relative humidity

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Related to Relative air humidity: absolute humidity, Specific humidity


the degree of moisture in the air.
absolute humidity the actual amount of vapor in the atmosphere, expressed in milligrams per liter.
relative humidity the percentage of moisture in the air as compared to the amount necessary to cause saturation, which is taken as 100.
humidity therapy the therapeutic use of water to prevent or correct a moisture deficit in the respiratory tract. Under normal conditions the respiratory tract is kept moist by humidifying mechanisms that allow for evaporation of water from the respiratory mucosa. If these mechanisms fail to work, are bypassed (such as with an endotracheal tube), or are inadequate to overcome the drying and irritating effects of therapeutic gases and mucosal crusting, some form of humidification must be provided.

The principal reasons for employing humidity therapy are: (1) to prevent drying and irritation of the respiratory mucosa, (2) to facilitate ventilation and diffusion of oxygen and other therapeutic gases being administered, and (3) to aid in the removal of thick and viscous secretions that obstruct the air passages. Another important use of water aerosol therapy is to aid in obtaining an induced sputum specimen.

Humidity therapy may be delivered in a variety of ways. Humidifiers and vaporizers increase the water content of an environment and are limited to the treatment of upper respiratory disorders because they produce particles that are too large to penetrate deeply into the lungs. Nebulizers generate clouds or mists of particles that are extremely small and thus capable of penetrating more deeply into the bronchioles and small structures of the lower respiratory tract. Examples of these include jet instruments and ultrasonic nebulizers.

rel·a·tive hu·mid·i·ty

the actual amount of water vapor present in the air or in a gas, divided by the amount necessary for saturation at the same temperature and pressure; expressed as a percentage.

relative humidity (r/h)

the amount of moisture in the air compared with the maximum the air could contain at the same temperature.

rel·a·tive hu·mid·i·ty

(rel'ă-tiv hyū-mid'i-tē)
The actual amount of water vapor present in the air or in a gas, divided by the amount necessary for saturation at the same temperature and pressure; expressed as a percentage.

rel·a·tive hu·mid·i·ty

(rel'ă-tiv hyū-mid'i-tē)
Actual amount of water vapor present in air or gas, divided by amount necessary for saturation at same temperature and pressure; expressed as a percentage.
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The equilibrium moisture content of Dedo-de-Moca hot chili pepper varies as a function of relative air humidity for a given temperature.
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1 Results of heart rate, respiration rate and body temperature measurements as a function of relative air humidity, air temperature and atmospheric pressure in the rest period
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In order to verify the influence of the climate changes on water consumption and crop development, alterations predicted for the year 2100 in temperature and relative air humidity were simulated.
They are designed to work in the coal mines firedamp in mine workings methane emanations and relative air humidity of max.
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