This thesis deals with the problem of hydrogen explosions in nuclear power plants, and evaluates if the reactor hall is to be seen as a safety barrier for such events. Today, the reactor hall is not seen as a safety barrier that is able to withstand an internal explosion. In the analysis Abaqus was used for the FEM calculations, where a main scenario of a wall subjected to a hydrogen explosion was used. In conclusion, the results showed that a reactor hall with the assumed dimensions cannot be seen as a safety barrier, since the deformation after a hydrogen explosion near the LEL was too great. However, it is also concluded that with increased wall and rebar dimensions it is possible to construct a wall of this kind that fulfills the requirements of a safety barrier.