The volume flows through a double-layer polymeric membranous dressing, formed by three types of thermoplastic polymeric fibers called Textus Bioactiv were studied. The first layer contains two types of fibers: the polymeric fibers containing the hydrophobic core and hydrophilic surfaces with silver zeolite, and hydrophilic super absorbing polymers (SAP). The second layer of membrane comprises third type of polymeric fibers, arranged parallel to the skin surface, creating a net which prevents the membranous dressing against sticking to a treated wound. Using the Kedem-Katchalsky equations, the transport model of a double-layer membrane Textus Bioactiv and temporal and concentration characteristics of hydraulic permeability, coefficients of reflection and solute permeability were determined. It was found that the values of reflection and solute permeability coefficients are not dependent as well as time and concentration. Experimental results show that the polymeric membranous dressing contains the silver ions possessing nonlinear transport properties, which are the consequence of structure and physicochemical properties of polymeric membranes. The pressure characteristics of the volume flux were determined and it was stated that, the value of this flux is dependent on the value of the hydrostatic pressure difference (Delta P) and the concentration difference (Delta C) of solutions separated by the membrane. Experimental results show that the membranous dressing Textus Bioactiv possess the rectifying properties in relation to the volume flows. These properties occur above a threshold value of Delta C. (c) 2006 Elsevier B.V. All rights reserved.