Resumo ObjetivoAnalisar comparativamente a percepção ao ruído urbano no cotidiano dos habitantes de uma zona controlada acusticamente e outra não controlada. Métodos Duas zonas de uma cidade foram selecionadas por meio de avaliações objetivas dos níveis sonoros equivalente como zona controlada e zona não controlada acusticamente. Uma amostra aleatória de cada zona foi selecionada e submetida a questionário. Foram gerados indicadores estatísticos da percepção ao ruído urbano por meio da análise multivariada fatorial. Resultados O valor médio para o nível sonoro (L eq ) encontrado no centro (zona não controlada acusticamente) foi de 72,9 dB(A), e na zona controlada acusticamente foi de 53,3 dB(A). A análise multivariada fatorial gerou três indicadores estatísticos: percepção temporal, percepção de ruídos atípicos e fontes e distúrbios. Conclusões A população da zona controlada indicou aumento no nível de ruído percebido. O nível sonoro no centro da cidade tem se mantido praticamente constante e muito acima do especificado pela Lei Municipal. Os indicadores gerados podem servir como parâmetros para caracterizar a percepção à exposição contínua ao ruído pela população. Abstract ObjectiveTo comparatively analyze the perception of daily urban noise between residents of an acoustically and a non-acoustically controlled area. Methods Two urban areas were selected through objective assessments of equivalent sound levels and defined as a non-acoustically and an acoustically controlled area. A random sample of each area was selected and a questionnaire was applied to its residents. Statistical indicators of urban noise perception were generated through factorial multivariate analysis. ResultsThe average sound level (L eq ) found in the downtown district (a non-acoustically controlled area) was 72.9 dB(A) and in the acoustically controlled area was 53.3

An evaluation was made of the acoustic environment generated by an urban highway using in situ measurements. Based on the data collected, a mathematical model was designed for the main sound levels (L (eq), L (10), L (50), and L (90)) as a function of the correlation between sound levels and between the equivalent sound pressure level and traffic variables. Four valid groups of mathematical models were generated to calculate daytime sound levels, which were statistically validated. It was found that the new models can be considered as accurate as other models presented in the literature to assess and predict daytime traffic noise, and that they stand out and differ from the existing models described in the literature thanks to two characteristics, namely, their linearity and the application of class intervals.

In the modern world, noise pollution continues to be a major problem that impairs people’s health, and road traffic is a primary contributor to noise emissions. This article describes an environmental impact study of the noise generated by the reconstruction of an urban section of a highway. Noise maps were calculated, and an environmental impact matrix was generated to determine the environmental impact of this reconstruction. The implementation of noise barriers was simulated based on these noise maps, and the effectiveness of the barriers was evaluated using Artificial Neural Networks (ANNs) combined with Design of Experiments (DoE). A functional variable significance analysis was then made for two parameters, namely, the coefficient of absorption of the barrier material and the barrier height. The aim was to determine the influence of these parameters on sound attenuation and on the formation of acoustic shadows. The results obtained from the ANNs and DoE were consistent in demonstrating that the absorption coefficient strongly influences the noise attenuation provided by noise barriers, while barrier height is correlated with the formation of larger areas of acoustic shadow. The environmental impact matrix also indicates that the existence of noise pollution has a negative effect on the environment, but that this impact can be reversed or minimized. The application of simulated noise barriers demonstrated that noise levels can be reduced to legally acceptable levels.

This work analyses, using a comparative approach, the environmental noise perception in the daily lives of inhabitants of a residential area, with that of a mixed (residential and commercial) area (downtown), in a large Latin America city. The goal was to confront an ideal urban environment with one acoustically polluted, as function of noise descriptors. Concomitant with the evaluation of noise perception (subjective analysis), noise levels were measured (objective analysis) in both areas. The single average equivalent noise level (Leq) found for downtown was 73 dB(A), and 53 dB(A) for the residential area. A random sample of the populations of both areas was taken, through a questionnaire. Questionnaire data was treated statistically through a factorial multivariate analysis. This analysis has generated three statistical indicators: time perception, atypical noise perception, and sources and disturbances. Over 50% of both populations sampled have the perception that high frequency noise levels are gradually increasing, with higher contribution from traffic noise. The dominant organic effects reported were irritability and loss of concentration ability, these last being precursors of hearing loss.

The purpose of this work is to analyze the urban noise perception comparatively in the inhabitants of a residential area (neighborhood) and a mixed area (center), in the city of Curitiba, PR, in order to characterize two different situations: (1) acoustically ideal urban environment; and (2) acoustically polluted urban environment. For that, subjective and objective evaluations were accomplished, where an aleatory sample of each area was submitted to a survey. In the objective evaluation, the medium equivalent sound levels calculated were 53.50 dB(A) and 72.90 dB(A) for the neighborhood and center, respectively. The parameters used for comparison of the calculated medium equivalent sound levels where the values of 55.00 dB(A) (Municipal Law No. 10.625) and 65.00 dB(A) (WHO), in the period of the day for residential areas. The interpretation of the subjective results verified that the central zone inhabitants have an annoyance perception bigger than the residential zone inhabitants. The interpretation of the objective results classified the neighborhood and center areas as acoustically control zone and acoustically polluted zone, respectively, according to the adopted parameters. Starting from the comparison between these two areas, it was defined that both can be classified as reference factor for other evaluations.