Receptor Modeling of Ambient Aerosol at an Elementary School in Las Vegas

Sonoma Technology scientists identified sources of ambient aerosol at an elementary school adjacent to a freeway in Las Vegas, Nevada, by applying the U.S. EPA’s positive matrix factorization tool (EPA PMF) on particles measured with an aerosol mass spectrometer. Using a data set of more than 2 million data points, we identified several local aerosol sources and determined how ambient concentrations vary by time of day and wind direction.
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EPA PMF error and diagnostic tools allowed us to easily
<ul>
<li>Evaluate factor stability</li>
<li>Resolve factors compared to known source profiles</li>