Humidity and the effects of dry air

Apart from temperature and air purity, the third important factor in the maintenance of an ideal room climate is the moisture content of the air. Whilst the danger of excessive humidity in our latitudes is comparatively low, often, during the winter months when rooms are heated, we experience excessively dry air indoors. The consequences of dry air are severe.

Opening the windows will not help to avoid dry room air during the cold season. Instead, it is necessary actively to add moisture to the air. Because just like people, the air becomes thirsty too. The art lies in giving the air just enough water to drink so that it reaches the ideal moisture content level. If moisture is not added to the air artificially, it will try to quench its thirst by taking the moisture from our skin, mucous membranes, plants, wooden furniture, etc.

The moisture content level of the air is measurable using an instrument known as a hygrometer (Hygro = Water). The reading given by a hygrometer is called "relative air humidity".

Medical experts recommend a relative air humidity of between 40 and 60 per cent. At these levels, our senses tell us that the air in the room is ideally humidified. Then it is also ideal for our health, for the animals and plants in the room, for furniture, instruments and much more besides.

Dry air has many nasty effects:

Discomfort, tiredness, sickness
Breathing in dry air makes the uptake of oxygen and its subsequent transfer to the blood system more difficult. Fatigue, tiredness and reduced concentration levels are symptoms of a reduced oxygen supply.

Increased susceptibility to colds
The self-cleansing function of the windpipe is affected by dry air. The consequences: increased susceptibility to infections and respiratory tract complaints.

Dry skin
Low relative humidity results in greater loss of moisture from the skin's outer layers. It becomes dry, rough and flaky, and has a tendency to become inflamed.

Increased levels of dust
Humidity binds dust. Dry room air causes dust to rise. This is made worse by the thermal currents created by the radiators.

Increased static electricity
Particularly in textiles.

Damage to wooden objects
Furniture and other wooden objects have a dull surface in dry room air. They dry out and eventually cracks will appear.

Out of tune musical instruments
Low moisture content in room air will cause musical instruments to go out of tune.