IAQ 2007, the Healthy and Sustainable Buildings conference organized by ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers), to take place in Baltimore on October 14^th – 17^th, will be discussing natural ventilation systems.

According to the organization’s press release, natural ventilation has been promoted as a cure-all to reduce cost and energy consumption and to improve indoor air quality and occupant comfort. The reality of natural ventilation, however, is more complicated. In the workshop, What’s So Great About Natural Ventilation, Steve Emmerich and Andy Persily, both with the National Institute of Standards and Technology, will discuss how natural ventilation systems relate to existing ventilation, thermal comfort and energy standards, and present experiences in Europe and Asia along with actual performance measurements. Other IAQ 2007 speakers on natural ventilation will join the workshop for a panel discussion on the topic.

“The design of natural ventilation systems for air distribution and reliability of ventilation rates over a range of weather conditions is more complex than many designers realize,” Emmerich said. “Also, issues of outdoor air quality, including moisture impacts, are not always addressed in system design.” Limited data is available on the performance of these systems in terms of outdoor air ventilation rates, thermal comfort parameters and indoor pollutant levels, according to Emmerich.