Grease duct joints are held together through fashioned V clamps and sealed with 3M Fire Barrier 2000+. Reduction in cross-portion: The inner dimensions (width and height for rectangular ducts, diameter for circular ducts) with the smoke extracting ductwork shall not decrease by over 10% throughout the check. Integrity (E): Integrity https://grease-tight-extract-duct46778.thechapblog.com/35958319/grease-tight-extract-ductwork-an-overview