NaTech events based on industrial macro-sectors, and cascading effects between hazards. Additionally, interactions among neighboring infrastructures are introduced as an extra hazard factor. To ensure consistency with prior research and historical NaTech data, a broader set of harmonized industrial item categories is defined. The study highlights the dynamic vulnerability of critical items within a plant, considering their layout proximity and functional interconnections. Moreover, multi-risk assessment is improved by integrating quantitative criteria for ratings derived from historical NaTech analyses. An enhanced index for assessing major industrial accident potential based on hazardous substance criteria is proposed in alignment with European legislation. The proposed decision matrix combining independent evaluations of infrastructure and substance-related factors may support risk assessment through varying levels of tolerance, guiding preparedness strategies for industrial systems.