title: A method for measuring particle number emissions from vehicles driving on the road.
abstract: Earlier research has demonstrated that the conditions of dilution of engine exhaust gases profoundly influence the size distribution and total number of particles emitted. Since real world dilution conditions are variable and therefore difficult to simulate, this research has sought to develop and validate a method for measuring particle number emissions from vehicles driving past on a road. This has been achieved successfully using carbon dioxide as a tracer of exhaust gas dilution. By subsequent adjustment of data to a constant dilution factor, it is possible to compare emissions from different vehicles using different technologies and fuels based upon real world emission data. Whilst further optimisation of the technique, especially in terms of matching the instrument response times is desirable, the measurements offer useful insights into emissions from gasoline and diesel vehicles, and the substantial proportion of particles emitted in the 3-7 nanometre size range.
authors.affiliation: Division of Environmental Health and Risk Management, The University of Birmingham, Edgbaston, United Kingdom.
authors.forename: J P
authors.initials: JP
authors.lastname: Shi
authors.forename: R M
authors.initials: RM
authors.lastname: Harrison
authors.forename: D E
authors.initials: DE
authors.lastname: Evans
authors.forename: A
authors.initials: A
authors.lastname: Alam
authors.forename: C
authors.initials: C
authors.lastname: Barnes
authors.forename: G
authors.initials: G
authors.lastname: Carter
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D002245:Carbon Dioxide / Q000032:analysis; D004784:Environmental Monitoring / Q000379:methods*; D007201:Indicator Dilution Techniques; D010316:Particle Size; D001335:Vehicle Emissions / Q000032:analysis*
chemical_list: D000393:Air Pollutants; D001335:Vehicle Emissions; D002245:Carbon Dioxide