Halton offers a variety of means for determining the exhaust flow. A Test and Balancing (TAB) port is integrated into all Capture Jet hoods. These ports are to be used in determining both the exhaust and Capture Jet air flows. Each incremental size of hood has been tested through the design range of air flows, and a curve has been generated showing airflow as a function of pressure drop across the TAB™ ports to provide an accurate reading of airf low.