Designing a safe and economical mining activity is the main goal of every mine design engineer. With the rise of computer modeling in mine design there is a need for a standardized method to use geologic characterization of rocks in engineering design. In this research, first a review of empirical methods will be conducted and after that a step-by-step method is presented to adequately use FLAC3D, for development pillars, in room and pillar mine in development stage. ARMPS database is used to evaluate the FLAC3D model results. ARMPS database consists of 645 case study in room and pillar mines. 170 of them are mines in development phase. In this research all 170 cases will be analyzed in FLAC3D v4.0 and the results will be compared to actual success and failure from the database. Also, the stability factor found from FLAC3D will be compared to ARMPS. Finally, it is tried to calibrate FLAC3D stability factor so it can be used in room and pillar design.