The most important indicators that determine environmental conditions are temperature and humidity.
Every household today has a thermometer to measure temperature, and before going outdoors, we always check the thermometer to choose the right clothes. But although it is as important to know the humidity level as the temperature, hygrometers have not become popular among the population.
Usually, they can be found only in specialized laboratories or at weather stations. Meanwhile, this is a very useful device, which is useful to each of us in everyday life.
What is a hygrometer?
As already mentioned, a hygrometer is a device that measures moisture content in the atmosphere. Depending on its location, it can show how much moisture is in the room or outdoors, in the basement, the pantry, or even in your closet.
Hygrometers of various designs can show the percentage of moisture in the air or the absolute amount of water vapor in a cubic meter of the air mass. Professional, highly specialized instruments show the absolute moisture content, while household and general-purpose instruments show the percentage of humidity.
Scientists have been measuring air humidity for the past several centuries. The credit for the invention of the hygrometer belongs to the French naturalist and mechanic Guillaume Amonton, who made the first device in 1677.
The simplest hygrometer uses the property of human hair to change its length with changes in humidity. Degreased hair is attached to a frame and one end is attached to the hand of the instrument.
As the humidity changes, the hair stretches or loosens, deflecting the pointer to different positions along the scale. Instead of hair, pine chips can be used, which twist or straighten when humidity fluctuates.
Film hygrometers work similarly. A thin film of moisture-sensitive material stretches as the humidity increases and contracts as the humidity decreases. Changing the position of the film causes an arrow attached to it to deflect, which shows the humidity on a graduated scale.
An electrolytic hygrometer uses lithium chloride’s property of absorbing atmospheric moisture to measure humidity. As the concentration of the saline solution changes, so does its electrical resistance, which is reflected in the hygrometer readings.
It is desirable to use such a device only in room conditions, in a more or less stable temperature regime. At significant temperature fluctuations, the readings will not be highly accurate.
The principle of operation of the condensing hygrometer is based on the deposition of water vapor on the surface of the cooled metal mirror. The temperature required for condensation to occur is recorded: the lower it is, the drier the air is.
Measurements are usually made with semiconductor measuring elements – this is one of the most modern and accurate designs available for domestic use.
What is a hygrometer for?
Information about the level of humidity in the air may be needed in a variety of cases. Too humid, the air in the apartment leads to the growth of colds, as well as the appearance of stains on the walls and ceiling fungus that destroys building and finishing materials.
But too dry air is also bad for health, because it dries the mucous membrane of the throat and nasopharynx, depriving it of its protective properties.
If in summer the air humidity in the apartment is regulated naturally by opening window shutters, in winter problems often arise with this. Knowing the index of air humidity, it is much easier to avoid deviations from the norm.
This can be very important, especially if young children, the elderly, or those with asthma, bronchitis, or cardiovascular disease live in the home.
Monitoring humidity levels are important in many other cases as well – for example, for those who want to keep vegetables in the cellar over the winter until the next harvest. High humidity in the cellar will cause vegetables to rot, and too dry air will make them sluggish and unfit for food.
This is especially important for farms that not only grow agricultural products for their own needs but also sell them to the public.
Compliance with certain parameters of humidity can be important in a variety of areas: construction, the food industry, greenhouse, medicine, utilities, schools, and pre-school children’s institutions, etc.
Once you get into the habit of controlling humidity levels, you are sure to soon notice improvements in all areas of your life, from your health to your financial well-being.