Assessment of major accidents triggered by lightning

The present study aimed at the analysis of past accidents caused by lightning and the development of a framework for the quantitative assessment of these events. The analysis of past accidents suggests that lightning events are the most frequent cause of technological accidents in chemical and process plants. Fires, mainly affecting storage farms and involving atmospheric storage tanks, are the most frequent final scenario associated to such events. The development of a quantitative methodology for the assessment of the risk due to major accidents triggered by lightning was thus addressed. The starting point of the methodology is the assessment of the frequency and severity of the lightning event. Different damage states were defined, and damage probability functions were derived. The overall frequency and intensity of loss of containment were thus determined. Standard models for consequence analysis allowed the assessment of the physical effects of the final scenarios.