A diversion device is provided for diverting breathing gas, which is laden with CO2, from a pressurized region of an arrangement that includes a breathing mask and serves for delivering a breathing gas at a pressure level that is above the ambient pressure. The device has a tubular stub structure which defines a breathing gas conduit that extends between an inlet cross section on the hose side and an outlet cross section on the mask side, and which is provided, in a region located between the inlet cross section and the outlet cross section, with an outflow orifice portion by way of which the breathing gas to be carried reaches the environment. In a region located between the outflow orifice portion and the outlet cross section on the mask side of the breathing gas conduit, a double-walled structure that surrounds the breathing gas conduit is embodied for sampling the breathing gas to be carried away from a mask interior, while largely circumventing the breathing gas conduit.
