Difference between Humidity and Relative Humidity : Pharmaguideline

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Difference between Humidity and Relative Humidity

Meaning of humidity and difference between humidity vs relative humidity, relative humidity measurement methods and their units.
It has been a topic of confusion to differentiate between humidity and relative humidity. Relative humidity is an important factor that affects the quality of pharmaceutical products. It is important to control the humidity in the areas like granulation and compression.

Humidity and relative humidity both measures the amount of water present in the air but both of these have a difference in the method of measurement.

Difference between Humidity and Relative Humidity
Humidity in air depends upon the atmosphere of the area and the season of the year. In the dry areas as desert, humidity remains very low while in the area near ocean and rainforests it remains very high. It also remains higher in the rainy season than the summer. Air can hold a limited amount of moisture or water vapor. When moisture increases above its limit, it turns into the droplets those are known as fog.

Humidity is the amount of moisture or water present in the air in the form of water vapors. It is measured in grams of water in a letter of air (mass/volume). It is also known as absolute humidity.

Relative humidity is the percentage of the moisture against the highest possible level of moisture in the air at a specific temperature. Relative humidity is measured higher at a lower temperature because cold air holds more water vapors than the warm air. Relative humidity is measured by the hygrometer and also known as %RH.

Example: If air of any area has half of the water vapors that it can carry then its relative humidity would be 50%. 100% is the highest and 0% is the lowest value of relative humidity that can be found in any area.

Ankur Choudhary is India's first professional pharmaceutical blogger, author and founder of pharmaguideline.com, a widely-read pharmaceutical blog since 2008. Sign-up for the free email updates for your daily dose of pharmaceutical tips.
.moc.enilediugamrahp@ofni :liamENeed Help: Ask Question

3 comments: Post Yours! Read Comment Policy ▼

  1. change in artwork (text) is change control ?
    who will raise change control in case one carton with x text and secon carton with y text of same item. change in text of carton is change of item code?

  2. Why there is a requirement of monitoring humidity microlab?

  3. Simple and easy to understand. Thanks


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