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PM-Bound Polycyclic Aromatic Hydrocarbons

Monitoring of PM-Bound Polycyclic Aromatic Hydrocarbons from Diesel Vehicles by Photoelectric Aerosol Sensor (PAS)

  • Shida Tang, Robert Johnson, Thomas Lanni and William Webster
  • Automotive Emissions Laboratory
  • Bureau of Mobile Sources
  • Division of Air Resources
  • New York State Department of Environmental Conservation


In addition to the required measurement of particulate matter (PM) mass emission, characterization (chemical composition, surface area, size and number distributions) of diesel PM is becoming increasingly important and may impact future PM emission regulations. This is especially the case for PM-bound polycyclic aromatic hydrocarbons (PAHs), an organic class that includes many potential mutagenic and carcinogenic species. In this study, we have evaluated a sensor technique, photoelectric aerosol sensor (PAS), for the possibility of continuous monitoring of PM-bound PAHs. Evaluation of PAS is performed with heavy-duty diesel vehicles (trucks and buses) tested on a dynamometer with various transient driving schedules. Comparison study between PAS and standard chemical analysis of PAHs is also performed for a limited number of diesel and CNG buses. Validation of PAS has been carried out by analyzing the diesel particulate standard reference material SRM1650a with certified PAHs values from National Institute of Standards & Technology (NIST).

Plots of PAH mass emissions vs. speed (top), and vs. particulate mass determined by TEOM (bottom)
Real-Time PAH Mass Emissions for a 1994 Box Truck
Correlation plot of PAS readings vs. certified NIST values
Performance of PAS on NIST SRM 1650a