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U.S. Department of Energy
Office of Scientific and Technical Information

The change in risk due to upgrade to a digital reactor protection system

Conference ·
OSTI ID:54600
; ; ;  [1]
  1. Idaho National Engineering Lab., Idaho Falls, ID (United States)
The United States Nuclear Regulatory Commission (NRC) is sponsoring the Idaho National Engineering Laboratory (INEL) to study the risk impact of the upgrade of commercial nuclear power plants (NPPs) from analog to digital instrumentation. It was decided to use a limited probabilistic risk assessment (PRA) methodology to assess the risk impact due to the implementation of digital control systems. The human reliability analysis (HRA)/PRA analysis was to be a pre- and post-upgrade comparison to determine the change in risk. A candidate NPP was selected as the initial step in the analysis process. The selection process entailed reviewing the literature to identify NPPs that had undergone a modification in which a digital control system (DCS) replaced an analog control system. Preference was given to plants where the DCS controlled safety systems. Several NPPs were considered for the candidate plant. The NPP was selected primarily because: (1) it had replaced its existing analog control system with the Westinghouse Eagle-21 Process Protection System (Eagle-21); (2) it had several years experience with the DCS; and (3) the NPP`s management demonstrated a willingness to support the project.
Research Organization:
Nuclear Regulatory Commission, Washington, DC (United States). Office of Nuclear Regulatory Research
DOE Contract Number:
AC07-76ID01570
OSTI ID:
54600
Report Number(s):
NUREG/CP--0139; CONF-9410216--; ON: TI95001469
Country of Publication:
United States
Language:
English