The aim of this thesis is to analyse and improve, by a systematic approach, the maintenance strategies used for the gas systems of the CERN LHC experiment detectors. These systems are very complex, consisting of numerous racks and components that need to be continuously in run phase to provide the gas mixture to the detectors. Therefore, it is essential to establish a structured and robust approach, such as Reliability Centered Maintenance (RCM), to set a methodology with the ultimate goal of increasing the reliability and availability of these systems. In particular, the analysis focuses on the gas systems for the Resistive Plate Chambers (RPC) detectors, chosen as a reference.