A New Methodology for Frequency Estimation of Second or Higher Level Domino Accidents in Chemical and Petrochemical Plants Using Monte Carlo Simulation

Some of the most destructive accidents of 1980s and 90s which occurred in process industries were domino accidents. Although domino accidents are among the most destructive industrial accidents, there are not much pioneering works done on quantification of them. The analytical formulation of the domino accidents is usually complex and need a deep knowledge of probability rules. Even if the case is formulated, errors in calculation such as round-off error, is very probable as the values used all have small quantities and the number of possible scenarios are too high. In this paper, a new methodology based on Monte Carlo Simulation (MCS) technique is proposed for frequency estimation of domino accidents. The applicability and flexibility of this method is evaluated while applying it to estimate domino frequencies in a case study very similar to a real industrial plant. The simulation technique has shown advantages in comparison to analytical probability methods. The major advantage is non-dependency of the accuracy of results to complexity of the system. In addition by using simulation techniques, failure probability can be calculated as a function of time.