Impact of Residential HVAC Filters on Particle Concentration and Exposure

Abstract

Filters in heating, ventilating, and air conditioning (HVAC) systems can improve indoor air quality. In North America, residential air cleaning is usually done by recirculating indoor air through a filter. In this work, I explored two methods of assessing the impacts of HVAC filters in residences. The first method was through examining year-long PM measurements in 20 Toronto homes where different types of filters were installed. I found no evidence that higher efficiency filters reduced long-term exposure to PM. The second method was by studying the particle size distribution of filter dust. I explored the possibility of size separating filter dust to gain more information on smaller particles. One major challenge is the sticky nature of filter dust makes both the separation and mixing (with water for size analysis) processes difficult. Despite the caveats, these findings suggest that both methods are promising and can provide useful information for future studies.