Risks of Spruce Wood Dust in the Work Environment

This study investigated spruce wood (Picea abies Karst. L.) dust generated during sanding in a woodworking company, focusing on its health, explosion, and fire hazards. Microscopic analyses revealed that dust particles ranged from 2.38 μm × 1.69 μm to 499.71 μm × 403.30 μm, with an average size of 73.2 μm × 37.98 μm. Smaller particles exhibited a spherical morphology, while larger ones were elongated and fibrous. Sieve analysis confirmed that particles sized 63–75 μm formed the largest fraction (46.74%), with 71% of the total dust being airborne (<100 μm), including 5% PM10 and 1% PM2.5. Explosion tests identified a lower explosion limit (LEL) of 80 g·m−3, with dust classified as highly explosive (ST 2). Smaller particles were found to significantly reduce the LEL, increasing explosion susceptibility. These findings highlight the dual risk of inhalation exposure and explosion potential. Practical safety recommendations include ensuring efficient local dust extraction, mandatory use of respiratory protection, and restricted worker movement near sanders. Furthermore, organizational measures aligned with ATEX standards—such as daily cleaning, removal of settled dust layers, use of explosion-safe industrial vacuum cleaners, and installation of automatic explosion suppression systems in extraction units—are essential.