TM 5-3610-259-14
l Check water level in cistern.
l Use eyedropper to add water to saturate wick and fill
cistern.
l Allow 5 minutes to lapse before recording wet and dry bulb
readings.
l Convert wet and dry bulb thermometer readings to relative
humidity as follows:
Air Temperature (dry bulb): 68°F
wet bulb:
62°F
Depression = dry bulb (t) - wet bulb (t1) = 68°F - 62°F =
6°F
Depression = 6°F
Use left column (Table 1-2) to find air temperature of
68°F.
Use top column (Table 1-2) to find depression of 6°F.
The intersection of both columns gives the percent of
relative humidity, in this case 71%.
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