Micro incident analysis framework to assess safety and resilience in the operation of safe critical systems: A case study in a nuclear power plant

Safety in modern organizations, comprised of many nested levels with different types of coupling between them, must be managed by a control structure embedded in this adaptive sociotechnical system. The resilience of sociotechnical critical systems still relies on human ability to handle unexpected events adequately. In this study, based on a schematic view of a nuclear power plant control system composed of three structural system layers, planning, operation, and hardware, we present a framework to analyze micro incidents during nuclear power plant operation. The analysis show operators' control actions used to solve small conflicts that arose at the operational layer, and how they marshaled the resources required for their action/cognition, i.e. the material, social, and cultural characteristics of the environment. The micro incident framework enables an anticipated view of operators' control actions, providing processes for systemic analysis and critical thinking about the possibility that relatively small problematic situations in the loosely coupled system layers may lead to negative outcomes at some future time. (C) 2007 Elsevier Ltd. All rights reserved.