AeroSolfd: Advancing Air Quality through Retrofitted Gasoline Particulate Filters – Insights from Laboratory and Real-World Evaluations

The AeroSolfd project, an EU-funded initiative, aims to improve air quality by reducing particulate emissions from in-use light-duty vehicles (LDVs). In response to growing concerns over air pollution and its environmental and health impacts, the project focuses on retrofitting Gasoline Particulate Filters (GPFs) as a viable solution. A key component of the project was an in-depth measurement campaign conducted at the BFH Exhaust Emissions Test Center on four representative vehicles—two with direct petrol injection and two with intake manifold injection. The campaign assessed non-aged GPFs under laboratory conditions using the Worldwide Harmonized Light Vehicles Test Procedure (WLTC) and Steady State Cycle (SSC), as well as in real driving environments (RDE). Fourier-Transform Infrared Spectroscopy (FTIR) was used to analyze non-regulated emissions. The results demonstrated a significant reduction in particle numbers without adverse effects on gaseous emissions. Beyond controlled testing, the project implemented a large-scale field study by equipping vehicle fleets in Germany, Switzerland, Israel, and Denmark with GPFs and data loggers. These long-term investigations aim to assess real-world durability, efficiency, and potential secondary emissions after prolonged use. Preliminary findings confirm that retrofitted GPFs effectively reduce particulate emissions while maintaining vehicle performance. The ongoing fleet monitoring will provide further insights into their long-term benefits and practical feasibility. By demonstrating the effectiveness of GPF retrofits in both controlled and real-world conditions, AeroSolfd contributes to sustainable mobility and air quality improvements. The project provides a solid scientific basis for the wider implementation of GPFs as a cost-effective strategy to mitigate vehicular particulate emissions and support regulatory efforts toward cleaner urban environments.