An exhalation valve arrangement (22; 122) for an exhalation line of a ventilation apparatus for artificial ventilation of patients, the exhalation valve arrangement (22; 122) being flow-capable in an exhalation flow direction and encompassing: - an upstream respiratory gas conduit (54; 154) that extends along a first conduit path and is connected or connectable to a portion, coming from the patient, of the exhalation line; - a downstream respiratory gas conduit (58; 158) that extends along a second conduit path and is connected or connectable to a respiratory gas sink, for example the external environment; - a valve subassembly (63; 163) which comprises a valve body (64; 164) and a valve seat (66; 166) and which is provided between the upstream and the downstream respiratory gas conduit (54, 58; 154, 158) in such a way that, in the context of a predetermined first respiratory gas overpressure in the upstream respiratory gas conduit (54; 154) relative to the downstream respiratory gas conduit (58; 158), it permits an expiratory respiratory gas flow from the upstream respiratory gas conduit (54; 154) into the downstream respiratory gas conduit (58; 158); and in the context of a predetermined second respiratory gas overpressure in the downstream respiratory gas conduit (58; 158) relative to the upstream respiratory gas conduit (54; 154), it blocks a gas flow from the downstream respiratory gas conduit (58; 158) into the upstream respiratory gas conduit (54; 154), wherein the exhalation valve arrangement (22; 122) comprises a bypass chamber (74; 174) which communicates in terms of flow mechanics with the upstream respiratory gas conduit (54; 154) and is embodied for attachment of a gas pressure sensor, characterized in that the bypass chamber (74; 174) extends, proceeding from the upstream respiratory gas conduit (54; 154), into the region of the downstream respiratory gas conduit (58; 158) is embodied there for attachment of the gas pressure sensor. - an upstream respiratory gas conduit (54; 154) that extends along a first conduit path and is connected or connectable to a portion, coming from the patient, of the exhalation line; - a downstream respiratory gas conduit (58; 158) that extends along a second conduit path and is connected or connectable to a respiratory gas sink, for example the external environment; - a valve subassembly (63; 163) which comprises a valve body (64; 164) and a valve seat (66; 166) and which is provided between the upstream and the downstream respiratory gas conduit (54, 58; 154, 158) in such a way that, in the context of a predetermined first respiratory gas overpressure in the upstream respiratory gas conduit (54; 154) relative to the downstream respiratory gas conduit (58; 158), it permits an expiratory respiratory gas flow from the upstream respiratory gas conduit (54; 154) into the downstream respiratory gas conduit (58; 158); and in the context of a predetermined second respiratory gas overpressure in the downstream respiratory gas conduit (58; 158) relative to the upstream respiratory gas conduit (54; 154), it blocks a gas flow from the downstream respiratory gas conduit (58; 158) into the upstream respiratory gas conduit (54; 154),