A quick guide on RH concept, importance and calculation

Relative humidity

Humidity, a word to describe either sipping margaritas from the sea facing hotel room or the icky moments where you get poofy hair, depending upon the experience one faces. While we always think humidity is a never-ending torture, no one thinks what exact role humidity plays in our lives. Countries with harsh conditions, popularly use humidifiers which now has become a staple in the beauty industry as well.

But without even understanding the concept of humidity, it is wrong to use the term and bounce it off without giving a thought. Scroll down more to find out what humidity is, relative humidity in particular, terminology used in relation with it, what role it plays and how one can calculate relative humidity.

What is humidity?

Humidity is defined as the amount of water vapor that is present in the air. The value of water vapor present decides the wet feeling one gets, meaning high humidity. Similarly, low humidity makes you reach for your thick lotions and body oils while making you feel totally dehydrated. When it comes to expressing humidity in terms of weather conditions, relative humidity is something used to define accurately.

What is Relative Humidity?

Relative humidity is a standard way used to measure the humidity, in the given temperature. It is important to note that, to understand relative humidity, one should also know what absolute humidity is. Absolute humidity is the ratio of masses of water vapor with respect to dry air where values of volume and temperature are fixed. To define relative humidity in scientific terms, one can say relative humidity is the ratio of the present value of absolute humidity to the highest possible value it can reach at a fixed temperature. The unit used here to express is grams of moisture per cubic meter of air (g/m3).

While describing relative humidity, it is common misconception to say it is the amount of water holding capacity, but in reality, water vapor does not possess any binding or attraction capability to agree with the term. So, to accurately describe relative humidity, it is the certain quantity of water vapor that can exist as a component of air.

Another term commonly used regarding relative humidity is dew point. Dew point is defined as when relative humidity attains 100 per cent or saturation point. In an ideal scenario, we humans generally feel comfortable when dew point is around 55.

Why is relative humidity important?

Relative humidity has been playing an important role in many scenarios and systems. The relative humidity is majorly used to determine the moisture levels in a particular system or circuit to improve and maintain efficiency. Humidifiers, that most youtubers and beauty influencers swear the secret to their plump dewy skin, have been now used more, thanks to the weather changes happening all over the world. Similarly, dehumidifiers have been a staple in really humid places as well. Air conditioners, HVAC filters and thermostats which use automations systems also require the concept of relative humidity to make sure of a comfortable atmosphere.

Clean rooms , which are widely used in manufacturing various gadgets and testing, medical practices and collecting samples, all require a standard way to measure moisture present in the air. Virology studies and procedures also depend on relative humidity to understand many factors like origin, breeding etc.

Storage facilities for food or pharmaceuticals also rely on relative humidity for storage and decide the equipment to monitor so as to make sure the product quality is not compromised.

Building materials and floorings, practices to prevent moulds and fungus also use relative humidity as it prevents material loss on a large scale. For constructions involving concrete and floorings, relative humidity is an important deciding factor to avert unfortunate events.

How to calculate relative humidity?

Relative humidity is calculated by a simple formula, stated below,

Relative humidity = actual vapor density * 100%
saturation vapor density

where actual vapor density is the value of water vapor present in the air in a particular area at the given temperature,

saturation vapor density is the highest value of water vapor can be achieved in the air in a particular area at the given temperature.

To wrap things up, relative humidity finds itself in a wide range of applications, be it for human comfort or to perform complex scientific studies. To understand relative humidity in a precise accurate manner could help in many ways by eliminating common misconceptions regarding it’s definition or applications or importance of the same. And also, relative humidity provides a standard approach making sure no confusion and material loss happens thus saving costs and efforts.

Articles you may also like