The Honeywell Cool Moisture Humidifier helps temporarily relieve dry air discomforts for better home comfort. UV technology kills up to 99.9% of certain bacteria mold fungus and virus in the water after 2 hours of continuous use. This provides the assurance that the moisture emitted from the unit is virtually free of germs. Patented Germ Killing Technology kills up to 99.9% of certain bacteria mold fungus and virus in the water; Quiet Operation - Up to 25% Quieter than other evaporative humidifiers; Durable break resistent water tank; Dishwasher safe water tank and tray; Self Regulating Evaporative System. Adjusts output to the amount of moisture the air can hold at a particular temperature; Protec Antimicrobially Treated Filter; Perfect for Medium Size Rooms such as Bedrooms and Living Rooms; Runs up to 24 hrs per filling.