On random and systematic failures

Abstract The Licensee Event Reports (LERS) for Zion 1 and 2 (1974–April 1979) and 100 design errors compiled by the Oak Ridge National Laboratory (ORNL) for the period 1977–1978 are analyzed. Two general classes of errors, random and systematic, are defined and the latter class is investigated in detail. Systematic errors are studied from various points of view, namely their causes, effects, mode of discovery, and their relation to fragility curves.