R H table
 Relative Humidity table

(1) Dry Bulb Temperature
(2) Wet Bulb reads oC lower than Dry Bulb

(1) (2)
o  01  02  03  04  05  06  07  08  09  10 12 14 16 18 20
02 84 68 52 37 22 08                  
04 85 70  56 42 29 26 03                
06 86  73 60 47 34 22 11                
08 87 75  63 51 39 28 18  07              
10 88 76 65 54 44 33 23 14 04            
12 89 78 67  57 47 38 29  20 11 03          
14 89 79 69 60 51 42 33 25 17  09          
16 90  80 71 62 54 45 37 29 22  14          
18 91 81 73 64 56 48 41 33  26 19  06        
20 91  82 74 66 58 51 44 37 30 24 11        
22 91 83 75 68 60 53 46 40 34 27  16  05      
24 92 84 76 69 62 55 49 43 37 31 20  09      
26 92 85 77 70 64 57 51 45 39  34 23  14 04    
28 92  85 78 72 65 59 53 47 42 37 26 17 08    
30 93 86 79 73 67 61 55 49 44 39 29  20 12 04  
32 93 86  80 74 68 62 56 51 46 41 32 23 15  08  01
34 93 87  81 75 69 63 58 53 48 43 34 26 18 11 05
36 93  87 81 75  70 64 59 54 50 45 36 28 21 14 08
38 94 88 82 76 71 65 60 56 51 47 38 31 23 17 11
40 94 88 82 77 72 66 62 57 52 48 40 33 26 19 13
42 94 88 83 77 72 67 63 58 54 50 42 34 28 21 16
44 94 89 82 78 73 68 64 59 55 51 43 36 29 23 18

Using the table
Note the dry and wet bulb temperatures. Take the difference between the two. Under column (1) check the dry bulb temperature and then find the relative humidity under the appropriate column.

E.g.
In one measure the dry bulb temperature was 32oC and web bulb was 25oC. The difference between the two is 3oC and we see that the RH was  78%.

In another measure the dry bulb temperature was 28oC and web bulb was 17oC. The difference between the two is 11oC but see that there is no column for this difference. So we interpolate the values and get the RH to be  31.5% or rounding it to 32%.

 

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