The guideline describes hygrometric and psychrometric methods with which the water vapor content of the air (air humidity) can be determined. These are not absolute measurements, so the moisture measurements must be determined from the primary measured variables (e.g. temperature) through suitable calibration.*www.vdi.de/3786
VDI 3786 Blatt 4-1985 Referenced Document
DIN 50010-2:1981 Climates and their technical application; climatological terms and definitions; physical terms and definitions
DIN 58660:1966 Meteorological instruments - Thermometer 370 for psychrometer
DIN 58661:1966 Meteorological instruments - Thermometer 280 for psychrometer
VDI 3786 Blatt 3-1985 Meteorological measurements concerning questions of air pollution; air temperature