The Blueair model 501 air purifier uses the two-stage HEPASilent™ filtration system, which provides a high level of filtration at low pressure for extra air purification and less noise. The unit traps 99.97% of all airborne allergens and lung-damaging pollutants at 0.1 µm. The system traps pollutants such as pollen, dust, bacteria, pet dander, automotive exhaust, and mold spores. The Blueair model 501 air purifier is capable of operating 24 hours a day, 7 days a week, and is designed to purify a 620-sq-ft room.

Blueair Inc
(888) 258-3247; www.blueair.com