Laboratory of Environmental and Industrial Acoustics and Acoustic Comfort, Federal University of Paraná, Brazil.
Laboratory of Environmental and Industrial Acoustics and Acoustic Comfort, Federal University of Paraná, Brazil.
Sci Total Environ. 2021 Feb 25;757:143721. doi: 10.1016/j.scitotenv.2020.143721. Epub 2020 Nov 14.
Rail freight transport has grown worldwide and in Brazil as well, which increases people's exposure to railway noise. A promising tool to manage it is Strategic Noise Mapping (SNM), which has advanced around the world favoring a common and more accurate calculation method that requires more accurate measurements. This paper presents a framework to manage railway noise exposure in Brazil based on a case study carried out in the city with the longest stretches of railway tracks in urban areas. Background noise due to road traffic and train pass-by noise levels were measured for knowledge of noise sources and SNM calibration. Background noise predicted by the CNOSSOS-EU (Road) method reached an accuracy within ±2 dB(A) and was overestimated by the NMPB-96 method. The combination with railway noise using the SRM II and ISO 9613 calculation methods maintained the aforementioned accuracy, while the current best fit CNOSSOS-EU (Railway and Industry) configuration for the study area overestimated it. Although the study area is a quiet suburb, a quarter of its population is exposed to road traffic noise levels above those recommended by WHO, and more than 40% are affected by rail noise that is 5 dB(A) or higher than the background noise. The elimination of level crossings (LC) and the need to sound the train horn is more cost-effective than noise barriers. Therefore, the strategy to manage exposure to rail noise in Brazil should involve altering residential zoning of non-built-up areas next to the railways to repurpose them for other land uses and/or establish acoustic performance criteria for new buildings; federal government investing in reducing the number of LC or railway variants; and railway operators investing in the creation of an emission database for noise control at the source.
铁路货运在全球范围内有所增长，巴西也不例外，这增加了人们接触铁路噪音的机会。一种有前途的管理工具是战略噪声图（SNM），它在全球范围内得到了发展，有利于采用更通用和更准确的计算方法，这需要更精确的测量。本文提出了一个基于巴西一个案例研究的框架，以管理铁路噪声暴露，该案例研究在城市中进行，该城市拥有最长的城市铁路轨道。由于道路交通产生的背景噪声和火车经过时的噪声水平进行了测量，以便了解噪声源和 SNM 校准。使用 CNOSSOS-EU（道路）方法预测的背景噪声达到了±2dB(A)的精度，而 NMPB-96 方法则过高估计了背景噪声。使用 SRM II 和 ISO 9613 计算方法与铁路噪声结合使用，保持了上述精度，而研究区域当前最佳的 CNOSSOS-EU（铁路和工业）配置则过高估计了背景噪声。尽管研究区域是一个安静的郊区，但四分之一的人口受到道路交通噪声水平的影响，这些噪声水平超过了世界卫生组织的建议，超过 40%的人受到铁路噪声的影响，铁路噪声比背景噪声高出 5dB(A)。消除道口（LC）和鸣笛的需求比安装声屏障更具成本效益。因此，巴西管理铁路噪声暴露的策略应包括改变铁路旁非建成区的住宅分区，将其重新用于其他土地用途和/或为新建筑建立声学性能标准；联邦政府投资减少 LC 或铁路变体的数量；以及铁路运营商投资创建用于源头噪声控制的排放数据库。
