Very important when considering 13R in residential buildings utilizing subducts for kitchen, clothes dryer, bathroom and toilet exhaust..........
2009 IBC 716.5.3 Shaft enclosures (pg 119) (EMPHASIS IN CAPS) Shaft enclosures that are permitted to be penetrated by ducts and air transfer openings shall be protected with approved fire and smoke dampers installed in accordance with their listing. In Group B and R occupancies equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1, smoke dampers are not required at penetrations of shafts where: (Note reference to 903.3.1.1 - NFPA-13 !) 2.1. Kitchen, clothes dryer, bathroom and toilet room exhaust openings are installed with steel exhaust subducts, having a minimum wall thickness of 0.187-inch (0.4712 mm) (No. 26 gage); 2.2. The subducts extend at least 22 inches (559 mm) vertically; and 2.3. An exhaust fan is installed at the upper terminus of the shaft that is powered continuously in accordance with the provisions of Section 909.11, so as to maintain a continuous upward airflow to the outside. 5. Fire dampers and combination fire/smoke dampers are not required in kitchen and clothes dryer exhaust systems when installed in accordance with the International Mechanical Code. (Rigid metal ductwork shall be installed within the shaft to convey the exhaust.- No Subducts) John Drucker _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
