Excellent choice for basements, mold infestations, clinics and homes. HEPA Filter - as long as 5 years in normal use. Pre-filters - can be vacuumed from the exterior of the unit and should be changed every 12 months. Carbon Filter - typically last up to 2 years depending on use. UV lamp is effective for 10000 hours.. Pressure seal on the filter chamber lets all unfiltered air pass through without leakage. Filter chamber sealed with felt gaskets. All metal housing ensures no plastic vapors are emitted. Virtually silent. Variable speed motor. Unimpeded airflow. Certified by the Environmental Technology Laboratory. 20 watt UV germicidal lamp. True 40 square foot 2 in. deep folded HEPA filter traps 99.97% of particles as small as 0.3 microns. 18 lb carbon filter absorbs airborne chemicals, noxious gases and odors. Approximate treatment area is 2000 sq. ft.. Particle removal: 40 sq. ft. true HEPA, 2 in. deep, 10 pleats per in., pleats warm rolled with separators. Odor and chemical suppression: 18 lbs. carbon filter 2 in. deep carbon bed. Free Air Flow: 560 cubic feet per minute free flow, delivers 440 cfm with filters. Pre-filter: 570 sq. in. and 1 in. deep. Housing: Powder cost steel. Voltage Options: 115 or 220 Volts. Watts: 120 on high 40 on low. Noise: 28.1 db on low 62.3 db on high. Normal room sound is 25.1 db. 15 in. L x 15 in. W x 23 in. H (45 lbs.).