Measurement report: Evaluation of the TOF-ACSM-CV for PM 1.0 and PM 2.5 measurements during the RITA-2021 field campaign

• Published in: Atmospheric chemistry and physics 2024-03, Vol.24 (6), p.3405-3420
• Main Authors: Liu, Xinya, Henzing, Bas, Hensen, Arjan, Mulder, Jan, Yao, Peng, van Dinther, Danielle, van Bronckhorst, Jerry, Huang, Rujin, Dusek, Ulrike
• Format: Article
• Language: English
• ISSN: 1680-7324; 1680-7324
• DOI: 10.5194/acp-24-3405-2024

The recently developed time-of-flight aerosol chemical speciation monitor with a capture vaporizer and a PM2.5 aerodynamic lens (TOF-ACSM-CV-PM2.5) aims to improve the collection efficiency and chemical characterization of aerosol particles with a diameter smaller than 2.5 µm. In this study, comprehensive cross-comparisons were performed between real-time online measurements and offline filter analysis with 24 h collection time. The goal was to evaluate the capabilities of the TOF-ACSM-CV-PM2.5 lens, as well as the accuracy of the TOF-ACSM-CV-PM2.5. The experiments were conducted at Cabauw Experimental Site for Atmospheric Research (CESAR) during the RITA-2021 campaign. The non-refractory fine particulate matter (PM1.0 and PM2.5) was measured by two collocated TOF-ACSM-CV-PM2.5 instruments by placing them behind a PM2.5 and PM1.0 inlet, respectively. A comparison between the ACSMs and PM2.5 and PM1.0 filter samples showed a much better accuracy than ±30 % less given in the previous reports, with average differences less than ±10 % for all inorganic chemical species. In addition, the ACSMs were compared to the Monitoring Instrument for Aerosol and Gas (MARGA) (slope between 0.78 and 0.97 for inorganic compounds, R2≥ 0.93) and a mobility particle size spectrometer (MPSS), measuring the particle size distribution from around 10 to 800 nm (slope was around 1.00, R2= 0.91). The intercomparison of the online measurements and the comparison between the online and offline measurements indicated a low bias (