Block Iron & Supply (Madison) is a recognized member of Intertek's Certified Machiner Program, allowing them to modify Intertek Certified Fire Doors and Frames as detailed within the applicable Intertek specification listings. Block Iron & Supply (Madison) at 3121 Syene Road Madison, WI 53713 is subject to routine inspections to verify that modifications to Intertek Certified Fire Doors and Frames are done in compliance with the requirements of the Intertek specification listings.