An electric switch including a stationary contact that is annular. The switch comprises a gastight enclosure (2), a conductor bar (8) of axis (D), a stationary contact (12) presenting a contact zone (22) of substantially annular shape, a switch element (40), e.g. on the conductor bar, that is movable in the axial direction of the axis (D) between a first position in which it penetrates in part into the stationary contact (12) to establish electrical contact between the conductor bar (8) and the stationary contact (12), and a second position in which it interrupts said contact. The stationary contact, which is in the form of a ring that is circular or elongate, e.g. elliptical, surrounds the conductor bar (8), at least in part.