Noise zones (Type A map, LN index) of the A57, national road network granted

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.