Supply moisture meter and sound level meter,etc.

Dew Point Meter

Dew point meters are devices which are used to measure dew point over a wide range of temperatures

The dew point or dewpoint of a given parcel of air is the temperature to which the parcel must be cooled, at constant barometric pressure, for the water vapor component to condense into water, called dew

The dew point is an important statistic for general aviation pilots, as it is used to calculate the likelihood of carburetor icing and fog, and to estimate the height of the cloud base.

The dew point is the temperature of an airmass if you could cool it down to the point of condensation. If there's a lot of moisture in the air, you won't have to lower the temperature very much to reach the dewpoint.
Dew point, or otherwise better known as dew point temperature, is the temperature at which the liquid and gaseous phases of a material present in a gas, such as water in air, are in equilibrium at a given gas pressure. In the case of water, the temperature at which both evaporation and condensation of water take place are the same.

The dew point temperature is the temperature to which the air must be cooled to reach saturation (assuming air pressure remains the same). The dew point is a direct measure of the amount of moisture present in the air, and directly affects how you feel and measures the amount of humidity in the air.

Dewpoint is the temperature air will reach saturation when air cools and maintains a constant pressure and constant moisture content.