Risk assessment in avalanche-prone areas

This paper addresses the problem of defining a proper method for formal risk analysis in avalanche-prone areas. In this study, risk is defined as the annual probability of being killed by an avalanche for someone living or working permanently in a building under a hazardous hillside. A new methodology to estimate the hazard component of avalanche risk based on the use of dynamic models is introduced. This approach seems to have some advantages over the current methods based on statistical analysis of historic avalanche data. The vulnerability component of risk is formulated as a function of avalanche velocity, according to previous formulations. However, given the lack of knowledge on how avalanche impact damages structures and causes fatalities, the effect on the resulting risk mapping of using different vulnerability relations is explored. The potential of the proposed approach for evaluating the residual risk after the implementation of defensive structural work is discussed.