Did you know that the worst air pollution is indoor air pollution? We've become huge air purifier fans (no pun intended) and these pictures are living proof that our air, at least, is dirty and is now cleaner. And we'd far rather have all this thick fuzzy grey mat of particles on that filter than still circulating in our home.
In our small apartment we have three air purifiers. This one is the bigger one and it lives in the closet, but is able to circulate air throughout the main room. It's a Honeywell Ultra Quiet HEPA unit, and what you are seeing is all the dirt it has collected since September. That's roughly four months. We feel that with these machines, not only is our air noticeably cleaner, our apartment is as well. They take out of the air a lot of the dust particles that would otherwise settle on our surfaces, so, in a sense, we don't have to clean as much.
The reason we're vacuuming the filter is because this unit has one of those long, endless life filters that can be cleaned in this way. You vacuum off the outside of the filter every few months or so and it should last you a couple of years. That's the theory at least. We'll review it in our Test Lab when we've had a bit more experience.