Humidifiers are commonly used in homes to relieve the physical discomforts of dry nose, throat, lips and skin. The moisture they add to dry air also helps alleviate common nuisances brought on by winter heating. However, excess moisture can encourage the growth of biological organisms in the home. These organisms include dust mites and molds.
University of Illinois Extension and the U.S. Environmental Protection Agency says that the four main types of humidifiers are ultrasonic, which create a cool mist by means of ultrasonic sound vibrations; impeller, which produce a cool mist by means of a high speed rotating disk; evaporative, which transmit moisture into the air by using a fan to blow air through a moistened absorbent material; and steam vaporizers, which create steam by heating water with an electrical heating element or electrodes.
Proper care and cleaning of ultrasonic and impeller humidifiers are important for reducing potential exposures to microorganisms, such as bacteria and molds.
- Empty the tank, wipe all surfaces dry and refill the water in portable humidifiers daily to reduce any growth of microorganisms. Be sure you unplug the unit from the electrical socket first.
- Use water with low mineral content to prevent the buildup of scale and the dispersal of minerals into the air.
- Clean portable humidifiers every third day. Empty the tank and use a brush or other scrubber to clean it. Wipe all surfaces dry. Again, be sure you unplug the unit.
- Follow the manufacturer’s suggestions on the use of cleaning products or disinfectants. In the absence of specific recommendations, clean all surfaces coming in contact with water with a 3 percent solution of hydrogen peroxide. If you use any cleaning or disinfecting agent, rinse the tank thoroughly with several changes of tap water to prevent dispersal of chemicals into the air during use.
- Follow the manufacturer’s directions on cleaning and maintaining console and furnace mounted humidifiers. In particular, if the humidifier contains a tank, do not allow water to stand in the tank for extended periods of time, and keep the water clean.
- Do not humidify to indoor relative humidity levels exceeding 50 percent. Higher humidity levels may encourage the growth of biological organisms in the home. If water condenses on windows, walls or pictures, either relocate the humidifier, lower its humidistat setting or reduce its use.
- Do not permit the area around the humidifier to become damp or wet. If dampness occurs, turn the output volume of the humidifier down. If the humidifier output volume cannot be turned down, use the humidifier intermittently. Do not allow absorbent materials, such as carpeting, drapes or tablecloths, to become damp.
- Follow the manufacturer’s instructions regarding the use, maintenance and replacement of any materials supplied with the humidifier. Use appropriate materials as recommended by the product manufacturer.
- Clean the humidifier, as directed, at the end of the humidifying season or when the product will not be in frequent use. Before storage, make sure all the parts are dry. After storage, clean the unit again and remove any dust on the outside.