# How to determine the humidity of the air?

A person’s well-being is influenced by many different factors - clean air, the presence of sunlight, the quality of food, water and other important factors, thanks to which you can maintain youth and health throughout life. These factors include humidity. It has long been known that very dry air, like too humid, has a bad effect on people's well-being. Therefore, it is important to know how to determine the humidity of the air, and then adjust it to the desired parameter.

Let us further consider how to measure the humidity of the air and determine the relative and absolute humidity.

## How to find the humidity

Today, moisture can be measured in several simple ways.

• With the help of special devices like hygrometer and psychrometer. There are a lot of models of measuring instruments on the market, but when buying, you should always pay attention to accuracy. If the deviation from the values ​​can be from 1%, then you should not buy such a device because of the inaccuracy of measuring the humidity of the air in the room.This is especially true for various inspections and compliance with the rules of comfortable location of employees in the premises.
• You can measure the humidity and improvised means, using a glass of water and a refrigerator. To do this, put a glass of water in the refrigerator until the water temperature is 3-5 degrees Celsius. After that, put the glass in the room and watch him. If the glass is fogged up and then dried for 5-10 minutes, then the air is very dry. If during the same time drops began to form in the glass and run down the walls, the air is very humid. In other cases, the humidity of the air is quite suitable for a healthy lifestyle.
• Measurement with a thermometer. This method perfectly copies measurements using a psychrometer. Record the temperature of the room, and then wrap the thermometer with wet gauze and wait ten minutes. Then we compare the temperatures before and after. We subtract the second variant from the first one and look at the special table of values ​​in this way. You will find out the humidity in the room.

Often, the concepts of absolute and relative humidity are used in weather forecasts and in moisture measurements.

## How to determine the absolute humidity

To denote the moisture content in the air, use the value of absolute humidity, which is the ratio of the mass of water vapor to a unit volume of air:

f = m / v.

In the world of absolute humidity varies greatly by region. For example, in winter over continents the absolute humidity is approximately equal to one, and in the equatorial zone it can reach up to thirty. Usually, a value equal to one is used in the default formulas, unless otherwise stated in the conditions.

The concept of “maximum humidity” is also distinguished, which shows the maximum value of air humidity at a certain temperature at thermodynamic equilibrium.

## How to determine the relative humidity

Relative humidity is measured in percent and is the ratio of absolute humidity to maximum multiplied by 100%. This parameter is often used in meteorological reports and weather forecasts.

Also, relative humidity is found from the ratio of vapor pressure to saturated vapor pressure, or due to knowledge of temperature and dew point temperature under specific conditions:

RH = P / P (saturated steam) * 100%.