Abstract
The interaction between natural hazards and industrial installations handling hazardous substances can lead to cascading accidents known as NaTech events. Climate change has increased the frequency and intensity of extreme weather, amplifying the vulnerability of chemical and process plants. Under the Seveso III Directive (2012/18/EU), operators are required to identify major accident scenarios triggered by natural events, including fires, explosions, and toxic releases. Among natural hazards, floods are among the most significant threats in Italy and across Europe. This paper focuses on flood-induced NaTech scenarios, addressing both direct and indirect accident pathways, including failures of utilities and ancillary systems. Based on analyses of past industrial accidents, the study identifies equipment and plant components most exposed to flooding and extreme weather. Best practices, investigation approaches, and risk assessment elements are discussed to support the definition of effective prevention and protection measures within the Seveso Safety Management System for the Prevention of Major Accidents.
