Currently, the Sulphur-Iodine thermochemical cycle, used in the hydrogen production process, is receiving increased research and development focus. The operating conditions of this process are generally hazardous by virtue of the intrinsic chemical properties of the materials used in the process. Of particular concern, is their operating temperature, pressure, or a combination of these. In order to determine the possible areas affected due to a hazardous release, simulations were performed using the Phast computer program. In particular, release scenarios of sulphuric acid, sulphur dioxide, sulphur trioxide, iodine, and hydriodic acid were studied in order to design and implement safety measures to protect the facility, the environment, and the population. Also contained within this study are recommendations for the locations of gas sensors for emergency systems, as well as suggested methods to determine plant layout design and exclusion zones. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.