The measurement of vehicle exhaust gas emissions for national inventories and highway impact studies

• Published in: The Science of the total environment 1987, Vol.59, p.63-76
• Main Author: Potter, C.J.
• Format: Article
• Language: English
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/0048-9697(87)90431-1

The contribution of motor vehicles to the atmospheric burden of pollutants is strongly dependent on the traffic activity and average speed. The use of emission factors which are derived from legislative test procedures to calculate emission inventories is limited by the prescribed test drive and may result in errors. More realistic emission factors can be obtained by testing vehicles on the road over a wide range of operating conditions such as urban, suburban and motorway drives and reproducing these drives on a chassis dynamometer. However, the development of a mini-CVS system which can be used on-board vehicles and thus obtain a proportional sample of the exhaust gases during a test drive on the road facilitates the direct measurements of emissions. This development and its validation will be briefly described. The use of the mini-CVS system in a survey of the emissions of twenty cars driven on the public highway will be described. Also, the emission of conventional engined cars and a 3-way catalyst equipped car when driven at high speeds will be reported.