A review and comparative analysis of European priority indices for noise action plans.

The European Union has provided in recent years (and is going to update) several tools to harmonise noise mapping methodologies through directives and guidelines. Unfortunately the same efforts have not been put in the harmonisation of approaches for Noise Action Plans, the effective instruments to manage noise impacts. As a consequence, each European Member State at national or even at local level defined its own methodology, usually considerably different one from the others. Nevertheless, the most common approach to deal with noise impact at a policy, economic and strategy level is the use of priority indices focused to highlight areas or buildings where mitigation actions are more advisable or urgent. The aim of the present research is to provide a review of the most used European priority indices and also to test some of them in a study area. The comparative analysis demonstrates that the method chosen for the prioritisation deeply affects the ranking of the areas where noise measures need to be realized. Some methods tend to give high priority to noise sensitive locations, others to high populated buildings, and others to the areas where noise levels are high. The study proves how much common approaches are needed also for Noise Action Plans to reach a coherent noise policy within European boundaries.