The performance of duct systems suffer due to (1) air leakage at the duct/air terminal connections because of inadequate attention by designers, air terminal manufacturers, installers, sheet metal contractors, and TAB contractors, and (2) the disputed responsibility for effective connection of ducts to air terminals. If the leakage of unsealed, marginally sealed and effectively sealed connections were quantified and publicized, a reliable database would exist to prompt and possibly obligate manufacturers and designers to take appropriate action and leave little excuse for not properly sealing duct/air terminal connections.

The objectives of this research project are: 1) Fill voids in earlier investigations sponsored by ASHRAE. 2) Provide information that is not available in manufacturer’s air terminal rating and installation literature. 3) Enhance assessment of the accuracy of field (flow rate) TAB reports. 4) Supply data that will affect the energy consumption of HVAC systems, and the control of indoor air quality (room air motion and room ventilation effectiveness).