Damage or failure in wood composite is clarified in three-difference scale, which are macroscopic scale, meso-scale and microscopic scale. A macroscopic scale is an observation on visible failure such as knots and pinholes. The meso-scale is an observation on defects of the grain that causes changes in material axes and structural properties. Lastly is the microscopic scale. The microscopic scale is an observation on fibrous structure of the material. The screw fixing damages were classified under the macroscopic scale defects. In the terms of mechanics of wood and wood composites, the absence of failure is necessary for the safety purposes Fracture behaviour for particleboard is different compared to solid wood. Fracture behaviour of wood is determine by wood orientations while the fracture behaviour of the particleboard is determine by the adhesion of the particle
