Grease duct joints are held together by the use of fashioned V clamps and sealed with 3M Fire Barrier 2000+. Reduction in cross-section: The inner dimensions (width and height for rectangular ducts, diameter for circular ducts) of the smoke extracting ductwork shall not minimize by much more than ten% in https://johnnyjgatm.blogdemls.com/36836807/detailed-notes-on-fire-resisting-ductwork-insulation