Measuring Real-World Vehicle Emissions: General Information
Faculty principal investigators:
- H. Christopher Frey, Associate Professor, Department of Civil Engineering, NC State (www4.ncsu.edu/~frey/)
- Nagui M. Rouphail, Professor, Department of Civil Engineering, NC State, (www.ce.ncsu.edu)
Dr. Frey’s research and teaching focus on air pollution and related subjects.
Dr. Rouphail’s research and teaching focus on transportation engineering and related subjects
Graduate Research Assistants
- Alper Unal, James Colyar, Nassir Uddin
All members of the project team are in the Department of Civil Engineering at NC State (www.ce.ncsu.edu). The department has approximately 40 faculty, 200 graduate students, and 500 undergraduate students.
This project is sponsored by the NC Department of Transportation
Collaborators in this work include the National Institute of Statistical Sciences. We are also providing extensive feedback to the vendor of the measurement equipment we are using, Clean Air Technologies International, Inc.
The primary objective of this project is to evaluate the effect of traffic signal timing and coordination (for several signals at multiple intersections) on vehicle emissions. The data from this project can be used to improve the design of signal coordination plans
We are using a new portable emissions measurement system, the OEM-2100 manufactured by Clean Air Technologies International, to collect vehicle emissions, engine, and speed data.
The OEM-2100 can be installed in a vehicle in about 15 minutes..
The OEM-2100 can be used in any gasoline-fueled vehicle that has an engine diagnostic link (typically 1990 and newer vehicles). All vehicles manufactured since 1996 use a standard interface.
NC State purchased the first OEM-2100 in July 1999
- More detailed information on the project is available at: http://www4.ncsu.edu/~frey/emissions/
- Measurements so far indicate that emissions are highest during accelerations for all pollutants measured.
- The number of accelerations during a trip is influenced by traffic signals. Thus, we are confident that we will show, through more extensive measurements and rigorous analysis, important links between traffic signal timing and emissions.
- Measurements so far, on a limited number of vehicles, indicate that emissions during idling are much lower than expected based upon previous computer models. One implication of this is that better coordination of traffic signals, to smooth traffic flow on highly traveled corridors, can be highly beneficial, even if it is at the expense of longer stop delays on cross-streets.
- You can influence your own emissions in positive ways by properly maintaining your car (tuneups and regular oil changes are important), and through how you drive. Avoid aggressive driving, which typically involves a lot of speed changes and “throttle snaps” -- this produces high emissions. Moderating accelerations can have a large effect on your emissions. When cruising, emissions tend to be lower if you can maintain a steady speed.
- We are continuing to conduct measurements on a variety of vehicles (e.g., sedans, pickups, minivans, sport utility vehicles) and on a variety of corridors (primarily in the Research Triangle region).
- Today (September 23, 1999) we are collecting data for highway and mountain road driving.
- We will update our web site on a periodic basis with descriptions of our work, photographs, sample results, driving suggestions, and other information that may be of general interest.
Measuring Real-World On-Road Vehicle Emissions: General Information