Areas exposed to noise from the departmental road 850 west of Niort at night (Ln) in Deux-Sèvres

The European Directive on Strategic Noise Maps requires at least the representation of global noise indicators Lden and Ln, for each source. These indicators correspond to the incident noise on the facades. The indicators represented are expressed in dB(A) and reflect a notion of overall discomfort or health risk. The data represents areas exposed to noise from land transport infrastructure at night (Ln) at l' using isophone curves plotted by 5 dB(A) steps from 50 dB(A). The roads concerned are Boulevard Louis Tardy, Boulevard Jean Moulin, l' avenue Salvador Allende, l'Avenue de Welling Borought and Henri Sellier Street in Niort. The Ln is the average sound level that isolates the night period (22h-6h). It may be associated with the risk of sleep disturbances. Articles L572-1 to 11 of the Code de l' Environment laying down various provisions of; adaptation to Community law in the field of the Environment and the texts of #x27; Applications (Decree No 2006-361 of 24 March 2006, Decree of 4 April 2006 and Circular of 7 June 2007 on the issue of noise maps and noise prevention plans in the field of environment) provide for the indicators, methods of calculation to be used and results I'm waiting. __Origin__ The geometric modeling of ' entity at ' origin of risk depends on the type of risk, the context of the PPR, the nature of the generator and its modeling in the data source or geographical repository from which it originates. For example, a water course may be represented by a polygon or a polyline according to its size and width, an ICPE by a point (if the location of its enclosure is not known) or by a polygon (especially from the grey area of the PPR).The geometry of this class d' objects is optional when: — this geometry is already carried by an object d'a geographical repository or d' an external data source, to which it is then recommended to refer to the ' help of its identifier (and thus avoid unnecessary duplication);- it does not exist because the origin of the risk cannot be precisely defined or localised (c' is the case of certain risks such as, for example, earthquakes, avalanches, sea submersions...)Nevertheless, as it is in practice rare to benefit from stable references to external objects, the geometry of l' origin of the risk will often result from the duplication of that of the #x27; object representing the #x27; origin of the risk. __Partner organisations__ DDT Deux-Sèvres __Links annexes__ * [XML metadata view](http://ogc.geo-ide.developpement-durable.gouv.fr/csw/all-dataset?REQUEST=GetRecordById&SERVICE=CSW&VERSION=2.0.2&RESULTTYPE=results&elementSetName=full&TYPENAMES=gmd:MD_Metadata&OUTPUTSCHEMA=http://www.isotc211.org/2005/gmd&ID=fr-120066022-jdd-a0fbb726-c6ea-4528-beed-4513c422fddb) * [COVADIS data standard: Surface Entity at #x27; Origin of Risk of PPRN](http://geostandards.developpement-durable.gouv.fr/afficherPageStandard.do?jeu=N_ORIG_RISQ_PPRN_AAAANNNN_S) [See this page on geo.data.gouv.fr](https://geo.data.gouv.fr/fr/datasets/3044d8333c7b3654ae871e8f2599be6bce2a44bb)