An electrical gas-blast circuit breaker has two stationary, hollow switching pieces (2) each having a nozzle (4) and a piston/cylinder blowing device (9). The extinguishing gas is supplied from its compression space (14) via passage openings (13) in an insulating material tube (12) to the interruption path (5) during disconnection, in order to extinguish the arc. In order to increase the turbulence of the extinguishing gas flow in the critical constricted region (17) of the nozzles (4), said nozzles (4) are provided with channels (15) which connect the space outside the nozzle (4) to the constricted region (17) in the nozzle (4). The channels (15) can be designed as radial holes or as holes which are arranged to run obliquely with respect to the longitudinal axis. This design of the stationary switching pieces (2) is suitable for high-voltage power circuit breakers which use SF6 as the extinguishing gas. <IMAGE>
