Through the Small Business Innovation Research (SBIR) program at NIEHS, we initiated a research project that will develop a comprehensive system to monitor and control indoor humidity and evaluate the efficacy of that comprehensive system in reducing levels of indoor allergens in homes.
Data from the National Survey of Lead and Allergens in Housing indicated that the strongest independent predictor of dust mite allergen levels is indoor humidity. Homes with relative humidity above 60% have 3-4 fold higher mean bed dust mite allergen than homes with relative humidity below 60%. Increased relative humidity is also associated with higher levels of cockroach and mold allergens.
Adequate control of humidity involves both moisture control (dehumidification) and improved ventilation. Remarkably, little is known regarding the best way to achieve these goals and no published studies have objectively evaluated the effectiveness of tight humidity control on indoor allergen levels.
The SBIR solicitation was published in 2004 and a contract was awarded. If proven efficacious, such a system would be utilized widely in clinical research studies and would be highly marketable given the high prevalences of asthma and other allergic diseases.