Dose-response relationship of the noise on central streets the city of Pelotas, Brazil

Abstract

Because of the disorderly growth of cities, linked to the increase in demographic density, noise sources appear capable of generating negative environmental impact and significant damage to the population. Given the lack of studies on anthropogenic acoustic noise in the city of Pelotas / RS, the need to qualitatively and quantitatively assess the incidence of noise pollution in the central area of ​​the city became evident. Sound pressure levels were measured with an integrating sonometer, obtaining the LAeq value, at 309 different points, located at the corners of intersections in the central streets of the city. Percentage doses of daytime and nighttime sound pressure levels were calculated, with 6 dB being attributed as a dose doubling factor. Also, residents, workers, and visitors from the central region of the city were interviewed to assess their perception of noise. It was found that 98% of the measurements taken at street intersections are above the limits recommended in NBR 10.151 and that all of them exceed the municipal limit, with more than half being between 400 to 800% of the dose, reaching some points at values ​​greater than 1600% for the night period, exceeding 4x the established limit. Through the interviews, it was found that most people consider the downtown area of ​​Pelotas to be noisy, pointing out vehicle traffic as the main source of noise, which bothers 78% of respondents, the most reported symptom being irritability. Therefore, the central area of ​​Pelotas is considered acoustically polluted, denoting the lack of urban planning.