An approach to the correlation of maximum explosion overpressure to parameters available at process plants is presented. A database of CFD explosion simulations of process plants performed by DNV as well as published experiments forms the bases for developing the correlation. Process area designs with corresponding explosion overpressure results were categorized and analysed to select available and well defined parameters which have a significant impact on the overpressure. Some definite trends were obtained and used to develop correlations and explicit equations which provided explosion overpressures as a function of the selected parameters. The trend for cloud size is presented in this paper together with an overall comparison of the correlation with experiments and CFD simulations. This paper further presents the critical parameters as well as results from applying the correlations to find inherently safe arrangements and designs of process areas. (C) 2009 Elsevier Ltd. All rights reserved.