These fire-rated rolling steel doors offer superior protection wherever a listed fire door is required. Common applications include factories, warehouses, mills, distribution centers and parking garages. Customized fire doors are available for conveyor openings. These doors feature fusible links mounted on both sides of the wall that separate to automatically close the door. UL recommends a 165º F (74º C) fuse link for ambient conditions for 100º F (38º C) or less, or a 212º F (100º C) fuse link for ambient conditions over 100º F (38º C).