Exposure assessment of nano-sized and respirable particles at different workplaces

Abstract

In this study, nanoparticle (NP, diameter \ 100 nm) and respirable particles measurements were conducted at three different nanopowder workplaces, including the mixing area of a nano-SiO 2epoxy molding compound plant (primary diameter: 15 nm), bagging areas of a nano-carbon black (nano-CB) (primary diameter: 32 nm) and a nano-CaCO 3 (primary diameter: 94 nm) manufacturing plant. Chemical analysis of respirable particle mass (RPM) and NPs was performed to quantify the content of manufactured nanoparticles in the collected samples. Nanopowder products obtained from the plants were used in the laboratory dustiness testing using a rotating drum tester to obtain particle mass and number distributions. The obtained laboratory data were then used to elucidate the field data. Both field and laboratory data showed that NP number and mass concentrations of manufactured materials were close to the background level. Number concentration was elevated only for particles with the electrical mobility diameter [100 nm during bagging or feeding processes, unless there were combustionrelated incidental sources existed. Large fraction of nanomaterials was found in the RPM due to agglomeration of nanomaterials or attachment of nanomaterials to the larger particles. From this study, it is concluded that RPM concentration measurements are necessary for the exposure assessment of nanoparticles in workplaces.

Characteristic of nanoparticles generated from different nano-powders by using different dispersion methods

“…A more harmonized approach for analyzing and reporting of the results was recommended (Brouwer et al 2009). In particular, few attempts have been made in establishing the practical relationship between measured dustiness and actual dust exposure at the workplace (Heitbrink et al 1990;Brouwer et al 2006;Tsai et al 2011).…”

Caracterización experimental de las emisiones de nanopartículas en el tratamiento de AA6061, AISI304 y Ti6Al4V por ondas de choque generadas por LASER

“…In addition to the LSP physical aspects relating to the generation and propagation of the shock waves transforming the target material, attention has to be given to the emission of nanoparticles during the process, following other similar studies performed on materials processing techniques such as surface processing and welding, aiming at the need to guarantee a safe workplace environment for operators (Buonanno et al, 2011;Tsai et al, 2011). The knowledge on the level of nanoparticles emitted during those processes is fundamental in order to be able to derive effective protection measures (Guerreiro et al, 2014;Albuquerque et al, 2015), so that the occupational exposure during industrial operations can be rather limited, thus contributing for a less harmful workplace environment.…”

Acid Mist Cyclone Separation Experiment on the Hydrochloric Acid Regeneration System of a Cold Rolling Steel Plant

“…Li et al (2015) established a new pressure drop model which indicates this pressure drop model was suitable for the cyclone splitters with pure or droplet-laden gases. Tsai et al (2004Tsai et al ( , 2007Tsai et al ( , 2011 remove nanoparticles in low pressure or vacuum conditions by an axial-flow cyclone. Quan et al (2009Quan et al ( , 2010 invented a new type of gas-liquid stripping equipment-the water jet air cyclone separator (WSA) which greatly improves the efficiency of the stripping of ammonia.…”