Exploring the potential for continuous measurement of ultrafine particle mass concentration (PM_0.1) based on measurements of particle number concentration above 50 nm (N₅₀)

Abstract

The real-time automatic and accurate measurement of the mass of ultrafine particles is especially challenging due to their low concentrations and the interferences of larger particles. This work introduces a new method to estimate PM_0.1 continuously. Based on the theoretical predictions of a 3-D chemical transport model, PM_0.1 and N₅₀ (number concentration of particles with a diameter above 50 nm) can have a very good correlation. This hypothesis is tested in this work by analyzing hourly measurements of size distributions, from different cities in Europe for a year. PM_0.1 had a strong spatial and temporal correlation with N₅₀ (R² > 90%). The line passing through zero had an average slope of 0.16 ± 0.01 × 10⁻⁹ µg, for an assumed particle density equal to 1 g cm⁻³. This suggests that PM_0.1 can be, at least in principle, measured indirectly but quite accurately and continuously by measuring N₅₀ with a suitable condensation particle counter.

Copyright © 2023 American Association for Aerosol Research

Editor:

• Jingkun Jiang

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data from this work are available upon request from Spyros Pandis ([email protected]).

Additional information

Funding

This work was funded by the project NANOSOMs Grant 11504 of the Greek HFRI.