Making decisions for incident management in nuclear power plants using probabilistic safety assessment

Abstract

Decisions by management during nuclear power plant operations may have safety-related and economic consequences, and may affect the relationship with external stakeholders such as regulatory authorities. Attributes such as worker exposure to radiation, potential radiation release, negative publicity, and regulatory intervention may conflict with concerns such as loss of income due to plant shutdown or reduced power. This article shows that the combination of probabilistic safety assessment and multi-attribute decision theory offers the potential for a structured decision-making methodology that could take into account risk-related aspects (plant and worker safety, for instance), as well as important factors like economics and regulatory requirements. The difficulties we encountered during the elicitation of utilities, and our solutions to those issues, are discussed. We demonstrate our decision analysis methodology using a case study in incident management—the decision making that follows events emanating from non-safety-related component failures. Particular attention has been paid to the assessment of tradeoffs among different objectives, especially when some of the consequences of decision options can be catastrophic.