Risk-Based Multilevel Methodology to Stress Test Critical Infrastructure Systems

Making communities safer requires better tools to identify, quantify, and manage risks. Among the most important tools are stress tests, originally designed to test the risk posed by nuclear power plants. A complementary harmonized multilevel stress test for nonnuclear civil infrastructure systems against natural hazards is proposed. Each stress test level is characterized by a different scope and a different level of risk analysis complexity to suit different civil infrastructure systems, different hazards, and different risks. The stress test consists of the following phases. First, the goals and the methods for the risk analysis are defined. The test is then performed at the component and system levels, followed by a verification of the findings. A penalty system is defined to adjust the output of the risk assessment according to the limitations of the risk analysis methods used. The adjusted risk assessment results are then passed to a grading system to determine the outcome of the stress test. Finally, the risk assessment results are reported, and the stress test outcomes are communicated to stakeholders and authorities.