During the Innosuisse LCSS project (2019-2022), a difference of several orders of magnitude was observed in the values (mV) measured by the sensors during the outdoor campaign, despite full calibration in the laboratory beforehand. This project aims to find the explanation for this discrepancy, by participating in the 2023 ACTRIS ATMO ACCESS and using a semi-open atmospheric chamber in Spain (ACTRIS infrastructure: EUPHORE). This provides an intermediary solution between laboratory calibration and outdoor measurements. In the chamber, semi-controlled ambient air can be used.
