Noise zones (Type A map, LD index) of the A8, licensed national road network

European Directive 2002/49/EC of 25 June 2002 on the assessment and management of environmental noise entails for EU Member States an assessment of environmental noise in the vicinity of major transport infrastructure (land and air) and in large agglomerations. This assessment is carried out in particular through the development of ‘so-called’ noise maps, the first series of which were drawn up in 2007 (1st deadline of the Directive) and 2012 (2nd deadline). Article L572-5 of the Environmental Code states that these maps are “reviewed, and if necessary revised, at least every five years”. Thus, the implementation of this review leads, in 2017 and as appropriate, to revise or renew the maps previously developed. Strategic Noise Maps (CBS) are designed to allow for the overall assessment of exposure to noise and to forecast its evolution. CBS are required in particular for road infrastructure with annual traffic of more than 3 million vehicles per year. For major road and rail transport infrastructure, the CBS are established, decided and approved under the authority of the prefect of the department. Noise maps are developed according to the indicators established by the European Directive, namely Lden (Day Evening Night Level) and Ln (Night Level). • Day/day: [6h-18h] • Evening/evening: [18h-22h] • Night/night: [22h-6h] The Lden and Ln indicators correspond to a defined energy average over the periods (Day/Black/Night) for Lden and (Night) for Ln. The corresponding results are expressed in A or dB(A) weighted decibels. Areas exposed to noise (type A map): These are two cards representing • areas exposed to more than 55 dB(A) in Lden • areas exposed to more than 50 dB(A) in Ln They are presented in the form of isophone curves materialising areas of the same sound level and are plotted by step of 5 dB(A) from the threshold of 55 dB(A) in Lden and 50 dB(A) in Ln.《2002年6月25日欧盟关于环境噪声评估与管理的第2002/49/EC号指令》要求欧盟成员国对大型交通基础设施（陆路与航空）周边及大型聚居区域的环境噪声开展评估。 该评估主要通过编制“所谓的”噪声地图实施，首批噪声地图已于2007年（指令首个截止期限）和2012年（第二个截止期限）完成编制。 《环境法典》第L572-5条规定，此类地图“至少每五年需进行复核，必要时予以修订”。 因此，该复核工作于2017年启动，并视情况对此前编制的噪声地图进行修订或更新。 战略噪声地图（Strategic Noise Maps, CBS）旨在实现噪声暴露的整体评估，并对其变化趋势进行预测。 战略噪声地图的适用范围尤其包括年车流量超过300万辆的道路基础设施。对于大型公路与铁路交通基础设施，战略噪声地图需由所在省省长负责编制、审定与批准。 噪声地图需依据欧盟指令规定的指标进行编制，即Lden（昼间-傍晚-夜间等效声级，Day Evening Night Level）与Ln（夜间等效声级，Night Level）： • 昼间时段：[6时至18时] • 傍晚时段：[18时至22时] • 夜间时段：[22时至次日6时] Lden与Ln指标分别对应昼间、傍晚、夜间时段（Lden）以及夜间时段（Ln）的加权能量平均值，最终结果以A计权分贝（dB(A)）或分贝(A)表示。 噪声暴露区域（A型地图）： 此类地图包含两类区域： • Lden值超过55 dB(A)的区域 • Ln值超过50 dB(A)的区域 此类地图以等声级线形式呈现，用于标示相同声级的区域，其绘制步长为5 dB(A)，阈值分别为Lden的55 dB(A)与Ln的50 dB(A)。