The approach to critical infrastructure’s safety assessment based on integarion of a priori and a posterioti safety analysis results is considered in the paper. The result integration is suggested as a main principle of risk analysis of infrastructure and systems characterized by high accident consequences severity for human beings and natural environment. The possible relations between a priori and a posterioti models are considered. This approach allows adjusting the parameters of a priori model used for infrastructure safety analysis. It allows increasing a credibility of safety analysis results and validity of decisions to decrease risk to acceptable level.
critical infrastructure, safety, a priori and a posterioti analysis