Abstract: The subject invention encompasses a thermal processing furnace having an elongated cylindrical processing chamber surrounding a tower assembly capable of receiving one or more articles to be processed. A pedestal assembly supports the tower assembly and contains a quartz door thereon which is axially translatable relative to the processing chamber into an inserted position where the tower assembly is inserted into the processing chamber. A quartz flange located along the perimeter of an opening at the end of the processing chamber contacts the quartz door forming a quartz seal therewith when the pedestal assembly is moved into the inserted position. A scavenger cavity is located at the end of the chamber having the opening therein and is in fluid flow relationship with the contact area between the quartz flange and the quartz door forming a quartz seal. Gas from within the processing chamber which may leak through the quartz seal is captured by the scavenger cavity and evacuated by an evacuation means.