Explained: How do different types of air purifiers work and why do you need one for your home – Times of India

A report published by the United States Environmental Protection Agency in 2021 stated that indoor air pollution is about two to five times worse than outdoor pollution. This means that indoor air can contain up to five times more pollutants like mould, pesticides and particulates compared to the air outdoors. The air inside your rooms may also have allergens like dust, pet dander and pollen. It is a practical and healthy choice to get a device that removes these pollutants and allergens. An air purifier is a perfect device for the situation. As we have to spend more time indoors for the Covid-19 pandemic it is better to respire fresher air while you are inside your house. Here we will discuss how air purifiers work and why are they useful?
What is an air purifier?
An air purifier is an indoor device that traps and filters harmful particles and eventually releases fresh and cleaner air. These devices can restrict the spread of harmful particles and allergens to prevent respiratory diseases or allergies. The device can be used in offices, homes, learning centres, and hospitals to purify the air in these spaces.
How do different types of air purifiers work?
There are four different types of air purifiers that are available in the market which includes — HEPA filter, Activated Carbon Filter, Ionizer, UV Light. Here we discuss how each type of air purifier works:
HEPA filter air purifier — An air purifier with HEPA filters suck air into the device and passes it through the filter using the internal fans. As they pass through the filter, airborne contaminants get trapped inside the dense materials and clean air flows out of the other side. A HEPA filter can capture fine pollutants as tiny as 0.3 microns in size, including dust, pollen, mould, and some bacteria. This makes it the most popular filter among all.
Activated Carbon air purifier — An air purifier that uses an activated carbon filter works the same way as a HEPA filter air purifier does. These air purifiers also pull air through the filter to trap pollutants and allergens. The primary difference between these two types of purifiers is the materials used in the filter. Activated carbon is a specially treated material that has high porosity and can absorb pollutants as air passes through it.
Ioniser air purifier — An ionizer air purifier does not use any filters to clean the air around. These air purifiers emit negatively charged ions that combine with the airborne particles to make them denser. The denser particles get too heavy to move freely in the air and fall onto the ground or other surfaces. The drawback of these types of air purifiers is that the contaminants still exist inside the room until you clean them up.
UV light air purifiers — Air purifiers that come with the Ultraviolet (UV) feature use short-wave UV-C light to destroy airborne germs like bacteria and viruses. It uses a method of disinfection called Ultraviolet Germicidal Irradiation (UVGI). In this method, as air is forced through the device it passes the UV lamp that directly tries to disinfect the air.
Importance of air purifiers
Everyone needs clean indoor air and those who are suffering from allergies and respiratory problems such as asthma have enough reasons to buy one. Improved air quality inside frequently used spaces like — offices, homes, schools and even the car can help to reduce allergy and asthma triggers.
Moreover, modern buildings are designed to be more energy-efficient and they are usually sealed to comply with the requirements. In such cases, the airflow circulation is compromised and pollutants can be trapped inside the house. Air purifiers can also work as artificial ventilation for modern homes.
Some buildings are also exposed to various pollutants starting from vehicle exhaust, construction contaminants, fresh paints among others. Air purifiers can filter all these harmful particles from your indoor air if you are residing in such buildings.