In a method for preparing decontamination measures within a room (1) located in a building and used by people (19), in a planning acquisition step, on the basis of a specified use concept, a plurality of regions of use (7, 9) within the room (1) is identified, and for each region of use (7, 9) an expected use intensity is determined on the basis of previously determined parameters. In a subsequent planning implementation step, for each region of use (7, 9), proceeding from the expected use intensity, a suction means (20, 21) assigned to said region of use (7, 9) and having an associated supply air volume flow is specified. In a method by carrying out the decontamination measures, while the decontamination measures are being carried out, operation of individual suction means (20, 21) is adjusted to an actual use of the assigned region of use (7, 9) by people (19), and a suction volume flow suctioned by the suction means (20, 21) in question is specified, between a minimum value specified for the suction means (20, 21) in question, and a maximum value.