Devices that remove impurities such as dust, dirt and pollen grains are known as air purifiers. Pollutants can come indoors from dozens of sources. These devices are helpful to people who suffer from allergy and asthma due to these pollutants. They can also help in eliminating second hand tobacco smoke. On the commercial front, they can be used before Air Handling Unit (AHU) in industrial, medical (Hospitals) and commercial industries. They can also be used in industries to remove impurities such as CO2 from air before processing.

Test have proven that air indoor can be more polluted than the air outside. This may be because of the fact that homes or offices today are virtually sealed to make use of air conditioner or heater more efficiently. This stops fresh air to circulate inside. While some pollutants like pollen come from outdoors, some pollutants are created indoors itself. Carbon monoxide, for example, is usually the result of heat combustion produced by furnaces, cigarettes or auto exhaust that enters a building. Cooking vapour is another such example of pollutant created indoors. Another reason people use these machines is to remove room odour.

So why do you need an air purifier? If you or anyone else is smoking indoors and you do not want your kids or family members who are allergic to dust or smoke to be affected, you will be amazed by how these machines help your cause. Apart from acting as hero to those who have allergies from smoke and dust, these machines also benefit families who own pets. Many quality air purifiers can trap pet hair as well as the stink from their droppings, both are great health hazards. People who own business related to pets and healthcare, for example vets, pet shops or even hospitals, should use one. Clean and fresh air also makes you feel energetic.

The growth of Air purifier India can be attributed to the fact that it has kept these factors in mind while encouraging its use in India. With the rise of pollution levels in India and increase in number of cases of asthma, sales of air purifiers have reached a new height. As rightly so, taking care of loved one is everyone's priority.

The filter is the most important part of good air purifier. The filters clean the air when it passes through it and can also be called as cleaners. It is fitted in the housing so that all the air flowing is filtered. The filters are mostly made up of cotton, synthetic fiber or foam, density of the filters material can vary in size.

Here is a look at  some of the variants in use today?

HEPA (High Efficiency Particulate Air): The filter can consist of any material as long as it meets this standard -- penetration of less than 0.03% of particles 0.3 micrometres in size or larger. The filter must also allow a specific amount of air to flow through, which varies by the size of the filter. In addition to their familiar household uses, cleaning air of allergens and dust particles, advanced HEPA filters are used by the nuclear power industry.

IONIZING PURIFERS: These air purifiers use a method called corona discharge to create charged molecules called ions. Ionizers "charge" particles in the air (ions), which causes them to "bond" with other particles and cling to surfaces in the room, rather than floating in the air. Another reason many units are now incorporating this technology is that these charged particles also cling to each other, creating larger particles which are more easily trapped when passing through filters.

Activated Carbon: They have small absorbent pores that chemically react to pollutants as they pass through the filter. This causes the pollutants to bond with the carbon and become trapped. These purifiers are effective at clearing smoke, odours, chemicals and even gases from the air.

Ultraviolet radiation: UV light is used to destroy germs, bacteria, and viruses. This system helps to not only to clean the air but also clean the germs of fungus in the filter