A switchgear for an electric current includes a switching assembly that can be switched between an open state and a closed state; a control mechanism including a trigger member for triggering the switching of the switching assembly to the open state; a housing including lateral walls. The lateral walls are elastically deformable when the pressure prevailing inside the housing increases, one of the lateral walls including, on its inner face, a rigid protuberance, the deformation of the wall causing a displacement of the protuberance, the protuberance being arranged relative to the trigger member such that its displacement results in the displacement of the trigger member to its triggering position.