The explosion ability of wood dust was characterized by a 20 L explosion sphere (Kuhner). The overpressure inside the sphere is recorded during the explosion. The results show that the violence of the explosion is all the more important that the particle size is low. A model based on balances on chemical reaction, kinetics and thermodynamics leads to the representation of the pressure change during the explosion. There is a good agreement between the calculations and the experiments. (c) 2005 Elsevier B.V All rights reserved.