Lnight noise level of the main railway axes in Wallonia - 2017 report

This data layer locates the noise exposure from the main railway axes (more than 30000 train passages per year) outside agglomerations according to the Lnight index and integrated into the 2017 European report. The Lnight index is one of the two indicators recommended by the European Directive 2002/49/EC, relating to the assessment and management of environmental noise, in order to measure the noise level describing environmental noise. Within the meaning of the Directive, the latter is emitted by means of transport, road, rail or air traffic or comes from sites of industrial activity. The Lnight (or Ln – Level Night) index represents the average noise level determined over all night periods (from 11 p.m. to 7 a.m.) in a year. This index is, by definition, an exclusive noise index for the night period. It is associated with sleep disturbances. Unlike the parameters included in the calculation of the other indicator (Lden), no weighting is applied for its calculation. It is expressed in decibel A (dB(A)), which is the unit chosen to represent the sensitivities of the human ear. The lower noise level limit to be reported for the Lnight index is 50 dB. According to the criteria defined for the mapping of noise emanating from the main railway axes, the data layer covers only those sections of railway lines for which rail traffic is 30,000 or more train crossings per year. The data layer is a vector layer with, as an attribute, the value Lnight. 6 exposure classes are mapped: less than 50, 50-54, 55-59, 60-64, 65-69 and > 70 dB(A). The low and high values of the exposure class concerned shall be recalled as an attribute. The value class below 50 decibels is not represented at the visualization service level. The indicator is averaged over a calendar year. The data layer is therefore representative of a regional annual situation. The noise maps of the main railway axes were drawn up on the basis of source data dating from 2014 (SNCB transport plan - December 2014) or collected in early 2015. Therefore, the data layers transcribe noise exposure to this period of time. The information was reported to the European Environment Agency in 2017 and therefore included in the 2017 report.