OVERVIEW:
I first bought an ionizer air purifier back in 1978 to help with allergies and asthma. Did it work? No. It irritated my lungs and in a moment you'll know why. That was long before the Sharper Image Ionic Breeze air purifier made the term Ionic Breeze and "ionizer" synonymous with air purifiers. ionic Breeze was taken off of the market for this very problem. Before you run out and buy one I'd like to clear up many of the misunderstandings between ionizers, ozone, negative ions, and what each can do.
While they are inexpensive to produce and to maintain (no replacement filters) they however have a downside: since most dust and pollen does not have a strong electrical charge an air purifier with ionizer plates fails to work well for allergies. Some of them can also harm your lungs by producing Ozone. More on that in a moment.
Here's a small negative ionizer
if you have a smoke, odor, or mold problem you might want to look for an inexpensive ozone air purifier like this one.
2 - They work well for smoke and odor
3 - Inexpensive to Maintain
Con's 1 - Overpriced
2 - Works poorly, if at all, on dust and pollen
3 - May create dangerous Ozone
4- Will not help with viruses, mold, or germs
2. Particle Removal (Allergens, Dust) 3
3. Immune System Threats (Germs, Virus, etc.) 1
4. Gas Removal (Odor, Chemicals, Smoke) 8
5. Longevity/Quality 6
6. Noise Levels 4
7. Ease of Use 10
8. Warranty 3
9. Customer Service/Reputation (reviews) N/A
10. Price Value 4
My Rating Score: 40 = Fair
Are you a smoker? An air purifier with ionizer plates may be a good option if you are a smoker. Here's why - it clears smoke effectively and you'll save money because you won't have the expense of changing HEPA filters (HEPA does not work to remove the smoke fumes, only the tar and nicotine). If you want to get rid of dust and pollen along with smoke then I'd suggest you get an air purifier with electrostatic and HEPA. The electrostatic will help with smoke and extend the life of the HEPA.
The Video Below is one such model that includes electrostatic, HEPA, Carbon, UV (for germs and viruses), Tio2 and negative ions as well.
Air Purifier With Ionizer Comparison Chart