relative humidity

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Related to relative humidity: absolute humidity, dew point


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.
References in periodicals archive ?
Reducing relative humidity is a practical way to control dust mites and their allergens in homes in temperate climates.
When the temperature and relative humidity were held steady, the percentage of arenes increased as the ratio of air exchange rate-to-loading factor increased, but the percentage of alkenes and of aldehydes and ketones decreased at the same rate as this ratio increased (Fig.
in southern and northern regions, average percentage of relative humidity in summer and fall months is in the 80's in the morning and in the 60's in the afternoon (COAPS 2015).
Negative correlation can also be seen between aphid population build up and relative humidity (Table III).
o In controlled chamber with 95% relative humidity the compressive strength of SLM remained higher than KLM samples which was 2.
Effect of relative humidity and cryopreservation for ash percentage at probability level of 5% were not significantly different, but the treated samples in humid condition had the highest percentage after 6 months with 6.
Relative humidity increased towards the end of the season as temperature decreased.
The incidence of berry cracking, after the transference of fruits from the cold chamber (0 days at 20[degrees]C), was directly related to relative humidity during storage and was only noticed when it was equal to or above 95%, which corroborates the findings by SCHWARZ (1994) (Figure 1B).
As a result, it was determined minimum error rates of the measured and simulated air temperature and relative humidity in greenhouses is 4.
More helpful is the number you usually get in a weather report: relative humidity (RH).
There is a striking relationship between how well climate models simulate relative humidity in key areas and how much warming they show in response to increasing carbon dioxide," says NCAR scientist and study co-author John Fasullo.
They found that an hour after being released in a room at a relative humidity of 23 percent or less, 70-77 percent of viral particles retained their infectious capacity, but when humidity was increased to about 43 percent, only 14 percent of the virus particles were capable of infecting cells.