With the growth of the petrochemical industry, confined space evacuation has been a major safety issue due to the potential fatalities and injuries caused by inadequate emergency response. In this work, two existing software, BuildingEXODUS and FDS1Evac, were used to simulate the required safe egress time (RSET) in different evacuation environments. Vertical and horizontal storage tanks were constructed using these two simulation software. Then, different parameters such as occupant load, with and without internal obstruction, and exit size were studied in different simulation scenarios. The simulation results from the software have shown good agreement with those from field experiments. It was found that the RSET of a vertical storage tank is nearly half of that of a horizontal storage tank. The work has demonstrated that the fire safety software could be used to simulate evacuations from confined spaces in petrochemical facilities. (C) 2015 American Institute of Chemical Engineers