Data in the newly releasedAirAdvice State of Our Indoor Air Report 2007shows that nine out of 10 homes have indoor air quality (IAQ) problems. The report’s findings are based on AirAdvice Inc.’s analysis of 49,130 indoor air quality tests conducted in homes across North America in cooperation with a network of more than 1,500 HVAC professionals.

Overall, 96.7% of all homes tested had at least one of six IAQ problems - particle allergens, chemical pollutants, carbon dioxide, temperature, humidity and carbon monoxide.

Most homes had multiple indoor air problems. Eighty-three percent of all homes tested exhibited two or more of the six problem types; nearly half (49.8%) had three or more problems; 18.9% had four or more.

The report gives HVAC contractors detailed statistics and information on IAQ problems, as well as helpful information for contractors’ customers. Highlights from the 28-page report include:

  • The most common IAQ problem in North American homes is particle allergens, with over 91% of homes showing elevated allergen levels.

  • Elevated chemical pollutant (volatile organic compound) levels were found in seven out of 10 homes (70%).

  • Carbon dioxide, temperature and humidity levels were outside recommended ranges in many homes - in 45%, 30% and 49% of cases, respectively.

  • Carbon monoxide was found at elevated levels in 2% of homes.

    The AirAdvice State of Our Indoor Air Report 2007 is available for download at Or, visit for additional IAQ resources and information.