A Laboratory Comparison of Real-Time Measurement Methods for 10-100-nm Particle Size Distributions

• Published in: Aerosol science and technology 2014-05, Vol.48 (5), p.571-582
• Main Authors: Hornsby, K. E., Pryor, S. C.
• Format: Article
• Language: English
• Subjects: Aerosols; Airborne particulates; Atmospheric aerosols; Chemistry; Colloidal state and disperse state; Concentration (composition); Copyrights; Exact sciences and technology; General and physical chemistry; Measurement; Measurement methods; Nanostructure; Organic chemicals; Particle size distribution; Real time; Sizing
• ISSN: 0278-6826; 1521-7388
• DOI: 10.1080/02786826.2014.901488

We present information regarding the relative performance of five TSI particle sizing instruments when presented with several log-normally distributed particle populations that vary in terms of composition, concentration, and modal mean diameter (in the range of 10-100 nm) in a controlled laboratory environment. In experiments conducted with NaCl, NaNO 3 , and organic aerosols, across a total particle concentration suite ranging from approximately 1 × 10 4 cm −3 to 1 × 10 6 cm −3 , total number concentrations of sub-100-nm diameter particles from four SMPS systems and an FMPS all fall within ±50% of each other (and generally are within ±30%). However, larger discrepancies are evident in the particle size distribution, particularly for the NaCl particles, with an SMPS operated with a water-based CPC exhibiting large negative bias in modal peak concentrations relative to the isobutanol-based SMPS systems and the FMPS. Much closer agreement is found for NaNO 3 particles, although the SMPS systems tended to exhibit higher modal peak concentrations, and a slight shifting toward lower modal peak diameter than the FMPS. Copyright 2014 American Association for Aerosol Research