Trend on Automotive Emission Regulations and Their Related Measurement Technologies

Abstract

The vehicle emission regulations have been driving forces for advancing the technologies of vehicle engines, and have led to the drastic reduction of pollutant emissions from each vehicle. However, the increasing number of vehicles in the world still causes many issues need to be solved, e.g. air quality, climate change, and energy consumption. Therefore, the emission limits and fuel economy standards are being tightened year by year. As recent topics, new regulations, such as particle number (PN) in EU countries and greenhouse gas (GHG) emission in US, have been enforced. In addition, the Worldwide harmonized Light vehicles Test Procedure (WLTP) has been issued by UNECE/WP.29. The test procedures and measurement conditions defined in EU regulations will be revised in the near future, in response to increasing interest in real-world emission (RDE). New procedures or regulations sometimes require updating measurement techniques. This article gives an outline of emission regulation trends for light-duty vehicles and introduces advanced emission measurement technologies from the view-point of relation with such regulations.