I do not have a preference between a warm or a cool mist humidifier since both accomplish the same thing--getting moisture into the air. However, the warm mist type can generate warm steam that may cause any wallpaper in the baby's room to become unglued while the cool mist variety may make the air in the room much more cooler than usual. In my opinion, there is no real need to get too fancy by buying an ultrasonic type that makes smaller droplets of moisture. It is much more important to keep whichever humidifier you use clean, so that you are not spreading germs.
Cold Versus Warm Humidifiers
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