500 Air Washers are devices that clean and humidify the air in a room or building. They use a combination of water and air to remove impurities such as dust, pollen, and odors from the air. Air washers typically consist of a water tank, a filter, and a fan. The water in the tank is circulated through the filter, which traps pollutants, while the fan blows air through the wet filter, causing the water to evaporate and humidify the air. Some 500 Air Washers may also include additional features such as ionizers or UV lights to purify the air further.