Analysis of domino scenarios in chemical and process facilities operating in harsh environmental conditions

In the framework of chemical and process industry, accidental fires may lead to damages to equipment with severe consequences and possible domino effects. The availability and effectiveness of safety measures, aimed at reducing the risk associated with this type of events, may be strongly affected and decreased if the facility is located in harsh environment, due to complicating meteorological factors and extreme temperatures. The present work is aimed at defining a structured approach to the quantitative assessment of fired domino events accounting for the influence of harsh environment conditions on safety barriers performance. A specific metric is defined in order to consider the external factors related to harsh environments on the determination of hardware and emergency safety barriers availability and effectiveness, with a specific focus on the evaluation of the time-scale of emergency response. A dedicated event tree analysis is then applied implementing the obtained performance values of the safety barriers, in order to support the quantitative assessment of accident frequency associated with domino scenarios. The present method is applied to the analysis of a chemical facility located in harsh environmental conditions.