Attached please find the abstract for the next SOCAAR seminar.

The Secret Lives of Filters

Jeff Siegel 
Associate Professor  
Department of Civil Engineering
University of Toronto

Filters in forced air heating, ventilation, and air conditioning (HVAC) systems serve as passive sampling 
devices for airborne particles.  By analysing the dust that deposits on a filter, we can achieve better 
estimates of human exposure to particle-bound contaminants.  We have extracted and sequenced fungal 
and bacterial DNA from a wide variety of filters and see differences based on human occupancy patterns, 
building location, season, building type/use, and building age and history.  Additional results for heavy 
metals, phthalates, flame retardants, and other compounds suggest the value of this approach for a wide 
variety of particle-bound contaminants.  Combining dust extractions with assessments of the system run-
time, air flow rate through the filter, and the filter efficiency reveals a spatially and temporally integrated 
indoor concentration over the filter lifetime, which in turn provides a more robust picture of human exposure 
than traditional short-term air or settled-dust samples. This filter forensics approach has further value for 
exploring contaminant hot-spots and the spread of particle plumes.

April 3, 2013, 3 - 4 pm
Wallberg Building, 200 College Street, Room 407

This seminar will be recorded and will be available after the talk: 
http://www.socaar.utoronto.ca/collaboration/SOCAAR_Seminar_Series.htm
Recordings of past SOCAAR seminars can also be found here.