To breathe clean air, use clean water in the humidifiers
Household humidifiers are usually used to mitigate and alleviate the aggravating conditions of dry skin, dry lips, dry nose, and dry throat of people living in arid climates or a dry indoor environment. Humidifiers also add moisture to the relatively dry air to lessen the problems caused by winter heating—such as static electricity, detaching and peeling wallpaper and paint, and cracks in furniture. In arid climates, humidifiers can definitely make life more comfortable.
A humidifier is a small household appliance that increases the moisture or humidity of a room or a house by dispensing vapor directly into that room or house. There are five broad categories of commercially available humidifiers in the market: ultrasonic humidifiers, evaporative or wick humidifiers, vaporizers (also commonly called steam humidifiers or warm-mist humidifiers), impeller humidifiers (or cool-mist humidifiers), and forced-air or bypass humidifiers (this is not a portable humidifier but a unit built into the furnace). A brief description of each of these humidifiers is provided as follows:
- Ultrasonic humidifiers - This group of humidifiers employs a metal diaphragm or a thin, flexible disk vibrates at an ultrasonic frequency—much like the microphone or loudspeaker—to create tiny water droplets. This type of humidifier is usually energy-efficient, silent (as it vibrates at a frequency above the human hearing range), and produces a cool mist. The water reservoir must be cleaned frequently so as to avoid bacterial and other microbial propagation into the air. Because the water is not boiled or heated in this system, bacteria and other microorganisms can grow and proliferate rapidly in stagnant water, causing the release of microbe-filled moisture. For people who have weak immune systems, it is best to clean the water reservoir frequently and fill the reservoir with only filtered, purified water.
- Evaporative or wick humidifiers - This type of humidifier has been the most popular in the market. It consists of three basic parts: reservoir, wick, and fan. The reservoir is simply a water-storage container that provides water for vapor or moisture output. It is important to keep this vessel clean and free of bacteria and other microorganisms and physical contaminants so that the humidifier will not propagate microbes along with moisture to the entire room or house. The second component is the wick, which is essentially a filter (made of foam, paper, or cloth) or sheet that soaks up water from the reservoir; evaporation of water from the wick then provides moisture to the room. This type of humidifier is self-regulated, meaning that as the relative humidity of the room or house increases, the evaporation from the wick decreases; as the room becomes drier, evaporation from the wick speeds up. The third component, the fan, is placed adjacent to the wick and blows air onto the wick, facilitating the evaporation of water from the wick.
- Vaporizers, steam humidifiers, or warm-mist humidifiers - With this type of humidifier, water is boiled and released as warm steam into the room or house. Although this is the simplest and least expensive of humidifiers, it can be hazardous around children because the boiling water can cause burns. This category of humidifiers is also the most energy-intensive because it has to boil the water before releasing water as vapor into the room. But an advantage with this type of system is that since it boils the water, there is no bacterial and microbial contamination in the water vapor it releases. But we still recommend users of this system to use only filtered, purified water with the vaporizers because water that contains other types of pollutants (such as volatile chemicals) can cause the release of chemical pollutants along with water vapor into the room.
- Impeller or cool-mist humidifiers - With this type of humidifier, a rotating disc pitches water at a comb-like diffuser; the diffuser breaks the water into tiny droplets that then drift and suspend in the air. Since water is not boiled or heated, the fine water drops appear as a cool mist projecting out of the humidifier. Water tends to get stagnant in the reservoir, so it is best to clean the reservoir frequently and fill it with only filtered, purified water so as to prevent microorganisms from proliferating in the tank and then get projected into the room. If using high-mineral-content tap water or well water, minerals will get projected in the air along with water vapor. People who use this type of system may notice the minerals as dust and the mineral dust may cause respiratory problems in the long term for the sick and elderly. Therefore, it is best to use filtered, purified water with this system.
- Forced-air or bypass humidifiers - This final category of humidifiers is not a small, portable household appliance but a unit built into the furnace of buildings. They are also called bypass humidifiers because they are connected between the heated-air and cooled-air return ducts, using the pressure difference between these two ducts to cause some heated air to make a bypass through the humidifier and return to the furnace. As this type of humidifier is not applicable to most of our readers who use small, mobile humidifiers, we shall not discuss this system design in depth.
For Your Health, It Is Essential to Use Filtered, Purified Water in Humidifiers
Regardless of the type of humidifiers you currently use or plan to purchase, it is very important that you use only filtered, purified water in the humidifiers to protect your health and your family's health. It is also essential to clean the water-containing reservoir or tank frequently to ensure that there are no molds, bacteria, and other microorganisms growing and proliferating in the reservoir. Microorganisms can proliferate in containers that have not been cleaned and they will get propagated to the entire room or house along with fine water droplets. Additionally, when there is high mineral content in tap water or well water, the minerals will get projected out to the room or house along with water mist. Hence, for people with sensitive respiratory systems and various types of airborne allergies, breathing dust-filled (mineral-laden) air may not be good for their respiratory system and health in the long run. For the elderly and those with weakened immune systems, it is not good to breathe volatile chemicals and other allergens if they fill the humidifier's water reservoir with chemically contaminated water (such as well water or groundwater water polluted with hydrocarbons and pesticides). Volatile chemical compounds will get projected along with fine water droplets, causing health problems in the long term.
To Prolong the Life of Humidifiers, Use Filtered, Purified Water
Using filtered, purified water also has an added benefit of prolonging the life of humidifiers. Humidifiers—especially the impeller or ultrasonic types—project minerals in tap water or well water with high mineral content into the air. While people may breathe in the dust and see a layer of white dust on the surfaces in the vicinity of the humidifier, minerals in tap water may lead to crusty deposits, or scale buildup, in humidifiers. Scale can be a breeding ground for bacteria and other microorganisms. But scale also causes clogging and shortens the life of humidifiers. Hence, it is important to use filtered and purified water, which has its minerals filtered out during the filtration process, in the humidifiers. If consumers feel that filtered water is more expensive than tap water, then they should consider the alternative, of having to replace a humidifier more frequently due to clogging and crusty deposits. Buying a new humidifier is definitely more costly than using filtered water.
We recommend that regardless of the type of humidifier you currently use or plan to purchase in the near future, use only filtered, purified water to fill the reservoir or water-storage container. Also, clean the reservoir frequently. Remember, with humidifiers, if you want to breathe clean air, use clean water.