This communication presents the interest of the use of the methods for the operating safety studies and the analysis of control-command systems. Therefore, we present the various concepts of operating safety of industrial installations. Our contribution is to locate the main methods used in the operating safety studies over the methods used for the analysis and design of control-command systems for searching for a hybridization of these methods. In fact, we investigate firstly the SADT, FMDS and Safe-SADT methods and on the other hand both Extented SADT and SA/RT methods.