A Direct-Reading Particle Sizer with Elemental Composition Analysis for Large Inhalable Particles

By: James Sipich, Christian L’Orange, Kimberly Anderson, Christopher Limbach, John Volckens & Azer Yalin

Read the full article: https://www.tandfonline.com/doi/full/10.1080/02786826.2021.2002255

Aerosol particles with aerodynamic sizes within the range of ∼20–100 μm are currently difficult to measure, and available commercial instruments lack analyses for composition despite their relevance in the atmosphere, airborne disease transmission, and industrial processes.

Sipich et al. have developed a direct-reading particle sizer (DRPS) instrument capable of real-time sizing and elemental composition analysis of potentially inhalable hazardous industrial aerosols with size range of ∼20–100 μm. The system is based on time-of-flight and Mie scattering of laser light to measure particle sizes as they pass a pair of vertically aligned laser beams. Elemental composition was achieved by a complimentary laser induced breakdown spectroscopy (LIBS) laser pulse. The authors demonstrated that the relationship between median aerodynamic diameters of particles measured by the DRPS time-of-flight and optical microscopy comparison was linear (Deming regression slope of 0.998) and strongly correlated (r2 > 0.999). The authors aim to validate the extended capabilities of the system with numerical simulations and improved detection efficiency for field use.