This 58 cm (22.8'') Dyson cool mist humidifier with Cleanse ultraviolet technology removes 99.9% of the bacteria before mist is projected into the room. Its intelligent climate control device measures both temperature and humidity in the air to create a pleasant environment. Patented Air Multiplier (TM) technology generates long-range mist projection to distribute humidified air evenly. This formula is as effective to standardize air distribution in winter as to direct a high-speed airflow in summer to cool you off. This humidifier operates quietly and is certified against asthma and allergies. Backed by a 2-year limited warranty.