During three workshops, experts were presented with the event tree analysis, and asked to give feedback on the approach. Three workshops were arranged in the IRTORISKI-project during
2010. In addition to judging the content of the ETA, the experts were asked to evaluate the usability of the whole ETA process in relation to flood risk assessment. The experts represented the areas of building/real estate, water works, electricity and infor- mation networks and land use planning