Control device for lowering the inspiratory positive air pressure (IPAP) to an EPAP or PEEP level, which comprises the following: a controllable breathing gas source in order to provide an IPAP pressure - sensor means in order to determine the pressure and/or flow values of the breathing gas - processor means to process the values determined by the sensor - storage means for retrievable provision of functions - input means (2, 8) in order to at least partially define the functions - control means which control the breathing gas source according to the functions, wherein the control means is configured such that same on the basis of the IPAP pressure in a first phase cause a pressure drop of a first characteristic in the breathing gas source, with a pressure drop in the region of 30 - 300 hPa/sec, and then in a second phase cause a second pressure drop (15, 16) in the breathing gas source, said second pressure drop comprising a characteristic which deviates from the first phase, wherein the second pressure drop lies at least in some sections in the region smaller than 30 hPa/sec, characterised in that when the second function has finished, a third function is applied which controls a pressure drop that is faster than the second function. a controllable breathing gas source in order to provide an IPAP pressure - sensor means in order to determine the pressure and/or flow values of the breathing gas - processor means to process the values determined by the sensor - storage means for retrievable provision of functions - input means (2, 8) in order to at least partially define the functions - control means which control the breathing gas source according to the functions, wherein the control means is configured such that same on the basis of the IPAP pressure in a first phase cause a pressure drop of a first characteristic in the breathing gas source, with a pressure drop in the region of 30 - 300 hPa/sec, and then in a second phase cause a second pressure drop (15, 16) in the breathing gas source, said second pressure drop comprising a characteristic which deviates from the first phase, wherein the second pressure drop lies at least in some sections in the region smaller than 30 hPa/sec, characterised in that when the second function has finished, a third function is applied which controls a pressure drop that is faster than the second function. - sensor means in order to determine the pressure and/or flow values of the breathing gas - processor means to process the values determined by the sensor - storage means for retrievable provision of functions - input means (2, 8) in order to at least partially define the functions - control means which control the breathing gas source according to the functions, wherein the control means is configured such that same on the basis of the IPAP pressure in a first phase cause a pressure drop of a first characteristic in the breathing gas source, with a pressure drop in the region of 30 - 300 hPa/sec, and then in a second phase cause a second pressure drop (15, 16) in the breathing gas source, said second pressure drop comprising a characteristic which deviates from the first phase, wherein the second pressure drop lies at least in some sections in the region smaller than 30 hPa/sec, characterised in that when the second function has finished, a third function is applied which controls a pressure drop that is faster than the second function.