A seal assembly is provided for maintaining a pressure difference between an exterior and an interior of an object having an access hatch and an access hatch frame. The seal assembly has a seal retainer having an interior face oriented toward the interior of the object, an exterior face oriented toward the exterior of the object, a hatch-side face oriented toward the access hatch and extending from the interior face to the exterior face, and frame-side face oriented toward the access hatch frame and extending from the interior face to the exterior face. The seal assembly also has at least one sealing member mounted on either the interior face or the exterior face of the seal retainer and a plurality of conduits formed in the seal retainer and extending from the exterior face to the interior face. The plurality of conduits include at least one supply conduit located between either the hatch-side or frame-side face and the at least one sealing member and at least one return conduit located so that the at least one sealing member is positioned between the at least one supply conduit and the at least one return conduit.