The present specification relates to an air treatment device and a detachable sensor module. The air treatment device comprises a user interface configured to display, for selection by a user, at least one static or open-loop operational mode to be executed by a controller; and a wall comprising one or more pervious sections towards an ambient volume. One side of the wall comprises a connector for mating with a corresponding connector of the detachable sensor module, and the connector, when the sensor module is present, enables a data connection from the sensor module to the controller. When the data connection is enabled, the user interface is configured to display at least one closed-loop operational mode, in which the controller controls the air treatment section in response to measurement data relating to the ambient volume received from the sensor module.