Abstract
Many engineering facilities are complex prototypes which manage huge energy quantities. Their interaction with the surroundings may impact significantly on the population, economy and the environment. Different areas of engineering and technologies take part in all the stages, from the initial conception of the project to the construction and further on.
In the other hand the concept of risk is widely treated in the bibliography. This concept includes both undesirable consequences and likelihoods. A very common definition of risk represents it as a set of:scenarios (set of accident scenarios), likelihoods (evaluation of the probabilities of these scenarios), and consequences (estimates their consequences) within each set are uncertainties. The uncertainties relate to whether all the significant accident scenarios have been identified, and whether the probabilities of the scenarios and associated consequence estimates have properly taken into account the sources of variability and the limitations of the available information.
Risk analysis not only is about technical factors (mostly random) but the non technical like organizational or due to the human factor. It is well known that the principal cause of failures is due to human errors. Diverse approaches have been proposed from deterministic to qualitative methods which in essence try to take into account and represent with more refinement the different types of uncertainties. Nevertheless it is accepted that risk is the union (convolution) among the probability of failure and the consequences on the surroundings.
With the aim to take into account and incorporate all these aspects in risk analysis, a holistic approach is presented in this paper. A hierarchical scheme permits incorporate random and epistemic uncertainties. Some considerations about the human factor role are made and a possible treatment is proposed. An estimation of loss of lives downstream a dam under a failure scenario is presented as an example. A map is the outcome of the analysis which can contribute in decision making within dam safety management.
