This air filter has been cleaned and is ready to use- it does not appear to have many hours of use
I can refer you to the online manual- The following description is from that online manual:
How the Oreck Air Purifier Works
1. Polluted air enters the Air Purifier through the front grill. As
the air is pulled through, a Pre-Filter helps trap large particles
(hair, lint, etc.).
2. A Positive Charging Wire electrostatically charges smaller
particles (dust, smoke, pollen).
3. The positively charged particles then enter the negatively
charged Electronic Collector Cell, where the aluminum plates
attract and retain the particles. It works like a powerful
magnet and the particles remain until the Electronic Collector
Cell is cleaned.
4. The air then passes through a Charcoal Odor Absorber that
helps remove household odors.
5. Next, the Air Revitalizer (Ionizer) releases negative ions to
freshen the air.
The negative ions created by the Air Revitalizer may also
combine with dust, causing the dust to fall out of the air. This
feature gives you an easy, centralized place to wipe away
dust.
Finally, electronically cleaned air passes back into the room
through the top grill
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