###### Abstract
In order to minimize dust emission during the abrasive sanding process of hardwoods, they recommended the use of the coarsest possible abrasive grit and lowest possible wood removal rate. [PERSON] et al. [20] performed granulometric analysis of wood dust samples from oak, beach, spruce, alder and fir. Wood dust samples were obtained through an orbital sander with a grit size of P80. They found that the most frequent percentages of dust particles (between 50 and 79%) in all samples of wood dust were fractions of 32 \(\upmu\)m and less. [PERSON] et al. [21; 22] compared the granulometric compositions of sanding wood dusts of selected wood species (beech, oak) and determined the influence of various factors (type of sander, wood species, sandpaper grit size, and sanding direction) on percentage fractions less than 80 \(\upmu\)m. The results confirmed that the use of hand-held sanders caused high percentages of fractions less than 80 \(\upmu\)m, above 90% in all cases. In another study conducted by [PERSON] et al. [23], sieve analysis was performed for sanding dust from thermally modified wood (oak, spruce, and mernanti). The results indicated that the share of wood dust particles with a size less than 80 \(\upmu\)m was similar in unmodified and thermally modified wood. [PERSON] et al. [24] carried out granulometric analysis of selected samples of tropical wood dust from cumaru, padauk, ebony, and marblewood. Tropical wood dust samples were obtained using a disc sander. In addition, the size and shape of wood dust particles were studied by microscopic analysis. Results of granulometric fractions contribution confirmed that the majority of dust particles were under 100 \(\upmu\)m in size. [PERSON] et al. [25; 26] used two complementary methods, sieve analysis and laser diffraction analysis, to determinate the particle-size distribution and content of very fine particles during the sanding of selected wood species. They found that the type of wood (hardwood or softwood) had a significant influence on the mean arithmetic dust size and the content of the dust fraction with a size \(<\)10 \(\upmu\)m. [PERSON] [27] investigated the generation of wood dust during the sanding of two different wood species (beech and cypress) with three different grit sizes (coarse, medium and fine)of the sanding paper by a hand-held orbital sander. The particle size distribution of the wood dust was measured by an eight-stage Andersen cascade impactor. The morphology of the wood dust particle was observed by a desktop digital microscope. [PERSON] found that when specimens were sanded with a fine paper, the mass median aerodynamic diameters of beech dust and cypress dust were 9.0 \(\upmu\)m and 9.8 \(\upmu\)m, respectively. [PERSON] et al. [28] performed measurements of wood dust mass concentration using a direct-reading aerosol monitor that combined a light scattering photometer and optical particle counter. The results of real-time measurements demonstrated that softwood species generated higher dust concentrations than hardwood species due to a difference in abrasion durability. According to the findings reported in the literature, little attention has been given to the UFP generated during wood sanding tasks. There is an assumption that nanoparticles could be an important part of total dust mass, number, and surface area concentration in workplaces involving a wood sanding process [29]. Measurement strategies for exposure to UFP differ from traditional integrated sampling methods for exposure assessments, by the use of real-time instruments [30]. A range of metrics and hence measurement instruments are currently used, because there is no legally enforceable nano-specific occupational exposure limit for wood dust. At the current confusing state whereby metrics of nanoparticles are correlated with specific toxicological end points, it might very well turn out that different particle metrics are correlated with different health end points [31].