As Americans grow more concerned about the air they breathe the demand for air purifiers constantly rise. The air purifying industry has not missed this rising interest and they are now flooding the market with all sorts of air purifying gadgets. Each comes with special features and new promises. However if we go to the basic technology behind all these various models we will notice that air purifiers are actually of three main varieties

- Ionic air purifier
- HEPA air purifier and
- Ozone air purifier

There is also a fourth variation - the UV air purifier but these mostly come in combination with the HEPA air purifier.

Ionic Air Purifier: This variety of air purifier works on a principle which seems to be inspired from how static electricity actually draws particle towards itself. In an ionic air purifier there are charged sheets inside which actually draws the neutrally charged particulates from the air. Although this works with bigger particulates, it tends to miss out on a whole lot of other pollutants present in air. So such purifiers are very basic and improve the quality of the air partially.

HEPA Air Purifier: these purifiers are much more advanced than the ionic air purifier. In fact HEPA air purifiers actually filter the air inside rooms. A HEPA air purifier draws in the air from the room, filters the particles present in the air and then releases the cleansed air. A HEPA filter is good enough to capture particulates as small as 0.3 microns. Such levels of purification is truly remarkable and even hospitals use HEPA air purifiers.

However, there are a number of particulates, especially organisms including a few bacteria, viruses and germs which are less than 0.3 microns. For such organisms the UV air purifier has been introduced. They either come with HEPA air purifiers or they are stand alone machines. The UV air purifier emits UV light which actually alters the DNA and RNA of the microscopic organisms so that hey are sterilized and cannot continue to multiply inside our body.

Ozone Air Purifier: This is perhaps the most controversial of all air purifier as many think that constant exposure to ozone at close proximity cannot be good for the human body. However, there are believers too. This purifier actually releases ozone in the air. The third oxygen atom of the ozone gets detached and combines with the particulates while the remaining two are released as an oxygen molecule in the air. Oxygen works as a cleaning agent.