Abstract
Climate change and global warming are intensifying both the frequency and the magnitude of weather-related natural events, further increasing the likelihood of cascading sequences triggered by natural disasters. These events can lead to fires, explosions, and release of dangerous materials, resulting in severe consequences for Safety, Health, and Environment. Furthermore, heat waves generally affect wide geographical areas, potentially impacting many installations simultaneously. Increasingly frequent and intense heat waves can influence, mainly: Deformation of tanks, pipelines, and other equipment, compromising their structural integrity and increasing the risk of rupture and consequent loss of containment; Uncontrolled increase of internal pressure in process equipment, possibly exceeding design limits and leading to mechanical failure; Stability of certain chemicals, increasing the likelihood of uncontrolled reactions, fires, or explosions; Auto-ignition of materials and substances present in the plant; Performance of cooling systems, reducing their effectiveness and raising the risk of overheating of machinery and equipment; Proper functioning of instrumentation and safety systems; Acceleration of corrosion processes in metallic materials; Operational capabilities of personnel, increasing the probability of human errors and accidents. The aim of this paper is to propose a methodology for the preliminary assessment of NaTech risk induced by heat waves, to identify the most critical technical systems within a major accident hazard establishment. The proposed method is index-based and defined as: IRhw = f (IHhw, IVhw, IEhw)where IRhw (Heat Waves Risk Index), IHhw (Heat Waves Hazard Index), IVhw (Heat Waves Vulnerability Index) and IEhw (Heat Waves Exposure Index).
Keywords: NaTech Risk, Index-Based Method, Major Accident Hazard, Extreme Weather, Heat
