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Noise Monitoring, Mapping, and Modelling Studies – A Review

Alam Pervez, Ahmad Kafeel, Afsar Shakil S., Akhtar Nasim

Journal of Ecological Engineering

2020

Vol. 21, nr 4

82--93

This paper reviews the literature on noise monitoring, noise mapping and noise modeling studies carried out in different countries by many researchers. The article reveals the current status of the noise-related studies and noise mapping studies. It was discovered that 90% of the noise monitoring studies were focused on the traffic noise, while the remaining 10% focused on the residential, commercial and industrial areas. Sometimes, there may be a necessity to analyze the sound pressure levels all over the place, or around a particular piece of land and machinery of industry. Researchers have used the noise monitoring data for the development of 2D and 3D noise maps which gives a clear picture of the noise level around the source of noise in X, Y, and Z direction. For taking a decision regarding the noise level for any development project, predicting the noise level is always necessary. The traffic noise models are generally used for the purpose of prediction. Early models are based on constant vehicle speed, later some models predicted the noise level for interrupting the traffic flow. For instance, the Stop and Go model can be used for the prediction of the noise level in an interrupted flow. Four such models were reviewed and compared in this article.

Assessment of Heterogeneous Road Traffic Noise in Nagpur

Lokhande S. K., Pathak S. S., Kokate P. A., Dhawale S. A., Bodhe G. L.

Archives of Acoustics

2018

Vol. 43, No. 1

113--121

The objective of the study is to assess the noise scenario and evaluate prediction model for heterogeneous traffic conditions. In the past few years, road traffic of Nagpur has increased significantly due to the rapid increase in the number of vehicles. Noise levels are monitored at six different squares, characterized as interrupted traffic flow due to traffic signals, high population density and heavy traffic where the major sources of noise are engines, exhausts, tires interacting with the road, horns, sound of gear boxes, breaks, etc. The A-weighted time-average sound levels (LAeq, T) are measured at the different time of day during peak and off-peak traffic hours. To assess the traffic noise more precisely, the noise descriptors such as L10, L50, L90, LAeq, T, TNI (Traffic Noise Index), NPL (Noise Pollution Level) and NC (Noise Climate) are used. In the present study, the Federal Highway Administration (FHWA) noise prediction model is used for prediction of noise levels and it is observed that one-hour duration measured LAeq, T ranged from 71 to 76 dB(A) and 71.6 to 76.3 dB(A) during peak and off peak hours respectively. Due to the heavy traffic the peak hour Sound Exposure Levels (LAE) at all locations are exceeding permissible limit of 70 dB(A) prescribed by the World Health Organization (W.H.O). Off-peak traffic hour noise levels are within permissible limit except at two locations, Jagnade and HB town square. Significant correlation was obtained when best fit lines generated between measured and predicted values gives R2 of 0.455 for all time intervals. Chi-Square test (X2) was also computed to investigate the noise levels at different squares. The results show that the inhabitants of Nagpur city are exposed to high transportation noise during daytime.