Use the graph or tables below to determine the range of air leakage you can test with the Panther 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 Panther Tester (cfm)
2545
4540
6535
8530
10525
12515

2-inch Orifice Plate

System Static Pressure (in.wg.)Min Leakage (cfm)Max Leakage with Panther Tester (cfm)
225190
425170
625150
825130
1025100
122555

3-inch Orifice Plate

System Static Pressure (in.wg.)Min Leakage (cfm)Max Leakage with Panther Tester (cfm)
250390
450350
650310
850265
1050205
1250120

4-inch Orifice Plate

System Static Pressure (in.wg.)Min Leakage (cfm)Max Leakage with Panther Tester (cfm)
2105820
4105740
6105655
8105550
10105425
12105245

5-inch Orifice Plate

System Static Pressure (in.wg.)Min Leakage (cfm)Max Leakage with Panther Tester (cfm)
21901320
41901210
61901065
8190875
10190615
12190270

Min Leakage is the recommended minimum flow rate based on a 0.4 in.wg. pressure drop across the orifice plate. For example, approximately 50 cfm through the 3-inch orifice plate results in a 0.4 in.wg. so 50 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.