Evaluating the Contribution of PM2.5 Precursor Gases and ...

PAH: Polyaromatic Hydrocarbon. This is a subset of POM (Polycyclic Organic Matter), and VOC (Volatile Organic Compounds). PM2.5: Particulate matter that is less than or equal to 2.5 micrometers in diameter. PM2.5 Precursor: Any chemical that contributes to the formation of PM2.5 particles, but is not emitted directly from a source as PM2.5.

  Hydrocarbon, Precursors, 5 precursor