Efficient Construction of Minimal Cut Sets from Fault Trees

A formal method and an algorithm are presented to determine minimal cut sets (MCSs) from fault trees. The method is based upon segmenting the tree, constructing MCSs of subtrees and subsequent expanding into the MCS of the original tree. The major advantage of the method is the direct determination of MCSs up to any order required. More particularly, the algorithm DICOMICS allows straightforward analyses for all those cases (large trees, high order cut sets, repeated elements) where present combinatorial and Monte Carlo techniques are not effective. Compared with other structural algorithms now in use, DICOMICS provides a near optimal effective construction of MCSs. Thus, even when there are many redundant cut sets, computer implementations yield a substantial reduction of computing steps and effort. Hand calculation and interactive programming are also possible.