This thesis is a part of the ANR BARPPRO project. This research program studies this influence of the protection barrier during an explosion detonation. The goal of this project is to establish fast-computation methods of area classification effects to help the industrial to design the protection barrier on the SEVESO sites. One from abacus, for configurations in 2D geometry on specified parameters used, with an accuracy of +/- 5%. The other from a fast-running method based on broken lines for configurations in 2D and 3D geometries, but the accuracy is +/- 30%. This study includes three approaches: experimental, numerical simulation and analytical approaches. The experimental part studies several geometries of the protection barrier for a gaseous explosion (stoichiometric propane-oxygen mixture) at small scales. The experimental configurations used to validate the numerical simulation tool constituted of the HERA software and the TERA 100 supercomputer. The overpressure charts were able to generate from the numerical results (3125 configurations of the barrier for a TNT charge). The analysis of these results allows to establish different recommendations in the design of the protection barrier. The study of the different physical phenomena present has also helped to set up a fast-running method based on the geometrical, empirical and analytical relations. All these tools will enable an engineer to analyze and estimate the evolution of overpressure around the barrier as a function of the site’s dimensions.