b'NCTL Fact SheetClass/Design Class/Design Structural Test Structural Test Water Test Water TestPressure in Pressure Pressure in Pressure Pressure in PressurePSFEquivalent PSF Equivalent PSF Equivalent(inches of water) Wind Velocity (inches of water) Wind Velocity (inches of water) Wind Velocityin MPHin MPHin MPH 15 (2.88) 77.52 22.50 (4.32) 94.94 2.86 (0.55) 24.6720 (3.84) 89.51 30.00 (5.76) 109.63 3.00 (0.58) 33.8525 (4.80) 100.08 37.50 (7.20) 122.57 3.75 (0.72) 38.7630 (5.76) 109.63 45.00 (8.64) 134.27 4.50 (0.86) 42.4635 (6.72) 118.42 52.50 (10.08) 145.03 5.25 (1.01) 45.8640 (7.68) 126.59 60.00 (11.52) 155.04 6.00 (1.15) 49.0345 (8.64) 134.27 67.50 (12.96) 164.45 6.75 (1.30) 5250 (9.60) 141.53 75.00 (14.40) 173.34 7.50 (1.44) 54.8255 (10.56) 148.44 82.50 (15.84) 181.8 8.25 (1.58) 57.4960 (11.52) 155.04 90.00 (17.28) 189.89 9.00 (1.73) 60.0565 (12.48) 161.37 97.50 (18.72) 197.64 9.75 (1.87) 62.570 (13.44) 167.47 105.00 (20.16) 205.1 10.50 (2.02) 64.8675 (14.40) 173.34 112.50 (21.60) 212.3 11.25 (2.16) 67.1480 (15.36) 179.03 120.00 (23.04) 219.26 12.00 (2.30) 69.3485 (16.32) 184.54 127.50 (24.48) 226.01 12.00 (2.30) 69.3490 (17.28) 189.89 135.00 (25.92) 232.56 12.00 (2.30) 69.3495 (18.24) 195.09 142.50 (27.36) 238.94 12.00 (2.30) 69.34100 (19.20) 200.16 150.00 (28.80) 245.14 12.00 (2.30) 69.34Air Inflitration Pressure in PSFEquivalent Wind Velocity in MPH(inches of water)1.57 (0.30) 25.086.24 (1.20) 50.00These values are calculated from the Ensewiler Formulat, P= 0.00256 V^2, where V = Wind Velocity in MPH and P = theDifferential Pressure across the window in Pounds per Square Foot (PSF).The equation assumes the direction of wind isperpendicular to the window and there are no effects from surrounding terrain or the shape of the building in which it isinstalled.Positive (+) pressures act inward and Negative (-) pressures act outward on the window. An easier way to perform this calculation would be as follows: Square Root of PSF x 20.016 (e.g. 15 Sq.Rt. = 3.87 x 20.016 = 77.52)19'