Evaporative humidification for spaces up to 645 square feet* Healthy air humidified to an optimal 40-60% Safe for use with tap water Naturally reduces harmful pollutants in the air at a humidity level of 40-60% Digital hygrostat for measuring and controlling the relative humidity Interactive touch display *Total coverage area including adjoining rooms, hallways, and stairways. Based on standard 8-foot ceilings.