EXAMPLE
:
If you have 183 cfm flow at 10" of water, multiply 183 by .707 and you find that you have 129.38 cfm at 5" of water.
183 x .707 = 129.38 cfm
Airflow Conversion Chart
Multipliers
If you want flow at:
If you have flow at:
3"
5"
7"
10"
12"
15"
20"
25"
28"
30"
35"
40"
45"
3"
1.00
1.29
1.53
1.82
2.00
2.24
2.58
2.89
3.05
3.16
3.42
3.65
3.87
5"
.774
1.00
1.18
1.41
1.55
1.73
2.00
2.24
2.37
2.45
2.65
2.83
3.00
7"
.655
.845
1.00
1.12
1.31
1.46
1.69
1.89
2.00
2.07
2.24
2.39
2.54
10"
.548
.707
.837
1.00
1.09
1.22
1.41
1.58
1.67
1.73
1.87
2.00
2.12
12"
.500
.645
.764
.913
1.00
1.12
1.29
1.44
1.53
1.58
1.71
1.83
1.94
15"
.447
.577
.683
.816
.894
1.00
1.15
1.29
1.37
1.41
1.53
1.63
1.73
20"
.387
.500
.592
.707
.774
.866
1.00
1.12
1.18
1.22
1.32
1.41
1.50
25"
.346
.447
.529
.632
.683
.775
.894
1.00
1.06
1.10
1.18
1.28
1.34
28"
.327
.422
.500
.598
.654
.732
.845
.945
1.00
1.04
1.12
1.20
1.27
30"
.318
.408
.483
.577
.632
.707
.816
.913
.966
1.00
1.08
1.15
1.22
35"
.293
.378
.447
.535
.586
.655
.756
.845
.894
.926
1.00
1.07
1.13
40"
.274
.354
.418
.500
.548
.612
.707
.791
.837
.866
.935
1.00
1.08
45"
.258
.333
.394
471
.516
.577
.667
745
.789
.816
.882
.943
1.00