The index for evaluation of operational efficiency of limit condition of emergency (I.OPà.CLE), developed by the Italian Department of Civil Protection in 2013, is a probabilistic method aimed to assess the operational efficiency of a municipal contingency plan in case of earthquake occurrence. If the physical elements of this system, assimilated to a network, are not able to resist the earthquake, the whole emergency management can be seriously hindered. The system and the element characteristics are provided by the analysis of the limit condition of emergency (LCE). The method, described in previous papers by the same authors, relies on the formulation of synthetic indices expressing the probability for the emergency system and its relevant components to preserve the operational capability for seismic scenario events with different return periods. The paper describes the results of an experimental application of I.OPà.CLE on a sample of 30 analyses of LCE. Each LCE was analyzed in two different layouts: the original one, as conceived by each municipality or appointed institution, and a minimal one, as obtained by reducing the number of physical components to the essential ones. In total 60 I.OPà.CLE analyses were carried out. The former part of the paper deals with the description of LCE analyses of the sample and their physical components, also by a cross comparison through original and minimal systems. In the second part the results achieved by processing I.OPà.CLE are presented and discussed, so as to draw some final considerations in terms of operational efficiency for the two considered configurations.