A humidifier is essentially designed to improve the air quality of any given room by increasing the ambient moisture and thereby decreasing the amount of particles in the air. You can buy these devices to improve the air in just one room or all over your house. There are different types of humidifiers, depending on how you want to use them.

If you only want to increase the moisture in the air of your bedroom then perhaps a single point machine i.e. one that is meant to be used and kept in one place only, is best for you. Furnaces are used when a person wants to increase the moisture all over their house and they are connected to your existing heating and air conditioning unit. Finally, for those who only want to change the air of the room they are in, a portable humidifier is probably the best option.

Though there is a vast selection of humidifiers, the wick humidifier is the most popular. The wick humidifier is made up of three basic elements, the reservoir, the wick and the fan. The reservoir is a tank containing water that is filled before the humidifier is in use, this water is used for the moisture that the machine sends into the air. Not all humidifiers use a reservoir, some have a continuous feed to a water line but are often more expensive.

The evaporation rate of the water used by the wick humidifier varies based on the amount of humidity in a room. A room with low humidity means that the water will evaporate more quickly and where there is greater humidity the water will take longer to evaporate - in this sense the humidifier is self regulating because it adjusts according to differing humidity levels. With this type of machine you must remember to clean and change the wick on a regular basis. Water will remain at the same level in the tank because if the wick is dirty or needs changing the machine cannot continue to humidify the area it is in. The final part of a humidifier is the fan. The fan is usually next to the wick and is designed to blow air across the wick to increase the rate at which the water evaporates through the wick.

Of all the various humidifiers on the market today, the vaporizer is probably the best for patients suffering upper respiratory conditions. The water has to be boiled, which uses more electricity, but the steam can be medicated and there are no harmful minerals in the steam. The impeller uses a rotating disc to fling water at a diffuser, which then sprinkles the droplets of water throughout the room. The ultrasonic has a metal cage that vibrates at a frequency that is ultrasonic (beyond sound) and this creates drops of water, which are then distributed round the room as a cool mist. Ultrasonic humidifiers need regular cleaning in order to prevent any bacteria or other contaminants being distributed with the moisture.