Policy development to design buildings and ventilation systems to preserve good indoor air quality

“Transit Oriented Development” and “Smart Growth” are two prevalent planning policies that potentially subject the residents of new residential construction to significant roadway related air pollution. In addition many existing residents who live near freeways, high traffic roadways, and stationary air pollution sources are subjected to significant air pollution in their existing homes. Research indicates that the concentration of particulates outdoors fully penetrates the indoor environment in buildings with leaky building envelopes or with open windows and doors. Available mitigation technologies including weatherization and/or installation of air filtration systems have the potential to mitigate outdoor air pollution impacts on indoor air quality for both new and existing sensitive residential uses in air pollution “hot spots”. Mechanical ventilation and associated filtration has been found to be effective in significantly reducing outdoor particulate matter in indoor air. In 2008 San Francisco passed a local ordinance that required all new residential construction exposed to significant roadway particulate matter to install filtration systems. Community risk reduction plans are underway to develop filtration based mitigation strategies in existing residential structures located in air pollution “hot spots”. The success of these filtration based strategies requires that the outdoor to indoor penetration of air pollutants be minimized by maintaining a tight exterior building shell. Similar “tight shell” strategies can be found in both weatherization design for energy conservation and acoustical design for noise control. In this manner green building practices can contribute to public health through reduced air and noise pollution.