Complex approach to assessing resilience of critical infrastructure elements

The resilience of elements in a critical infrastructure system is a major factor determining the reliability of services and commodities provided by the critical infrastructure system to society. Resilience can be viewed as a quality which reduces the vulnerability of an element, absorbs the effects of disruptive events, enhances the element's ability to respond and recover, and facilitates its adaptation to disruptive events similar to those encountered in the past. In this respect, resilience assessment plays an important role in ensuring the security and reliability of not only these elements alone, but also of the system as a whole. The paper introduces the CIERA methodology designed for Critical Infrastructure Elements Resilience Assessment. The principle of this method is the statistical assessment of the level of resilience of critical infrastructure elements, involving a complex evaluation of their robustness, their ability to recover functionality after the occurrence of a disruptive event and their capacity to adapt to previous disruptive events. The complex approach thus includes both the assessment of technical and organizational resilience, as well as the identification of weak points in order to strengthen resilience. An example of the application of the CIERA method is presented in the form of a case study focused on assessing the resilience of a selected element of electrical energy infrastructure.