Discrete Grain Breakage (DGB) model is a fracture physics based model that describes fragmentation at the microscale level. In this paper, the authors describe the steps necessary to make the DGB model useful for comminution equipment performance simulations. In particular, a brief description of the code and recent improvements in efficiency required to make computation times reasonable are given. A method for obtaining fracture energy parameters from characterization tests is described. Methods to extend the technique to fine size simulations are discussed. Finally, a few example applications for commercial equipment are presented. (C) 2004 Published by Elsevier B.V.