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Equivalent Moisture Content Table
Relative Humidity Ambient Air Temperature - degrees Celsius and Fahrenheit
   
C: -1.1 4.4 10.0 15.6 21.1 26.7 32.2 37.8 43.3 48.9 54.4 60.0 65.6 71.1 76.7 82.2 87.8 93.3
F: 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200
5   1.4 1.4 1.4 1.3 1.3 1.3 1.2 1.2 1.1 1.1 1.0 0.9 0.9 0.8 0.7 0.7 0.6 0.5
10   2.6 2.6 2.6 2.5 2.5 2.4 2.3 2.3 2.2 2.1 2.0 1.9 1.8 1.6 1.5 1.4 1.3 1.1
15   3.7 3.7 3.6 3.6 3.5 3.5 3.4 3.3 3.2 3.0 2.9 2.8 2.6 2.4 2.3 2.1 1.9 1.7
20   4.6 4.6 4.6 4.6 4.5 4.4 4.3 4.2 4.0 3.9 3.7 3.6 3.4 3.2 3.0 2.8 2.6 2.4
25   5.5 5.5 5.5 5.4 5.4 5.3 5.1 5.0 4.9 4.7 4.5 4.3 4.1 3.9 3.7 3.5 3.2 3.0
30   6.3 6.3 6.3 6.2 6.2 6.1 5.9 5.8 5.6 5.4 5.2 5.0 4.8 4.6 4.3 4.1 3.8 3.5
35   7.1 7.1 7.1 7.0 6.9 6.8 6.7 6.5 6.3 6.1 5.9 5.7 5.5 5.2 4.9 4.7 4.4 4.1
40   7.9 7.9 7.9 7.8 7.7 7.6 7.4 7.2 7.0 6.8 6.6 6.3 6.1 5.8 5.6 5.3 5.0 4.6
45   8.7 8.7 8.7 8.6 8.5 8.3 8.1 7.9 7.7 7.5 7.2 7.0 6.7 6.4 6.2 5.9 5.5 5.2
50   9.5 9.5 9.5 9.4 9.2 9.1 8.9 8.7 8.4 8.2 7.9 7.7 7.4 7.1 6.8 6.5 6.1 5.8
55   10.4 10.4 10.3 10.2 10.1 9.9 9.7 9.5 9.2 8.9 8.7 8.4 8.1 7.8 7.4 7.1 6.8 6.4
60   11.3 11.3 11.2 11.1 11.0 10.8 10.5 10.3 10.0 9.7 9.4 9.1 8.8 8.5 8.2 7.8 7.5 7.1
65   12.4 12.3 12.3 12.1 12.0 11.7 11.5 11.2 11.0 10.6 10.3 10.0 9.7 9.3 9.0 8.6 8.2 7.8
70   13.5 13.5 13.4 13.3 13.1 12.9 12.6 12.3 12.0 11.7 11.3 11.0 10.6 10.3 9.9 9.5 9.1 8.7
75   14.9 14.9 14.8 14.6 14.4 14.2 13.9 13.6 13.2 12.9 12.5 12.1 11.8 11.4 11.0 10.5 10.1 9.7
80   16.5 16.5 16.4 16.2 16.0 15.7 15.4 15.1 14.7 14.4 14.0 13.6 13.1 12.7 12.3 11.8 11.4 10.9
85   18.5 18.5 18.4 18.2 17.9 17.7 17.3 17.0 16.6 16.2 15.8 15.3 14.9 14.4 14.0 13.5 13.0 12.5
90   21.0 21.0 20.9 20.7 20.5 20.2 19.8 19.5 19.1 18.6 18.2 17.7 17.2 16.7 16.2 15.7 15.1 14.6
95   24.3 24.3 24.3 24.1 23.9 23.6 23.3 22.9 22.4 22.0 21.5 21.0 20.4 19.9 19.3 18.7 18.1 17.5
EMC Equation
-The values in this table are calculated using the following formula: M = 1800/W [ Kh/(1-Kh) + (K1Kh + 2K1K2K2h2) / (1 + K1Kh + K1K2K2h2) ]
--where M = moisture content (%) W = 330 + 0.452T + 0.00415T2  
  T = temperature (oF) K = 0.791 + 0.000463T - 0.000000844T2  
  h = relative humidity(%/100) K1 = 6.34 + 0.000775T - 0.0000935T2  
  K2 = 1.09 + 0.0284T - 0.0000904T2  
Source: U.S. Forest Products Laboratory, General Technical Report 113