Air purifiers are categorized according to the functions that they perform. You must be aware of which type to buy so that it is able to serve you the best. Different types serve a variety of purposes.
Ionic air purifier
This type of air serves the purpose of reducing airborne allergens that result in breathing problems. It contains an ionizer which is an instrument that charges all the airborne particles. Little specks of dust, allergens get attracted to these. These particles settle down on the surface of the room and so one cannot breathe them in. Many ionic air purifiers have charged metal plates inside which attract particles by themselves so that the dust does not settle on the various surfaces of the home. This variety does not create any irritating sound and they function with energy. The greatest advantage lies with the fact that it does not release any chemicals into the air and they soak in both the dust and the gas molecules making your home free of odor.
The only disadvantage is that all the dust that the purifier attracts settles around it. So it should be placed in such a manner that the surrounding area can be cleaned often. You should also pay attention to the layers in the purifier. You should be aware whether the various layers are serving your purpose or not.
HEPA air purifier
The HEPA air purifiers are able to cleanse the air if the minutest of particles like mold spores, smoke and pollen. They are usually multi layered and therefore it is capable to attract particles of 0.3-micron size. The only thing that you need to keep in mind while buying this type pf air purifier is that you have to ensure that it uses multi layered devices for cleaning and not merely one. HEPA cannot clean bacteria from the air but if an UV system is added bacteria will also be effectively cleaned.
This type of air purifier has only one disadvantage. The filter needs to be changed regularly. It will fail to be effective if it is not replaced.
Ozone air purifier
This type of air purifier poses considerable health hazards and should be avoided at all costs. It is not at all effective to clear the air of pollutants. It can only make your home free of any pungent smell. Ozone has a particular smell of its own with which it replaces the odor. For some the smell of ozone can be as nauseating as the smell they were trying to get rid of. Moreover it is also difficult to control exposure to ozone. It is concentrated near the purifier, which is harmful, but at a distance it is perfect. Therefore it is preferable that you use the traditional methods of air purification rather than the ozone one.
Ultraviolet air purifier
This type of air purifier by itself is not very competent to clean air. It is usually used in combination with some others because though it kills germs it does not remove dust or any other particle. An UV lamp is placed inside the air purifier and it radiates the air that comes through it. This lamp can be put to two uses. It can kill germ directly as well as generate ozone to kill them. If you are really very apprehensive about air borne diseases you can opt for this type of purifier.