Logic criteria are used in software testing to find inputs that guarantee detecting certain faults. Thus, satisfying a logic criterion guarantees killing certain mutants. Some logic criteria are composed of other criteria. Determining component criterion feasibility can be used as a means to reduce test set size without sacrificing fault detection. This paper introduces a new logic criterion based on component criterion feasibility. Given a predicate in minimal DNF, a determination is made of which component criteria are feasible for individual literals and terms. This in turn provides determination of which criteria are necessary to detect double faults and kill second-order mutants. A test set satisfying this new criterion guarantees detecting the same double faults as a larger test set satisfying another criterion. An empirical study using predicates in avionics software showed that tests sets satisfying the new criterion detected all but one double fault type. For this one double fault type, 99.91% of the double faults were detected and combining equivalent single faults nearly always yielded an equivalent double fault.