HOW DOES AIR PURIFIER WORK?

Air Purifiers are very simple machines, primary comprising of three parts
1. A filter
2. A fan and
3. A box

The box is normally made of polymer (plastic) to hold a filter and a fan. When the Air Purifier switched on, the fan starts to pull air from outside of the box. But air being drawn in by the fan has to pass though the filter placed in between.

This is true for all types of large Air Purifiers, irrespective of their shapes. However, with that said, not all Air Purifiers performs equal. Because of the size of the grill to allow the air in, permeability of the filter being used and the speed and size of fan.

So technically, you can also make your own fully functioning Air Purifier, just by placing any filter (such as HEPA) before or after a fan. The air passing through this filter would be purified air.

The above image shows air entering in the air purifier before the green colour filter.

The air is further drawn in through the front side green air filter by the running fan. The air passing though the filter is shown as green to depict clean air.

Looks familiar? This is also how the air filter works. Preventing the particles larger than the size of filter's hole from going through it.

The clean air moves from the back of the filter towards the front of fan. The filter has been removed to show the back side of filter where the fan is placed. The green filtered air has been shown entering from one side of fan and getting out from the top outlet grill of the box.