A method for operating a breathing system (3) with a respiratory flow sensor (1), in which a wireless reader unit in (3) reads out the content of a storage unit for operating data for (3) which is connected with (1), so that the system (3) is only ready for operation after reading out the operating data, and the data also include identification and/or quality data of the sensor (1) for the system (3) which are compared with corresponding data stored in (3), so that (3) is only ready for operation when the data match one another. An independent claim is included for a device for operating a breathing system in which the system (3) is fitted with a read-out unit and preferably with a recorder (5) and a respiratory flow sensor (1) with an assigned, readable wireless device for the storage of operating data for the system (3), especially a transponder (2).
