House dust mite allergens are a major cause of asthma. The objective of this study was preventing dust mite allergens in new houses with wall-to-wall carpets, not eradicating dust mites from infested homes.

Five pairs of homes, located in the southeastern U.S., were studied for an average of 12 months. Each pair consisted of a newly built home with a central dehumidifier and an existing home without a central dehumidifier. Three new homes and two existing homes had thorough vacuum cleaning practices. Dust samples were taken monthly from a minimum of four locations in each home and analyzed for mite allergen levels. Carpet level relative humidities and temperatures were measured. The dehumidification systems maintained the average carpet relative humidity (RH) below 60% in all five new homes for all months. The three new homes with dehumidification and thorough vacuum cleaning practices did not have any dust mite allergens at the beginning of the study and continued allergen free. The two new homes with a dehumidifier and the three existing homes with poor cleaning practices had high allergen levels. The two existing homes with thorough vacuum cleaning practices had high allergen levels on one occasion only.

Authors: Subrato Chandra, Ph.D., David Beal

Citation: Indoor Air Quality 2001 Moisture, Microbes, and Heath Effects: Indoor Air Quality and Moisture in Buildings Conference Papers

Keywords: November, California, 2001, IAQ