Assessing external explosions and their probabilities

External hazards such as explosions can be safety significant contributors to the risk in case of operation of industrial plants. The procedure to assess external hazard explosion pressure waves within probabilistic safety assessment starts with a screening procedure in order to determine scope and content of the assessment. The second step is to choose an appropriate approach in case that a full scope analysis has to be performed. Several methods can be applied to evaluate the probability of occurrence of an external explosion event. The presented results indicate that the probability of occurrence of external explosion pressure waves can be successfully assessed by means of the Monte Carlo simulation, in particular in difficult site-specific conditions.