Dataset Direct Download Service (WFS): Noise zones related to major road infrastructure — Map of type a — Lden index (equivalent noise level over 24h) — departure from Tarn-et-Garonne

Aggregation of generic tables describing strategic noise maps pursuant to Article 3-II-1°-b of the Decree of 24 March 2006, for an infrastructure, type of infrastructure concerned: road map type a and Lden index. Noise level zones describe a noise exposure situation based on a noise indicator or area affected by noise. They are used primarily for the preparation of strategic noise maps pursuant to Article R.572-5 of the Environmental Code. Noise exposure maps (or type a map) represent the isophone curves of 5 in 5 dB(A). The maps of the areas affected by noise (or “type b” maps) are defined by prefectural decrees. And limit value exceedance maps (type c map) represent for the mapping year the areas where the Lden and Ln limit values are exceeded (the Lden index (equivalent 24h sound level) and the Ln index (noise level over a night period from 22h to 6h)). Data source by infrastructure: CEREMA, ASF本数据集为依据2006年3月24日法令第3-II-1°-b条编制的通用表格汇总，用于表征特定基础设施的战略噪声地图，所涉基础设施类型为a类道路，关联指标为Lden指数（Lden index）。 噪声等级区域以噪声指标或受噪声影响范围为依据，表征噪声暴露状况，其主要用途为依据《环境法典》第R.572-5条编制战略噪声地图。 噪声暴露地图（或称a类地图）展示以5 dB(A)为间隔的等声级曲线；受噪声影响区域地图（或称b类地图）由地方省政令划定；限值超标地图（c类地图）则展示制图年度内Lden指数与Ln指数（Ln index）超出限值的区域，其中Lden指数为等效24小时声级，Ln指数为22时至6时夜间时段的噪声级。基础设施相关数据来源：CEREMA、ASF。