The problem of risk in urban systems is becoming increasingly important. Inside the risk, the exposure component allows significant risk reductions to be achieved. Evacuation is the most important action to reduce exposure. The paper analyzes the risk cycle starting from the main elements: transport system models; training and exercises; emerging information and communication technologies (ICT). The method followed is to identify the main variables of risk reduction, the time deltas (i.e., time between event occurence and effect), expressed for the different scenarios: reality, planning, training and exercises. With these expressions, an advanced risk cycle model is formalized, which considers time deltas as the main reference. The formalization of a dynamic model with the use of emerging ICTs is then proposed. The theoretical result is important because it allows planners to highlight the role of ICT in reducing evacuation times, both in planning and in exposure and training, and therefore in the reality of the occurrence of an event, introducing ICTs in the day-to-day modelling processes. The interpretation of formal results is important because it allows public decision-makers, technicians and planners, as well as researchers to place all models and operational results in a dynamic process.