Patent ID: 7503844
Filing Date: 2009-03-17
Classification: F24F

Abstract:
1. A method of retrofitting a ventilation assembly used in security settings, comprising: providing an existing ventilation assembly having an existing fixed frame in which an existing opening having an existing venting area is defined and having at least one outer cross member spanning the existing venting area, an inner frame having an opening in which an inner venting area is defined and having at least one inner cross member spanning the existing venting opening, and a grille member positioned between the outer frame and the inner frame and generally aligned with each respective venting area; removing the at least one outer cross member of the existing outer frame, thereby providing access to the grille member; removing the existing grille member to provide access to the inner frame and inner cross member; removing a portion of the at least one inner cross member and leaving at least one remaining portion; providing a replacement outer frame having an opening that defines an open inner venting area not extending beyond the existing venting opening and being substantially free of obstructions; providing a replacement grille member; and attaching the replacement outer frame to the inner frame at one or more points positioned to have axes extending through the existing venting opening and over a remaining portion of the existing fixed frame with the replacement grille member positioned between the replacement outer frame and the inner frame.