The present invention pertains to a device for controlling a gaseous mixture comprised in a portable enclosure as well as an enclosure comprising such device and a monitoring system comprising at least one corresponding enclosure. Accordingly, a device (1) for controlling a gaseous mixture (2) comprised in a portable enclosure (10) is suggested, which comprises a gas delivery device (3) for the delivery of at least one gaseous component (20, 22) to the gaseous mixture (2) and/or a gas removal device (4) for the removal of at least one gaseous component (20, 22) from the gaseous mixture (2), a gas monitor device (5) configured to detect at least one parameter (50) relating to the gaseous mixture (2), and a control unit (6) in communication with the gas monitor device (5) to receive the detected parameter and configured to determine an information (60) relating to the gaseous mixture (2) based on the received parameter (50). Furthermore, the control unit (6) is configured to actuate the gas delivery device (3) and/or the gas removal device (4) based on the determined information (60) to control the amount of the gaseous component (20, 22) in the gaseous mixture (2).
