A filter assembly for use in an electronics enclosure is disclosed herein. The filter assembly has an inner assembly having a filter material comprising fibrous media and a containment assembly having a first containment layer and a second containment layer. The containment assembly defines an outer perimeter and the first containment layer and a second containment layer are bonded along the outer perimeter in an outer weld area to encapsulate the inner assembly. The outer weld area extends between the outer perimeter and an interior perimeter. The inner assembly defines an inner assembly perimeter that is within the outer perimeter of the containment assembly.