HUMIDITY CALCULATOR LAB-EL description

LAB-EL HUMIDITY CALCULATOR computer program was designed for basic calculation of humidity measurements. This kind of calculations are often required in meteorology, when designing air conditioning systems, during manufacturing processes as well as in laboratories (e.g. when calibrating measurement equipment). This program allows users to convert one set of humidity parameters into another.

LAB-EL HUMIDITY CALCULATOR computer program calculates uncertainty results. These are taken from uncertainty of input data (introduced by the user through the input window) and the uncertainty of formula used for moisture calculation.

The results are true with respect to over water or to over ice, depending on whether there is water or frost (ice) in the chilled mirror hygrometer or psychrometer.

The input and counted data values are as follow:
DP - dew point temperature,
FP - frost point temperature,
RH - relative humidity with respect to water (or to ice),
T - air temperature,
Tw/Ti - the wet-bulb (or ice-bulb) temperature in psychrometer,
P1 - air pressure at point 1, where input values are defined,
P2 - air pressure at point 2, where values are calculated,
PPMV - volume of water vapour in dry air (ppm, parts per million),
PPMW - mixing ratio, weight of water vapour in dry air (ppm, parts per million),
x - mixing ratio, weight of water vapour in dry air (g/kg),
I - enthalpy I(1+x) of mixture dry air (1) and water vapour (x),
WVP - vapour pressure in moist air,
SWVP - saturation vapour pressure of moist air with respect to water (or to ice).