Buyer’s Guide Everything you need to know before purchasing your air purifier. 1. How UV Light Filters Purify the Air 2. What is Panasonic Nanoe Technology 3. How Ozone Generators Purify the Air 4. How Negative Ion Generators Purify the Air 5. What is Activated Carbon? 6. What are PM2.5 Particles 7. What is a HEPA Filter?