Remote Sensing Instrument for On-Road Heavy-Duty Diesel NOx and PM Emissions

EPA Contract Number: 68D01007
Title: Remote Sensing Instrument for On-Road Heavy-Duty Diesel NOx and PM Emissions
Investigators: McManus, J. Barry
Small Business: Aerodyne Research Inc.
EPA Contact: Manager, SBIR Program
Phase: I
Project Period: April 1, 2001 through September 1, 2001
Project Amount: $70,000
RFA: Small Business Innovation Research (SBIR) - Phase I (2001) RFA Text |  Recipients Lists
Research Category: Ecological Indicators/Assessment/Restoration , SBIR - Monitoring , Small Business Innovation Research (SBIR)


Emissions of nitrogen oxides (NOx) and particulate matter (PM) from motor vehicles contribute to a variety of environmental problems, including photochemical smog formation, acid deposition, visibility reduction, and adverse health effects. As the emissions from passenger cars and light-duty trucks have become more tightly controlled, the relative importance of heavy-duty diesel trucks (HDDTs) as a source of PM and NOx has greatly increased. The U.S. Environmental Protection Agency (EPA) recently has proposed regulations that would substantially reduce PM and NOx emissions from HDDTs starting in 2007.

To assess the effectiveness of controls, new techniques are needed to measure emissions from in-use diesel vehicles. Remote sensing of on-road vehicle pollutant emissions is a powerful technique for evaluating real-world automotive and truck emissions. Thousands of vehicles can be inspected by a single instrument during 1 day. Aerodyne Research, Inc., previously has demonstrated a tunable infrared laser spectrometer that remotely senses gaseous emissions, including NOx, from HDDTs with exquisite sensitivity and selectivity. This proposal would extend the capability of this method to include measurements of PM by remote sensing.

The proposed method for PM measurements will use a multiple-wavelength opacity method to determine the mass density of black carbon soot emitted by HDDTs. This approach will probe the exhaust plumes of passing HDDTs with several coaligned laser beams with a wide range of wavelengths, from the mid-infrared to the visible. All of the beams will sample the same absorption path through the plume, simultaneously measuring several column densities. The opacities at this wide range of wavelengths will be used to derive the (column) mass density of black carbon (soot).

The integration of NOx and PM monitoring techniques into one instrument will provide a powerful tool for survey measurements of HDDTs. Optical remote sensing enables measurements of vehicle emission characteristics in real-world situations, covering the mix of vehicles and engine loads encountered in normal driving. The capability to measure both NOx and PM with a single instrument will enable accurate inventories of HDDT emissions to be obtained under actual usage conditions.

The capability to measure PM that will be developed in this proposal will greatly enhance the commercial success of an integrated instrument. The recently proposed EPA regulations for HDDT emission controls will require this type of monitoring equipment for evaluation of present HDDT fleet emissions, verification of compliance for individual vehicles, and validation of the success of the program.

Supplemental Keywords:

small business, SBIR, monitoring, emissions, diesel, NOx, PM, engineering, chemistry, EPA, vehicle emissions, remote sensing., RFA, Scientific Discipline, Air, Sustainable Industry/Business, particulate matter, air toxics, Chemistry, mobile sources, New/Innovative technologies, tropospheric ozone, Engineering, Engineering, Chemistry, & Physics, Environmental Engineering, remote sensing, heavy-duty, soot , smog, emissions, trucks, photochemical, diesel

Progress and Final Reports:

  • Final
  • SBIR Phase II:

    Remote Sensing Instrument for Particulates and NOx From Heavy-Duty Diesel Vehicles  | Final Report