B.K. Ku, M. Eileen Birch
CDC/NIOSH, United States
pp. 585 - 587
Keywords: aerosolization, carbon nanotube, acoustic generator, aerosol
With increasing applications and global production of carbon nanomaterials, there is a growing concern about workplace exposure. The National Institute for Occupational Safety and Health (NIOSH) has recommended a working lifetime exposure limit (REL of 1 μg/m3, 8-h TWA, 45 years) to minimize the potential health risks associated with occupational exposure to carbon nanotubes and nanofibers (CNTs and CNFs) (NIOSH, 2013). Because of the large variety of CNT and CNF products, with varying physical and chemical properties (e.g., highly non-spherical fibrous structures), characterization of their properties and exposure risks is challenging. In addition to work processes, the inhalation risks of carbon nanomaterials depend on material properties, which affect both their toxicity and tendency for air dispersion (Ku et al., 2006). It is therefore important to investigate a variety of carbon nanomaterials to determine: 1) their potential for aerosolization, and 2) the residence time and size distribution of the generated aerosol particles. In this study, we investigated the aerodynamic behavior of CNT powders. The powders were aerosolized using an acoustic generator and their aerodynamic and mobility diameters were determined. Aerosol decay and the characteristics of particle generation were also investigated.