The invention relates to a system (200) for cleaning workpieces (202, 204, 206), comprising a cleaning device, in particular a cleaning device (218, 240) for applying a cleaning fluid to a workpiece (204). In the system, a device (254) for detecting a (first) soiling state (S1), for example in the form of an initial soiling of a workpiece (204) before cleaning in the system, and/or a device (254) for detecting a (second) soiling state (S2), for example in the form of a residual soiling (S2) of a workpiece (208) cleaned in the system, are/is provided. The system (200) contains an assembly (130, 266) that determines a system operating state (A, B, C) and/or sets at least one process parameter (P) of a cleaning process in the system according to a first and/or second soiling state (S1, S2) detected for workpieces (108, 208).