Abstract: An external wound dressing retainer includes a frame having an opening substantially surrounded by the frame, wherein the opening is bounded by a plurality of edges, wherein the frame includes a first side and a second side including an adhesive for adherence to skin of a patient; a flap having a plurality of edges, wherein the dimensions of the flap substantially correspond to the dimensions of the opening, and the flap is attached to the frame via a corresponding edge of the flap and the frame; and a sealing mechanism for releasably engaging non-attached edges of the flap to corresponding non-attached edges of the frame. The sealing mechanism is a zipper arrangement that includes complementary interlocking first and second grooves situated on the non-attached edges of the flap and the frame, respectively, further comprising a sliding element adapted to sealably join the first groove to the second groove.