Volatile organic compounds make up a very large group of chemical substances and are often sub-classified by boiling point temperature ranges which gives an idea of how likely it is to be found in liquid, solid, gaseous forms (or possibly more than one state) at various temperatures. The levels found in breathable air and how they affect air quality are strongly correlated with the boiling points. In general, the lower the boiling point, the higher the concentration that will be present in the air.
VVOC (Very Volatile Organic Compounds) Boiling points: less than 0 C to 100 C
VOC (Volatile Organic Compounds) Boiling points: 50 C – 260 C
SVOC (Semi-Volatile Organic Compounds) Boiling points 260 C – 380 C (includes many biocides)
POM (Particulate Organic Matter aka Solid Organic Compounds) Boiling points exceeding 380C includes PAHs (polycyclic aromatic hydrocarbon compounds)