Blueair 402

For rooms up to 365 square feet, this air purification system features two-stage HEPASilent technology that captures 99.97-percent of 0.1 micron particles, including allergy-provoking pollen grains, dust mites, mold spores, and pet dander particles. Particles that a HEPA filter alone might miss are captured with an electrostatic charge. HEPASilent technology moves particles through an enclosed ion chamber, which attaches a charge to the particle itself. Charged particles cling more easily to the filter media, resulting in higher filter efficiency overall. Because most electrostatic air cleaners charge the filter media itself, the charge dissipates over time and renders the filter less efficient. By constantly charging incoming particles, instead of the filter, HEPASilent technology keeps on working effectively. The air purifier's HEPASilent filter technology is geared towards a more environmentally friendly design as well. Its nontoxic polypropylene filter contains millions of ultra-thin fibers that trap tiny particles as they pass through the pleats. One of the least harmful plastics for human health and the environment, polypropylene works without outgassing or shedding irritating microscopic fibers into the air. Because polypropylene is waterproof, the filter resists contamination from bacteria, viruses, and mold naturally, without chemical additives. And as used filters are discarded and decompose, the filter media converts into harmless carbon dioxide and water. Not only does the unit clean air with environmentally friendly filters, it?s HEPASilent filter technology also allows for extremely quiet operation. On the lowest setting, the unit emits no more sound than a desktop computer.