ABSTRACT
This chapter discusses basic steps and principles for assessing and expressing the risk of major accidents in the context of Integrated Operations. Risk management is the process of identifying hazards and threats; deriving corresponding undesired events; assessing the risk; identifying and evaluating measures to reduce risk; and taking decisions. To assess risk and to use the result as a basis for decision support it is important to have a precise interpretation. Risk modelling begins by structuring accident scenarios related to the undesired events that form the focus of the investigation. The primary risk model is largely composed of logical structures such as fault and event trees. A risk analysis seldom starts from scratch. Usually, existing risk analyses form the starting point. The structuring phase of the complexity analysis is primarily a qualitative analysis where knowledge and understanding are mapped into the qualitative part of the risk analysis model.
