The use of reliability centered maintenance methods becomes more and more important in all the industrial fields to increase the competitiveness of the installations. They must mainly allow the improvement of the management of equipments in terms of their maximum availability and minimum costs starting from the reliability data obtained by the processing of the historical information stored during the exploitation on the constituting components and applying suitable methods for the definition, on their basis, of the maintenance strategies and their improvement at system level. In this frame, ENEA (an Italian Research Institute), in collaboration with some European industries and within the Contract with the European Community N degrees BRPR-CT96-0211, is developing an innovative software tool aimed to the obtainment of the above results. The database is a fundamental device of this software tool since it allows the interpretation of the experience cumulated during the exploitation of the installation by the storing of historical rough data on its components and the processing of reliability data on their basis. The paper contains a detailed description of the main features of the database and of its constituting records and structure.