Lnight 2011 Contours

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Night time (Ln) Sound Levels in Dublin from Traffic

For those who do not wish to download Google Earth to their computer to view our noise maps on our main page, this page provides an alternative plug-in which allows our sound contour files to be viewed. It is best viewed at maximum view and then ‘zooming out’ to the location you wish.

The Sound contours displayed on this page are the Ln (Night time sound levels). The Ln value is comprised of the average of the calculated sound values for the night period (11pm -7am). Sound levels that are below those that are required to be reported to the European Commission are represented by absence of colour. So there are no Ln contours representing values below 45dB (A). The Noise Action Plan for Dublin states that night time levels above 55 decibels are undesirable and Sound levels below 50decibels are desirable.

The sound contours are not based on measurements but rather on computer modelling as required by EC Directive 2002/49/EC relating to the Assessment and Management of Environmental Noise.See here for more detail. In summary this directive requires Member States to determine (a) exposure to environmental noise, through noise mapping, by methods of assessment common to the Member States; (b) ensuring that information on environmental noise and its effects is made available to the public; (c) adoption of action plans.

Full explanation and details on the sound contours and population exposure can be found here.