Use the graph or tables below to determine the range of air leakage you can test with the Lynx 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.

25 mm Orifice Plate

System Static Pressure (pa)Min Leakage (cmh)Max Leakage with Lynx Tester (cmh)
2501555
5001550
7501545
10001540
12501530
15001520
2000150

50 mm Orifice Plate

System Static Pressure (Pa)Min Leakage (cmh)Max Leakage with Lynx Tester (cmh)
25055220
50055210
75055205
100055180
125055145
15005585
200055-

75 mm Orifice Plate

System Static Pressure (Pa)Min Leakage (cmh)Max Leakage with Lynx Tester (cmh)
250140595
500140580
750140545
1000140485
1250140390
1500140240
2000140-

100 mm Orifice Plate

System Static Pressure (Pa)Min Leakage (cmh)Max Leakage with Lynx Tester (cmh)
250295935
500295915
750295865
1000295775
1250295620
1500295390
2000295-

Min Leakage is the recommended minimum flow rate based on a 100 Pa pressure drop across the orifice plate. For example, approximately 140 cmh through the 75 mm orifice plate results in a 100 Pa, so 140 cmh is the recommended minimum leakage. Although it is possible to measure an orifice plate pressure differential lower than 100 Pa, the accuracy of the resulting flow rate is decreased. Unit of cmh is equal to cubic meters per hour.