Innovative Emissions Measurement and Perspective on Future Tailpipe Regulation

The Euro 7 exhaust emissions regulation will be important both from the perspective of how it further improves air quality, but also of certain greenhouse gas emissions and the economics of the internal combustion engine. This paper sets out the ongoing importance of ozone to urban air quality, and how tailpipe volatile organic compound (VOC) emissions contribute to that as well as having direct human health effects through inhalation. The paper then sets out a novel method for the measurement of speciated VOCs and nitrous oxide (N2O) at the tailpipe in real-world conditions, and presents initial results across a range of modern light-duty vehicles. Based on the results, it may be the case that VOCs should be a higher priority for future regulation than N2O, although more research is required to achieve a consensus on typical real-world N2O emissions.