In August of 1993, EPRI initiated a project to perform an evaluation o
f;the application of various methodologies for performing Abnormal Con
ditions and Events (ACE) analysis on computer systems used in nuclear
plants. This paper discusses the application of ACE analysis technique
s to two systems designed for the Tennessee Valley Authority (TVA) Bro
wns Ferry Nuclear (BFN) plant. Further details can be obtained from EP
RI TR-104595, ''Abnormal Conditions and Events Analysis for Instrument
ation and Controls Systems''[1] which is scheduled for publication in
December, 1994.