A device and method for generating a physical plasma in hoses of long and simultaneously constricted lumen, flexible or rigid dielectric hoses, tubes or other hollow bodies in the low, normal or overpressure range, which are partially or completely filled or flushed by process medium of gas or gas mixtures, one or more liquids, liquids including gas bubbles, liquid-gas mixtures, aerosols and/or foam, for purposes of cleaning, activating, coating, modifying and biologically decontaminating, disinfecting, sterilizing the inner walls of the hoses or the process medium itself. The device includes a high voltage supply and a process medium supply, at least one electrically conductive grounded electrode and at least one electrically conductive high voltage electrode, both embedded in the wall of the hose.
