EFFECTS is advanced software to assist you in performing safety analysis for the (petro)chemical industry throughout the whole chain, from exploration to use. It calculates the effects of the accidental release of hazardous chemicals, allowing you to take steps to reduce the risks involved. EFFECTS performs calculations to predict the physical effects (gas concentrations, heat radiation levels, peak overpressure's etc.) of the escape of hazardous materials. Results are presented in either textual or graphical format. Models in EFFECTS are based upon the Yellow Book, third edition, second print 2005 or may have been adapted to more recent theoretical insights. Background information about the source of the model is provided through the menu option "Help"- "Model documentation". EFFECTS can also model complex releases by linking individual models in such a way that they describe all physical phenomena that may occur during that release. For example a liquid release will consist of a release model, connected to an evaporation model, which is then linked to a dispersion model that calculates the concentration profiles in the environment. Finally it might be linked to an explosion model to calculate the ultimate effects due to peak overpressure's or heat radiation if the chemical is flammable and ignites. Furthermore it is equipped with an internal GIS system that enables the user to present the calculation results of effect and consequence calculations on a map background