17 th European Symposium on Computer Aided Process Engineering – ESCAPE17 V. Plesu and P.S. Agachi (Editors) © 2007 Elsevier B.V. All rights reserved. 1 Functional Modeling for Risk Analysis Manuel Rodríguez a , José Luis de la Mata a a Autonomous System Laboratory -UPM,C/Jose Gutierrez Abascal, Madrid 28043, Spain; manuel.rodriguezh@upm.es Abstract This paper presents the use of functional modeling for risk analysis. Many methods exist to perform hazard analysis but they are not based on (explicit) models of the plant. The use of a model can help in having a semiautomatic and consistent way to perform the analysis. Besides the model can be, with little effort, reused in similar processes. A functional modeling methodolody is applied to a real process to prove the suitability of these techniques to perform risk analysis. Keywords: functional modelling, risk analysis 1. Introduction Process safety, accidents and environmental issues are increasing in importance in the process industry, and more due to public concerns and tighter regulations. Chemical and petrochemical plants and refineries are very complex processes that pose great challenges for the evaluation and the analysis of the hazards in them. Process plants are quite often operated at extreme pressure and temperature conditions in order to achieve a performance close to the optimum. This makes them more sensible and vulnerable to equipment failures.[1] Today every plant has to perform a hazard analysis of the process. This means to make a systematic way an identification, evaluation and mitigation of the potential risks of the process that can lead to safety and health dangers, and cause considerable economic losses.There are a lot of methods to perform the hazard analysis, methods such as: Checklists, What-If Analysis, Failure Modes