Diploma thesis deals with experimental determination of explosion characteristics of wood Spruce (Picea abies), Red meranti (Shorea acuminata) and Summer Oak (Quercus robur) in a window and door manufacturing company. Aim of the thesis is to compare selected parameters of wood dust in milling, sawing and grinding processes. Lower dust explosion, bulk density, layer thickness, and fraction analysis on RETSCH AS 200 were experimentally determined on the dust samples. We tested samples in the VK 100 explosion chamber to determine the lower explosion limit. Summer Oak 20 g.m-3, Spruce 28 g.m-3 and Red meranti 23 g.m-3. Lowest values of the thickness dangerous layer were observing in the grinding processes. We have found that machining processes largely affect the lower explosion limit and the thickness of the hazardous layer of the examined wood dust. Based on the determination of the thickness of the dangerous layer, we determined that the dust of Summer Oak represents greatest risk of explosion and fire in the cultivation processing from the examined trees. We propose to take measures against the occurrence of fire and explosion in the form of organizational and technical possibilities specified in goverment regulation of Slovak republic 393/2006, about minimum requirements for improving the safety and health protection of workers potentially at risk from explosive atmospheres.