Evaluating System Cascading Failures

This article shares methods used to evaluate system cascading failures. A cascading failure occurs when a problem is passed from one subsystem to a downstream subsystem creating a domino effect that undermines system efficiency and effectiveness. First, the basics of system evaluation theory (SET) are reviewed. Then drawing on different examples from the evaluation of emergency response systems the article describes how a) standard operating procedures (SOPs) can be used to locate possible system cascading failure trigger points, and b) mock exercises and secondary data are used to evaluate these trigger points. The discussion highlights the need to expand SET's conceptualization to include within subsystem cascading failures in addition to between subsystem cascading failures. The extent to which program evaluation methods can be adapted for use in system evaluation is also discussed.