SG Industries is a recognized member of Intertek's Certified Machiners Program, allowing them to modify Intertek Certified Fire Doors and Frames as detailed within the applicable Intertek specification listings SG Industrie’s site 965 Detroit Ave Unit B, Concord, CA 94518 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.