Blast waves are able to produce structural damage to process equipment even at great distances from the source point of an explosion. A loss of containment may follow and, if hazardous substances are released, relevant secondary scenarios may be triggered, resulting in domino effects. The present study was focused on the assessment of the expected structural damage and of the associated intensity of loss of containment of process vessels loaded by blast waves. Hence, a knowledge-based fuzzy set analysis was used to assess the expected overall probability of occurrence of different damage states defined for several categories of process equipment items. The fuzzy approach was also used to obtain specific threshold values for the escalation sequences (domino effects), taking into account the hazard due to the expected secondary scenarios caused by the loss of containment following blast wave impact. (c) 2005 Elsevier Ltd. All rights reserved.