Pirmary and Secondary emissions from Euro6 vehicles are here presented. Diesel cars were characterized by the emission of high quantities of NOx and low quantities of black carbon (BC). The diesel passenger car exhibited very low VOCs emission factors (EFs) compared to the diesel commercial vehicle, especially during the cold urban cycle. On the contrary, gasoline Euro6 vehicles emitted low quantities of NOx, but high BC and VOCs, particularly during the cold start of the engine. Both gasoline vehicles were characterized by high monoaromatics EFs. Results will be discussed in term of technology and fuel type.

This study examines direct particle emissions and secondary aerosol formation from three Euro 6 light-duty vehicles: a gasoline vehicle with a particulate filter, a diesel vehicle with a particulate filter, and a CNG vehicle without a filter. Measurements were taken during repeated 1-hour driving cycles. Results showed the highest direct emissions from the CNG vehicle and the highest secondary organic aerosol formation from the diesel vehicle. The study highlights the need for further research on unregulated emissions, particularly for Euro 6 CNG vehicles, to better understand their impact on air quality and human health.

This study explores the influence of fuel, engine technology and aftertreatment systems on the secondary aerosol formation potential from exhaust emissions by light-duty (LD) traffic.

Since 2022, several European countries have added a particle number (PN) test in the PTI of diesel vehicles equipped with DPF, the so-called PN-PTI test. This study examines five different testing procedures for PN-PTI testing of gasoline vehicles and compares PN-PTI emissions with type-approval PN emissions tested with the worldwide harmonized light vehicles test cycle (WLTC).

Ultrafine particles (UFP) and gaseous pollutants emitted from vehicle exhausts are major contributors to air pollution in urban areas. In the EU, the number of solid exhaust particles is regulated for on-road type approval of vehicles by testing real driving emissions (RDE) using portable emissions measurement systems (PEMS). However, compared to reference instruments used in laboratory testing, PEMS have larger measurement uncertainty due to simpler design, while metrological validation of PEMS is currently lacking. This work studied the performance and uncertainty of PEMS in laboratory and RDE test to underpin the current and future conformity factors.

This study presents an updated emissions inventory for Thessaloniki, Greece, focusing on particulate matter emissions from road transport. Using high-resolution vehicle speed data, spatiotemporal emission profiles were developed and compared with static ones. Results show reduced emissions during summer months and distinct diurnal peaks, especially in the city center and eastern residential areas, contrasting with static profiles. Both inventories are integrated into an air quality modeling system to assess their impact on aerosol concentration simulations, highlighting the importance of dynamic traffic data in urban air quality management.