Abstract: A method for managing access to a confined space which is cooled by the direct injection of a cryogenic fluid, comprising at least one system for closing the confined space, which can prevent access to said confined space and can be opened/closed to a variable and controllable degree, and a data acquisition and processing device. The device can: control the open or closed state of the closure system; set and control the degree to which the closure system is open/closed; ensure that a time delay (TP) is respected every time the closure system is closed, after which time delay the injection of cryogenic fluid into the space resumes; and, at the request of a user, implement the cycle for opening the closure system. The device determines the time that has elapsed (TE) in the closed position since the last closure cycle of the closure system and compares TE to TP. If TE=TP the device immediately authorizes the opening of the closure system.