Georeferenced Spectral Maps an Improved Instrument for Action Planning on Environmental Noise Mitigation

Abstract

Exposure-response relationships have been widely studied using A weighted equivalent sound pressure level (Leq,A) measured outside building environments in contrast with field surveys. On one hand low frequencies are minimized by A-weighted filter network. On the other hand low frequencies are predominant even inside buildings for some of the most salient sources in many cities (i.e. road traffic). These relationships do not consider that people spend a large part of their time inside building environments. The spread of the exposure-response relationships can, presumably, be reduced by relating people response to the noise spectrum levels inside building environments instead of the outdoors Leq,A. Outdoors spectral maps can be georeferenced using geographical information systems. Then the indoors spectrum for each building can be estimated if the georeferenced data of façades and interiors properties were available. Furthermore city planners can use the outdoors spectral maps to estimate the adequate sound insulation of façades for new projects. In this article a georeferenced spectral map of a part of the city of Rosario, Argentina is developed using inexpensive resources and some interesting tools for this purpose are presented using technical computing software. Different forms of presenting the data are analyzed in relation to the requirements of different agents, public, city planners, Geographical Information Systems users, etc.