Air is the first necessity of life. We may live without food for days and without water for hours; but we cannot live without air more than a few minutes. Our air supply is therefore of more importance than our water or food supply, and good ventilation becomes the first rule of hygiene.
Living and working rooms should be ventilated both before occupancy and while occupied.
It must be remembered that the mere construction of the proper kind of buildings does not insure ventilation. We may have model dwellings, with ideal window-space and ventilating apparatus, but unless these are actually used, we do not benefit thereby.
Features of Ventilation
The most important features of ventilation are motion, coolness, and the proper degree of humidity and freshness.
Drafts
There is an unreasonable prejudice against air in motion. A gentle draft is, as a matter of fact, one of the best friends which the seeker after health can have. Of course, a strong draft directed against some exposed part of the body, causing a local chill for a prolonged time, is not desirable; but a gentle draft, such as ordinarily occurs in good ventilation, is extremely wholesome.
Air and Catching Colds
It goes without saying that persons unaccustomed to ventilation, and consequently over-sensitive to drafts, should avoid over-exposure while they are in process of changing their habits. But after even a few days of enjoyment of air in motion, with cautious exposure to it, the likelihood of cold is greatly diminished; and persons who continue to make friends with moving air soon become almost immune to colds.
The popular idea that colds are derived from drafts is greatly exaggerated. A cold of any kind is usually a catarrhal disease of germ origin, to which a lowered vital resistance is a predisposing cause.