Distributed System for Noise Threat Evaluation Based on Psychoacoustic Measurements

Abstract

An innovative system designed for the continuous monitoring of acoustic climate of urban areas was presen ted in the paper. The assessment of environmental threats is perf ormed using online data, acquired through a grid of engineered monitoring stations collecting comprehensive infor mation about the acoustic climate of urban areas. The grid of proposed devices provides valuable data for the p urpose of long and short time acoustic climate analysis. Dynamic estimation of noise source parameters and r eal measurement results of emission data are utilized to create dynamic noise maps accessible to the general public . This operation is performed through the noise source prediction employing a propagation model being o ptimized for computer cluster implementation requirements. It enables the system to generate noise maps in a reasonable time and to publish regularly map u pdates in the Internet. Moreover, the functionality of the s ystem was extended with new techniques for assessing noise-induced harmful effects on the human hearing system. The principle of operation of the dosimeter is based on a modified psychoacoustic model of hear ing and on the results of research performed with participation of volunteers concerning the impact of noise on hearing. The primary function of the dosimeter is to estimate, in real time, auditory effects which are caused by exposure to noise. The results of measurements and simulations performed by the system prototype are depicte d and analyzed. Several cases of long-term and short-term measurements of noise originating from various sou rces were considered in detail. The presented outcomes of predicted degree of the hearing threshold shift i nduced during the noise exposure can increase the awareness of harmfulness of excessive sound levels.