I started purchasing ionizer air purifiers over 30 years ago. Back then my allergies and asthma were so severe I'd try anything. Did the ionizer work? Nope. In fact it irritated my lungs (in a moment you'll know why). Years later the Ionic Breeze purifier made the name "ionizer" popular. However this Sharper Image model was removed from the airwaves for irritating peoples lungs like mine. But not all ionizers cause this problem.
What's the difference between negative ions, ionizers, and ozone? There is a lot of confusion amongst consumers, but what started the confusion was the following problem:
Some "ionizers" (the washable "plate" kind) often create dangerous levels of ozone.
Obviously before you buy one let's get clear about the dangers of ionizers, and the misunderstandings between ionizers, ozone machines, negative ion generators, and what each can do. Ozone and Ions are different.
Several ozone generators are available for sale today with popular names such as Alpine, Ecoquest, Vollara (all the same company) as well as several no-name brands from China. The ozone molecules, by the way, go out into a room and kill odor, they don't work inside the machine itself.
Ozone is a good tool for "treating a room" especially in cases of mold. But too much ozone can irritate lung tissues and airways.
Ionizer Air Purifiers are units that use electrically-charged steel plates (+ and -) to attract pollution and odor molecules. It works because many toxins have charges (+ or -) making the plates operate like magnets. Ionizers include the Oreck with its truman cells (plates), the infamous Ionic Breeze, and just about any air purifier called ionic (although the term ionic is tossed around a lot). These plates are usually washable.
Unfortuantely the flat "ionic plates" have a tendency to create ozone as a byproduct of the positive electrical charge. So even though these manufacturers weren't trying to create ozone it happens. For that matter many appliances like refrigerators and TV's can produce some ozone.
1 - Easy Maintenance - Washable
2 - Good for smoke &odor
1 - Barely works on Dust, pollen (no HEPA)
2 - Expensive (poor value)
3 - Often creates threatening Ozone (check the reviews here to find out)
4 - Won't help remove viruses, or germs (no UV)