Abstract: A movable and a stationary contact element are tubularly structured for the purpose of axially discharging arc gases. A blast nozzle is associated in a fixed reference position with respect to one of the contact elements. A narrowest location or throat of the blast nozzle is positioned forwardly of the end of this one contact element and is closed by the other contact element in the cut-on position of the gas-blast switch. An inlet of the blast nozzle communicates with a pump space bounded by a cylinder and a piston. The contact element with which the blast nozzle is associated displaceably extends through the piston. The pump space can be pressurized during a cut-off stroke. Both of the contact elements are provided with related outlets in their related regions which are remote from the free ends of the contact elements. At least in the cut-off position the outlets interconnect an interior space formed in the related contact element and a blow-out space.