SOURCE RECEIVERS DISTANCE ALGORITHMS AND SOUNDSCAPES BASED METHODS FOR HOTSPOT AND QUIET AREAS IN THE STRATEGIC ACTION PLAN OF FLORENCE

Supported by their experience as noise actions planners, the authors are convinced that hotspots and quiet areas detection and delimitation, as well as definition of noise reduction actions, shouldn’t be based only on noise measurements and consequent mapping.
In Florence Action Plan, hotspots detection has been performed applying algorithms based on source-receiver distance to the urban platform representing the whole territory of the agglomeration. The extension of the areas where to protect or improve the acoustic atmosphere has been found employing calculation methods based on source-receivers relative distance. In particular, for linear sources, the S-R distance is increased by a factor leading to determinate the portion of source to be considered in a specific action. On the other side, the idea of developing soundscape based methods for quiet areas is inspired by the growing interest and improved knowledge in the field of soundscapes analysis as well as by the need of producing plans that can be referred to people’s perception of sounds and noise in the urban areas, identified as quiet ones.
In the proposed methods, a single area or sub-area is investigated applying to it a procedure that identify, recognise, characterise and localise the different types of sound, contributing to the multisource mixed sound environment. Not only measurements of the overall effects of noise, in terms of sound level and frequency are considered, but also levels of perceived annoyance are considered. Some significant soundscapes of quiet scenarios, extracted by the freshly finalized Florence action plan, are described.

Authors: Bellomini, Luzzi