Aim of this paper was to investigate the effects of grit size and wood species on mass concentration and size distribution of wood dust produced by hand-held belt sander. Experimental study was designed as 2x2 full factorial experiments. Experimental parameters and their levels were abrasive grain size (P80, P120) and wood species (European beech (Fagus sylvatica L.), Norway spruce (Picea abies)).The mass concentration of emitted wood dust was measured using aerosol monitor (TSI Inc., DustTrak DRX 8533). Sampler head was sited in place representing breathing zone of operator of sander. The results was analysed employing the analysis of variance (ANOVA) with 5% of significance level. Real-time measurements demonstrated that spruce wood generated higher dust concentrations than beech wood due to difference in abrasion durability. Compared to sanding belt with P80 grit size, approximately 16%-32% higher dust concentration was generated when the sanding belt with P120 grit size was used.
 M. Alonso-Sardón, A.J. Chamorro, I. Hernández-Garcia, H. Iglesias-de-Sena, H. Martín-Rodero, C. Herrera, M. Marcos and J.A. Mirón-Canelo. “Association between Occupational Exposure to Wood Dust and Cancer: A Systematic Review and Meta-Analysis”. Plos One, vol. 10, no. 7, 2015.
 J. Douwe, K. Cheung, B. Prezant, M. Sharp, M. Corbin, D. McLean, A. Mannetje, V. Schlunssen, T. Sigsgaard, H. Kromhout, A. LaMontagne, N. Pearce and J. McGlothlin. “Wood Dust in Joineries and Furniture Manufacturing: An Exposure Determinant and Intervention Study”. Annals of Works Exposures and Health, vol. 61, no. 4, pp. 416-428, 2017.
 F.X. Keller and F. Chata. “Characterization of wood dust emission from hand-held woodworking machines”. Journal of Occupational and Environmental Hygiene, vol. 15, no. 1, pp. 13-23, 2018.
 P. Koleda and P. Koleda. “Optical measurements of sawdust dimensions”. Wood Research, vol. 61, no. 3, pp. 505-512, 2016.
 J. Krilek, J. Kováč, Š. Barcík, J. Svoreň, M. Štefánek and T. Kuvik. “The influence of chosen factors of a circular saw blade on the noise level in the process of crosses cutting wood”. Wood Research, vol. 61, no. 3, pp. 475-486, 2016.
 Marková, E. Mračková, A. Očkajová and J. Ladomerský. “Granulometry of selected wood dust of dust from orbital sanders”. Wood Research, vol. 61, no. 6, pp. 983-992, 2016.
 Očkajová, A. Beljaková and J. Ľuptáková. “Selected properties of spruce dust generated from sanding operations”. Drvna Industrija, vol. 59, no. 1, pp. 3-10, 2008.
 J. Ojima. “Generation rate and particle size distribution of wood dust by handheld sanding operation”. Journal of Occupational Health, vol. 58, no. 6, pp. 640-643, 2016.
 J. Ratnasingam, F. Scholz, V. Natthondan and M. Graham. “Dust-generation characteristics of hardwoods during sanding processes”. European Journal of Wood and Wood Products, vol. 69, no. 1, pp. 127-131, 2011.
 J. Rončka and A. Očkajová. “The influence of sanding machine type and grit size on granularity of sanding wood dust”, in Proc. of the 2nd ISC-Woodwoking techniques, 2007, pp. 289-294.
 STN EN 50632-2-4:2013. Electric motor-operated tools. Dust measurement procedure. Part 2-4: Particular requirements for sanders other than disk type.
 Thorp and R. Brown. “Factors influencing the production of dust during the sanding of wood”. American Industrial Hygiene Association Journal, vol. 56, no. 3, pp. 236-242, 1995.
 Welling, M. Lehtimäki, S. Rautio, T. Lähde, S. Enbom, P. Hynynen and K. Hämeri. “Wood Dust Particle and Mass Concentrations and Filtration Efficiency in Sanding of Wood Materials”. Journal of Occupational and Environmental Hygiene, vol. 6, no. 2, pp. 90-98, 2009.
 R.E. Wiggans, G. Evans, D. Fishwick and C.M. Barber. “Asthma in furniture and wood processing workers: a systematic review”. Occupational Medicine, vol. 66, pp. 193-201, 2016.
 D.E. Young-Corbett and M.A. Nussbaum. “Dust Control Effectiveness of Drywall Sanding Tools”. Journal of Occupational and Environmental Hygiene, vol. 6, no. 7, pp. 385-389, 2009.
 A.T. Zimmer and A.D. Maynard. “Investigation of the aerosols produced by a high-speed, hand-held grinder using various substrates”. The Annals of Occupational Hygiene, vol. 46, no. 8, pp. 663-672, 2002.