This project is a second contract under the framework contract "Assessment of environmental impacts framework contract – Research on characteristics of aircraft engine emissions" of the SAMPLE IV consortium funded by the European Aviation Safety Agency (EASA). The tasks of the second (and final) specific contract (SC02) are: Elaboration of proposals for improved and novel nvPM measuring concepts. Impact assessment of nvPM emissions from non-regulated engines and selection of engines for emission measurements. Planning and performance of the non-regulated engine emissions tests. Development of proposals for a more accurate correlation between SN and nvPM mass and between nvPM mass and number. Development of recommendations on updates to the certification of fuel specifications.