Assessment of system interaction experience in nuclear power plants

The issue of system interaction events in nuclear power plants was originally raised because of the concern about certain types of dependent failures in nuclear power-plant safety-related systems. This article discusses the review of operating experience in nuclear power plants performed by the Oak Ridge National Laboratory (ORNL) for the NRC, discusses the trends or significant characteristics of the events identified by the ORNL review, identifies those system interaction events adequately addressed by existing regulatory and/ or utility actions to prevent (or limit) the occurrence and consequences, and makes recommendations for further action to resolve safety concerns deemed not yet adequately addressed by existing regulatory and/or utility actions.