We purchased the Pure MistAire Silver Ultrasonic Cool Mist Humidifier at our local pharmacy as I was suffering with a bad cold and needed to get something quickly. This little humidifier is amazing. It raised the humidity in our bedroom by 7-10% (as recorded on hygrometer) depending on how much our furnace was running. Powerful little humidifier that is almost silent when operating on high output. Our Montana winter air is so dry and the Pure MistAire mist is so fine that it evaporates before it can land on any horizontal surface. Definitely makes a difference when trying to sleep while congested.