Use the graph or tables below to determine the range of air leakage you can test with the Rhino using our standard orifice plates.

Note that the data is based on laboratory tests with short lengths of hard pipe attached to the duct leakage tester. Actual field performance will likely result in reduced performance due to: (1) amount of flexible duct used; (2) number of bends in flexible duct; (3) size of duct system; (4) line voltage. To account for flexible duct and 90 degree bends, use our program that takes these in-line losses into account.

1-inch Orifice Plate

System Static Pressure (in.wg.)Min Leakage (cfm)Max Leakage with Rhino Tester (cfm)
2945
4941
6938
8935
10930
12925
14919
16913

2-inch Orifice Plate

System Static Pressure (in.wg.)Min Leakage (cfm)Max Leakage with Rhino Tester (cfm)
237185
437165
637155
837140
1037120
1237100
143775
163755

3-inch Orifice Plate

System Static Pressure (in.wg.)Min Leakage (cfm)Max Leakage with Rhino Tester (cfm)
285410
485375
685350
850310
1085270
1285220
1485170
1685120

4-inch Orifice Plate

System Static Pressure (in.wg.)Min Leakage (cfm)Max Leakage with Rhino Tester (cfm)
2160785
4160720
6160660
8160590
10160515
12160415
14160325
16160225

5-inch Orifice Plate

System Static Pressure (in.wg.)Min Leakage (cfm)Max Leakage with Rhino Tester (cfm)
22601185
42601100
62601010
8260905
10260805
12260660
14260510
16260365

6-inch Orifice Plate

System Static Pressure (in.wg.)Min Leakage (cfm)Max Leakage with Rhino Tester (cfm)
24551550
44551420
64551330
84551185
104551035
12455895
14455660
16455480

Min Leakage is the recommended minimum flow rate based on a 0.4 in.wg. pressure drop across the orifice plate. For example, approximately 85 cfm through the 3-inch orifice plate results in a 0.4 in.wg. so 85 cfm is the recommended minimum leakage. Although it is possible to measure an orifice plate pressure differential lower than 0.4 in.wg., the accuracy of the resulting flow rate is decreased.