Theory
Time allocation: 10 min.
Relative Humidity
Humidity is a fundamental property of air. Air humidity indicates how much water in gaseous form (water vapor) is contained in a given air volume. The amount of water vapor is highly variable over time and differs from place to place. From the perspective of meteorology and climatology, the amount of water vapor is crucial, as it affects the weather and local climate.
Relative humidity expresses the ratio between the current amount of water vapor in the air and the amount the air would hold at the same pressure and temperature when fully saturated. It is expressed as a percentage (%). Relative humidity is also sometimes referred to as proportional humidity.
The dew point is the temperature at which the air is fully saturated with water vapor (relative humidity reaches 100%)
Zdroj: https://en.wikipedia.org/wiki/Humidity#Relative_humidity
Effect of Humidity on Health
Air humidity in an apartment or house has a direct and significant impact on the quality of our living environment and, above all, on our health. Experts recommend that the ideal indoor humidity should range between 40% and 60%, depending on the type of room and how it is used—for example, in bathrooms or kitchens, higher humidity levels are expected..