Ozone air purifiers use electricity to produce ozone and then release into into the air to "seek and destroy" pollutants.  Sounds great, but there are some important drawbacks to consider. 

First, ozone in high doses causes irritation to the eyes, nose and throat.  At very high doses, it can be poisonous to humans.  Now, most ozone air purifiers are not capable of producing those levels of ozone, but it is something to keep in mind.

Second, ozone air purifiers tend to cause an unpleasant "sweet" odor or smell in the room being cleaned.  Most people find this smell objectionable.

Lastly, ozone air purifiers have no affect on solid particles like dust.  Ozone is simply not effective at removing these types of particles.

Of course, along with these negatives comes some strengths as well.  Ozone air purifiers are highly effective against odors.  Ozone also is capable of destroying chemicals and bacteria.  Also, ozone generators do not need to draw air into the machine to be effective, thus it is capable of oxidizing a large area.

Where to Use Ozone Air Purifiers

After taking into all of the above, it is obvious that ozone air purifiers are particularly well-suited for salons, bars, and other areas with high levels of pollution and strong odor.

Ozone air purifiers can also be used in homes as long as the air cleaner utilizes more than ozone technology (i.e. in combination with a HEPA filter).  You would also want to make sure that the ozone generator could be turned off or reduced so that ozone levels could be kept at a minimum