Many owners of houses or apartments sometimes forget that the optimal state of indoor air humidity is as integral a component of comfortable living conditions as, say, temperature. Perhaps the dependence is not so obvious, but both excess and insufficient humidity have an extremely negative impact on the health of household members.
A device for measuring indoor air humidity
How to control this parameter? It’s very simple - purchase and install a device for measuring indoor air humidity. You can do without the device, in principle, completely simulating its operation using improvised means. Or even use the simplest “folk methods”. All this will be discussed in this publication.
What is air humidity
Humidity
is a measure of the amount of water vapor in the air. The humidity of home air changes depending on weather conditions and human life processes.
A decrease in indoor humidity can occur due to excessive use of heating devices or air conditioning. Cooking without a hood or high-quality ventilation, drying clothes in the house, and high humidity outside lead to a high level of humidity in the apartment.
Dry indoor air can cause drying of furniture and finishing materials, wilting of plants, dry skin and mucous membranes. Dry air often leads to allergic reactions and the development of colds.
Too humid air can also damage furniture and finishing materials, contribute to the development of fungus on the walls and reduce human immunity. An unpleasant damp smell may appear in the apartment.
Criterias of choice
In order to choose a quality device, study the following parameters:
- Hygrometer designs: psychrometric type, mechanical devices and electronic devices.
- Measuring range. Since humidity levels in residential premises decrease significantly during the winter season, you need a device capable of measuring in the range of 20.0-70.0%; in wet rooms - bathhouses, basements, you will need a device with a scale of up to 100.0%.
- Accuracy. For household measurements, a device with a division of up to 2-3% is sufficient, for more accurate ones up to 1%. This level can only be provided by an electronic device or psychrometer.
- Design. For many buyers it has special significance; for a bathhouse it is usually a model with a wood or stone finish, in the living room plastic products are harmonious, and for children's rooms an ideal option is made in the form of a toy.
Thus, we can summarize that a hygrometer is a very important and inexpensive device for household use, which helps to timely establish the actual humidity, both indoors and outdoors, so that the user can promptly protect himself and his loved ones from the harmful effects of excessively humid, and dry air.
How is air humidity measured?
Without special equipment, it is difficult to determine the relative exact level of air humidity. However, moisture concentrations that do not meet the norm can be determined by dry skin and mucous membranes or the accumulation of condensation (dew point) on windows and mirror surfaces.
Relative humidity
— the content of water vapor in the air and its interaction with air temperature.
Today there are special devices with which you can determine the balance of air humidity in a room with high accuracy.
Condensation hygrometer
Let's consider the design and operating principle of a condensation hygrometer (Figure 1). It can be used to determine the absolute humidity of the air based on the dew point.
Figure 1. Condensation hygrometer design
It is based on a small metal box 1 . Its front wall 2 is surrounded by a ring 3 . The surfaces of these elements are well polished. 4 is placed between them . 5 is attached to the box itself . 6 is inserted inside the box .
Let's fill the box, for example, with ether. You already know that this liquid evaporates quite quickly. Let's start blowing air through the box using a blower. This way we will speed up the evaporation of the ether, the box will quickly cool down. Soon droplets of dew will appear on the polished surface.
Let us note the temperature that is currently observed. This is how we determined the dew point . It was at this point that the steam became saturated .
Next, using special tables, you can determine the absolute humidity of the air.
A typical laboratory hygrometer is shown in Figure 2.
Figure 2. Laboratory hygrometer
Instruments for measuring air humidity
A device for measuring air humidity is called a hygrometer
.
Hygrometer
is a device that measures indoor air humidity. If the percentage of moisture in the air is too low, various viruses can enter the body, which can significantly weaken the immune system. Thanks to the hygrometer, you can avoid discomfort and protect the mucous membranes and skin from drying out.
According to GOST, a comfortable level of relative humidity in a room in winter is 30–45%, in warm months — 30–60%.
Principle of operation
of this device is based on the physical characteristics of the materials of which it is composed. Materials, depending on the level of moisture in the air, change properties: weight, density, length and others.
There are several types of hygrometer:
- hair,
- film,
- weight,
- condensation,
- psychrometric,
- electronic.
Hair hygrometer
Hair measuring device
consists of degreased synthetic hair, pointer, spring and scale. When the amount of vapor in the air changes, the tension in the hair changes and the spring reacts to these changes by changing the position of the needle on the scale. The humidity determination range of a hair hygrometer is from 30 to 80%.
Now you can find many models of hygrometers, among which there are classic humidity meters with a temperature column, and electronic ones, the display of which immediately displays all the indicators of the optimal microclimate in the house.
Film hygrometer
The sensitive element here is a film, which also contracts or stretches when the humidity level changes. This sets the counterweight in motion, which changes the angle of the needle on the scale. The operating range is also from 30 to 80%.
Weight and condensation hygrometers
Weighing mechanical and condensation hygrometer
are distinguished by high accuracy of measuring the level of humidity in the room, since both are devices for measuring absolute air humidity. Such equipment is used only in laboratories, but not for measuring the humidity of home air.
Absolute air humidity is a measure of the amount of water vapor in the atmospheric air.
Psychrometric hygrometer
The psychrometer is based on the interaction between “dry” and “wet” thermometers. The device contains two thermometers with tinted liquids (red and blue). One of these tubes is wrapped in cotton cloth, the end of which is immersed in a reservoir of solution. The fabric becomes wet, and then the moisture begins to evaporate, thereby cooling the “wet” bulb. The lower the air humidity in the room, the lower the thermometer readings will be.
To calculate the percentage of air humidity on a psychrometer, you should find the air temperature value in the table on the device according to the thermometer readings and find the difference in values at the intersection of the indicators.
There are several types of psychrometers:
- stationary.
Includes two thermometers (dry and wet). It works according to the principle described above. The percentage of air humidity is calculated according to the table. - aspiration.
It differs from a stationary one only in the presence of a special fan, which serves to blow the thermometers with an incoming air flow, thereby speeding up the process of measuring air humidity. - remote.
This psychrometer comes in two types: manometric and electrical. Instead of mercury or alcohol thermometers, it has silicon sensors. However, as in the first two cases, one of the sensors remains dry, the second remains wet.
Electronic hygrometer (digital)
Also known as home digital weather stations. The operating principle of digital hygrometers is based on constant measurement of the air condition in the room. The device operates from the mains or a household battery. Inside the hygrometer there is a sensor that records changes in the moisture concentration in the room air.
All calculations are displayed on the device display, information is updated in real time.
Hair hygrometer
From the name of this device you can guess that there is hair somewhere in its device. And, indeed, the action of the hair hygrometer (Figure 3) is based on one interesting property of human hair. The fact is that as the relative humidity of the air increases, the hair lengthens.
Figure 3. Hair hygrometer
The scale of this device already shows the relative humidity values. When relative humidity increases, hair lengthens, and when relative humidity decreases, it shortens. In this case, the arrow moves along the scale, indicating the value of relative air humidity.
How to choose an air humidity meter
Modern electronic hygrometers are safe and compact. The accuracy of air humidity measurement has virtually no errors, which means this is one of the most suitable options for an apartment.
There are many models that differ in functionality, design, size, etc.
To choose a hygrometer for your apartment, you need to consider several points.
Advantages of the device
- First of all, you should pay attention to the speed of issuing results and the coefficient of error of readings;
- hygrometers can combine several devices at once: thermometer, clock, alarm clock, dew point meter, calendar, barometer, atmospheric pressure level, have voice guidance and other capabilities. If a humidity meter performs several functions at the same time, it is called a stationary home weather station;
- some modern hygrometer models have a Wi-Fi module for displaying information about the weather in the region;
- There are also remote models that can easily be moved from room to room or even outside to measure air humidity.
Humidity range and heating threshold
The range of air humidity depends on the purpose of the room. Eg:
- in the bedroom and living room these figures can vary from 20 to 80%;
- in the kitchen, near the balcony and in the pantry - from 10 to 90%;
- In the bathroom, the humidity level can reach 100%, especially after taking a bath or shower.
The wider the range of operating values of a device, the higher its price. Before purchasing a hygrometer, you should consider where it will be located, and hence choose the operating range.
The heating threshold is important for devices installed in a bathhouse or sauna. In this case, the operating temperature should not be lower than 120 °C.
Measurement accuracy
This indicator is also important, but there are no devices with large discrepancies in readings on the Russian market, and maximum accuracy with minimal errors is needed only for maintenance, for example, a home wine library.
Recommendations for choosing a hygrometer
Modern hygrometers differ not only in functionality, but also in size, price and measurement accuracy.
Standard humidity is considered to be between 40 and 60%. Humidifiers or dehumidifiers can be used to create optimal indoor conditions.
The most optimal type of devices are considered to be digital devices, for the use of which you do not need to make any calculations or have any professional skills.
Such a hygrometer should be selected based on the following criteria:
- manufacturer's permissible measurement error;
- width of the range of operating values;
- heating threshold if the device is planned to be used in saunas or baths;
- speed of calculation of results;
- compactness and mobility;
- the presence of additional options - clock, calendar, alarm clock, barometer, built-in Wi-fi module and others;
- price category and manufacturer.
Before purchasing a hygrometer, you should carefully study not only the characteristics of devices offered on the market, but also reviews from customers who have already tested the device in action.
By purchasing a high-quality hygrometer, you can be confident in the accuracy of relative humidity measurements. However, a number of related questions arise about how to normalize the microclimate and what methods and devices to use to normalize indicators.
How to maintain relative humidity in your home
We have already decided how to measure the humidity level in the room; now we just need to figure out how to restore the optimal humidity level.
If the humidity is low
- Ventilate the room.
However, this method cannot always significantly improve the state of the home microclimate, since in the summer the street air can be dry.
Also, when ventilating in the traditional way, dangerous microbes, allergens, dust, harmful gases and unpleasant odors can enter the apartment. But if you keep the windows constantly closed, then there is a high probability of encountering another problem in maintaining the microclimate - stuffiness (high levels of carbon dioxide).
High-quality ventilation is also important when ventilating rooms. A valve can provide fresh air into the room, but it will not be enough to ventilate a room inhabited by more than one person. The air passing through the supply and exhaust valve is not heated and not cleaned.
A breather will help you easily deal with the stuffiness and not let dangerous “guests” from the street into your house. This is a supply ventilation device that takes air from the street, heats it, cleans it and supplies it to the room.
- Regularly wet clean
rooms. - Install an aquarium at home.
Keeping fish in an aquarium at home can also affect air humidity. But remember that you need to take care of the fish and keep the aquarium clean. - water containers
on window sills or near heating radiators . - A humidifier
is a good option for your home. This device will cope with dry home air, improve the microclimate and prevent the development of respiratory diseases. - Climate control equipment (air conditioner, breather, air purifier, Danfoss Eco thermostat)
complete with a MagicAir base station will help not only track the microclimate conditions in the house, but also maintain optimal performance.
The base station collects information from room air about temperature, humidity and carbon dioxide concentration. All indicators are displayed on the smartphone screen in the MagicAir application.
Psychrometer
The psychrometer (from the Latin psychros - cold, metrio - to measure) is presented in Figure 4.
Figure 4. Psychrometer
This device consists of two thermometers. The end of one of them is wrapped in cloth and lowered into water. The water evaporates and the thermometer cools. Thermometers will show different values.
Evaporation occurs less intensely at high relative humidity, and more intensely at low relative humidity. To evaluate it, you need to record the temperature difference on thermometers. There are also special tables for them, from which you can find out the relative humidity.
Briefly about the main thing
An air humidity measuring device is necessary in order to monitor the indicator and avoid problems associated with dryness or dampness in the room.
Manufacturers produce different versions of equipment, differing in materials of manufacture and measurement features.
- The most understandable operating principle is for devices that operate on the basis of hair and film. Weighing and condensing devices are preferred by scientists.
- The psychrometer has a complex design and is considered one of the most accurate instruments.
- Electronic devices will show accurate data in a short time.
- Home weather stations combine a barometer and a hygrometer and have Internet access.
When choosing, you should take into account the installation location, technical parameters, on which the cost of the equipment depends.
Home weather stations for convenient microclimate control
For consumers who pay increased attention to their own health and strive to bring air parameters closer to the optimal value, climate control equipment manufacturers offer to buy an electronic hygrometer - a humidity and temperature meter and a barometer in one device. A design with similar functionality is capable of fully controlling the microclimate. However, the price of such devices is quite high.
Such devices not only have a large number of functions, but also have a decorative design. They can optimally fit into almost any room interior. You can also find unusual combinations on sale, for example, baby monitors with a built-in hygrometer. These devices are optimized specifically for children's rooms. There are also models with Wi-Fi function. They connect to the World Wide Web and display weather forecasts and other data on the display.
Home weather station for microclimate control
A hygrometer will become an indispensable assistant in maintaining optimal climatic conditions in the house. Its readings help to adjust the operation of the humidifier or dehumidifier and bring the level of water vapor in the air to normal.
