A device for measuring air humidity and features of its application

From this article you can find out what a device should be for measuring air humidity. The text discusses the main types of devices designed to control climate by measuring water vapor in the air. The existing types of devices, their technical and operational features, rules of use are described here.

Air humidity measuring device and its specifics

Humidity affects the state of furnishings, household appliances and human well-being. The presence of water vapor in a certain amount in the air depends on the following factors: anthropogenic impact, climatic features of the region, the state of communications and buildings in general, as well as the operating conditions of the room.

The humidity standard for a healthy person is considered to be 40-60%. To create optimal conditions, special devices are used. These can be dehumidifiers or humidifiers, depending on your needs. Air humidity meters are used to coordinate the operation of these devices.

Note! There are air conditioning systems with an automated moisture control function. This type of equipment independently measures air indicators and adjusts them to the norm.

How is air humidity measured in residential premises

You can measure the amount of water vapor at home using available tools, for example, a spruce cone, whose scales open if the room is dry, or monitor the condition of the condensate by first cooling the container with water.

The container method is based on how the condensate behaves on cooled surfaces and at what rate it evaporates.The environment in a closed space under the condition of balanced condensation and evaporation processes is in a state of saturated steam. If the amount of moisture in saturated steam is close to the concentration of water vapor in the air of the room, then the evaporation process will be difficult. This will indicate the presence of excessive moisture in the room.

How to measure the humidity in an apartment using a glass:

1. Fill a glass container with water. For these purposes, not only a glass is suitable, but also a bottle, a jar.
2. Place the container in the refrigerator for a couple of hours.
3. Then take out the glass and measure the temperature of the water. This indicator should not exceed 50 ° C.
4. The test vessel should be placed in a room away from heating appliances.

Note! Time must be taken to observe the behavior of the condensate. This will take 5 to 10 minutes.

If the condensate accumulated on the walls dries out within the specified time, then the room is dry. Wet glass indicates that the room has optimal conditions with a sufficient level of humidity. If the drops of condensate are large and run down the walls of the vessel in streams, this indicates an increased amount of water vapor in the room.

What devices are used to measure air humidity

More accurate data can be obtained using special instruments. For these purposes, several types of devices are provided. The most primitive devices that measure indoor air humidity are called hygrometers.

This category of devices includes the following types of devices:

• ceramic;
• electronic;
• weight;
• electrolytic;

• condensing;
• hair;
• film.

Each type of the listed devices functions due to a certain principle of operation, for example, the structural feature of the hair device is the presence of U-shaped tubes. The condensing hygrometer is considered the most accurate. It takes measurements with minimal error.

There is another category of devices for measuring air humidity, they are called psychrometers. Types of psychrometers:

• station;
• remote;
• aspiration.

The station version of the device is the most popular of them. Its design includes a pair of thermometers mounted on a tripod. A dry thermometer shows the air temperature in a room, a wet one is wrapped in a cloth, one end of which is lowered into a tank filled with liquid (water).

Note! Do not lower the end of the wet thermometer directly into the reservoir, otherwise it will display the temperature of the water, and not the air masses circulating above it. There must be a distance of at least 30-40 mm between the end of the device and the container.

Classification of instruments for measuring the relative humidity of air (hygrometers)

A person's health status depends on a large number of factors. An important role in this is assigned to the purity and humidity of the air. If there is not enough moisture in the room, the mucous membranes of the respiratory tract will dry out, as a result of which a person may develop diseases associated with the vital activity of harmful bacteria.

The simplest hygrometers assume the use of a table of relative air humidity, according to the temperature indicated in it, you can get an idea of ​​the state of the microclimate at the moment. More advanced models have a set of microcircuits that independently perform calculations and display the result on the screen in electronic form.

 

In addition to traditional designs, the offer of the modern market allows you to buy moisture meters with additional functionality.Such devices display other data on the screen:

• air temperature in the room;
• current time and date;
• atmospheric pressure level.

Note! Some types of devices are equipped with an indication system. It informs the owner if the room microclimate is out of the normal range. This function allows you to timely notice the problem and fix it.

Features of hair room air humidity meter

This type of device is used to determine the moisture content in the range of 30-80%. The design of the device consists of several elements:

• metal frame in the form of a frame;
• measuring scale (step of each division corresponds to 1% humidity);
• human hair (fat free);
• adjustable arrow with a screw;
• a pulley designed to be able to throw the free end of the hair with a fixed weight.

A hair hygrometer is a type of measuring device designed to determine air humidity, the principle of which is based on the hygroscopicity of a human hair, in other words, the ability to lengthen or shorten under the influence of moisture. When the humidity in the room decreases or increases, the tension on the hair decreases or, conversely, increases. As a result, the pulley turns and drives the arrow pointing to the scale. Due to this, an accurate indicator of the ambient humidity can be determined.

The hair type hygrometer has a significant advantage over other devices. Its readings cannot be affected by the air temperature, as is the case with electrolytic models. It does not require electricity for its operation, the hygrometer functions due to mechanical processes.

Related article:

Air purifier for an apartment: which device to choose for home use

How to choose a device option to create comfortable climatic conditions. Types of structures, their characteristics, the best models of cleaners.

What device measures air humidity in its absolute value

In order to identify the current level of humidity in the room, you should know two values: the relative humidity and the absolute value. The percentage between them is the desired parameter. Therefore, it will be useful to know the name of the device for measuring air humidity in its absolute value and the principle of its operation. A weighing hygrometer measures the amount of water vapor contained in one unit of air (in 1 m³).

The device includes several U-tubes forming a system. Inside them there is a hygroscopic substance that absorbs moisture from air masses. A certain volume of air passes through the system, which is taken from one point. This design allows you to determine the mass of air inlet and outlet, as well as its volume. The absolute value is determined by mathematical calculations.

Interesting fact! The study of water vapor as one of the components of air began in the 16th century. J. Port became the author of the first scientific work on this topic. It was published in the 17th century. After the flourishing of steam engines in the 19th and 20th centuries. water vapor again interested scientists. After serious research in this area, in 1963 the Fourth International Conference devoted to its physical characteristics was held.

Characteristics of ceramic instruments for determining air humidity

Ceramic devices are a commonly used type of moisture meter; moisture meters of this type are simple and operate mechanically. The device is made of ceramic mass, which can be porous or solid.It contains metal elements. The ceramic mass has an electrical resistance, and the humidity of the room has a direct influence on the level of this resistance.

In order for the mechanical structure of the indoor humidity meter to function properly, certain metal oxides must be included in the ceramic mass. Silicon, clay and kaolin are used as base.

Features of condensing devices for measuring air humidity in an apartment

The condensing hygrometer makes it possible to obtain the most accurate indicators that reflect the climatic comfort of the room. It is for this reason that many consumers will choose to buy this type of indoor air humidity meter.

The design of the device consists of the following elements:

• metal box;
• thermometer;
• rubber bulb;
• heat insulating gasket;
• front wall;
• ring.

The condenser version of the humidity and temperature meter analyzes the amount of condensation that forms on the glass surface. A small beam of light is directed to a special mirror, which is cooled, as a result of which drops of water or ice crystals appear on the surface. An electronic thermometer built into the mirror determines the temperature. The device converts the received data into an indicator that displays the level of relative humidity.

Note! Consumers can select and buy an improved modification of the air humidity meter. Such models are equipped with a display designed to display readings. The advantage of such devices lies in long-term stability. The devices are characterized by a long service life and an extended operating range (device covers from 0 to 100%).

Features of electronic temperature and humidity meters

The capabilities of an electronic device for measuring air humidity in a room allow you to measure changes in the concentration of electrolyte, which covers a material with electrical insulating properties. These materials include plastic and glass. Some device variants have an automatic heating function. They measure the dew point.

In addition, temperature fluctuations are taken into account, since it can affect the operation of the device, albeit insignificantly, therefore the devices are equipped with thermometers that facilitate their operation.

Electronic modifications are precise in measurements that mechanical designs cannot offer. The percentage of errors in their work is extremely low.

Consumers can buy air humidity meters with different specifics of work:

1. Air conductivity measurement - devices determine the value of absolute humidity. To calculate the indicator of relative humidity, you need to measure the temperature.
2. Optoelectronic measurements - the instruments measure the dew point using a cooled mirror. It is frozen, after which there is a process of gradual heating.
3. Resistive measurements - the devices are based on the effect of changing the conductivity of polymers or salts under the influence of moisture levels.
4. Capacitive measurements - during operation, the unit monitors the change in the capacitance of a capacitor (polymer or metal oxide).

How to measure humidity at home using a psychrometer

Psychrometers are designed to determine the indicator of relative humidity. The device functions due to the physical properties of the liquid, in particular, its ability to evaporate.In the process, there is a difference between the temperature readings of the wet and dry bulb thermometer. Part of the energy is lost by the liquid during evaporation, which causes a decrease in temperature. This change is picked up by the thermometer.

The construction of a psychrometer consists of a pair of alcohol or mercury psychrometers. During the evaporation of the liquid, the wet bulb is cooled. The lower the humidity level, the faster the liquid evaporates. In turn, the drier the air, the lower the temperature indicator displayed by wet thermometers. Due to this, there is a difference between the readings.

Note! Regardless of which device measures the humidity of the air, it is not allowed to install it near radiators or air conditioners, otherwise the measurements will be inaccurate. In addition, you need to monitor the condition of the material for moistening. It must be clean and wet.

Some psychrometric hygrometers require specific temperature conditions. For example, the lowest permissible value for winter is -15 ° C, for summer the highest temperature limit is 40 ° C. The measuring range is temperature dependent, the ambient humidity table can be used as a guide.

Measurement range according to the air humidity table:

Air temperature, ºС	Allowable range,%
from 20 to 23	from 54 to 90
from 24 to 26	from 40 to 90
from 27 to 40	from 20 to 90

 

Room humidity level: how to measure the amount of water vapor

The process of measuring humidity with a psychrometer is very simple. In addition to this value, the device also measures a temperature parameter. As a rule, together with alcohol thermometers fixed on a plastic base, the manufacturer places a psychrometric table of relative air humidity, which allows reading the readings.

There is one important condition for the correct operation of the device. The psychrometer is extremely sensitive to drafts, therefore it is recommended to create conditions under which the speed of movement of air masses in the room should not be more than 1 m / s, otherwise the difference in readings taken from thermometers will be much greater than in reality, which will lead to obtaining inaccurate result.

The psychrometric table of air humidity is used to decipher the psychrometer readings. The first column contains the temperature readings of the dry bulb thermometer. The first line displays the difference during measurement between the readings of both thermometers. To get the actual level of relative humidity, you need to take the value that is formed at the intersection of the corresponding parameter from the first column and the first row.

The Assman psychrometer is an improved modification of the device, which makes measurements more accurately and is not afraid of drafts, since its thermometers are protected from heat and direct sunlight due to the metal case.

Home weather stations for convenient microclimate control

For consumers who pay increased attention to their own health and strive to bring air indicators closer to the optimal value, manufacturers of climatic equipment offer to buy an electronic hygrometer - a humidity and temperature meter and a barometer in one device. A design with similar functionality is able to fully control 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. Unusual combinations can also be found on sale, for example, a radio nanny 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 forecast and other data on the display.

The hygrometer will become an irreplaceable assistant in maintaining optimal climatic conditions in the house. Its readings help to correct the operation of the humidifier or dehumidifier and bring the level of water vapor in the air to normal.