The Defender® works 24 hours a day to reduce indoor air pollution from your home at a filtration level that is three times better than HEPA. Energy efficient and quiet, the Defender® actually filters many of the tiny, harmful particles that HEPA cleaners leave behind. Beware of silent air cleaners – many produce ozone which may be problematic to your health. • Better-than-HEPA Filtration* • Proven Effective Through Laboratory Testing • Recognized by the FDA as a Class II Medical Device • Energy Efficient • Quiet, 24-Hour Operation • 3-Speed Programmable Operation • Change Filter Indicator Light • Secure Seal Technology • Pure Top Release • HMI is certified to ISO Standards (ISO 9001 and ISO 13485) * HEPA is the industry's filtration standard. Products with HEPA filtration reduce 99.97% of pollutants down to 0.3 micron. The filters used in the FilterQueen® Majestic® and Defender® reduce 99.98% of pollutants down to 0.1 micron.