Noise Mapping

Disclaimer: It should be noted that the main focus of noise maps is for strategic management of environmental noise, based upon a notional annual average day. They should not be seen as representing what may be measured directly at any location within the map.

Update 31 January 2018:  The Round 3 Strategic noise maps are due to be completed by March 2018.  As soon as the maps have been prepared they will be published on EPA Maps.


Environmental noise means unwanted or harmful outdoor sound created by human activities, including noise emitted by means of transport, road traffic rail traffic, air traffic, and from sites of industrial activity. It is among the most frequent sources of complaint regarding environmental issues in Ireland and throughout Europe, especially in densely populated urban areas and residential areas. The 7th Environmental Action Plan (EAP) includes an objective that noise pollution in the EU has significantly decreased by 2020, moving closer to WHO recommended levels.

The Environmental Noise Directive (END), EC 2002/49/EC, was transposed into Irish Law as Statutory Instrument, S.I. 1401 of 2006, Environmental Noise Regulation 2006. The Directive requires Member States to prepare and publish, every 5 years, noise maps and noise management action plans. The aim of then END is to provide a common framework to avoid, prevent or reduce, on a prioritised basis, the harmful effects of exposure to environmental noise through the preparation of strategic noise maps and the development and implementation of action plans. 

Roles and Responsibilities

The EPA is the national authority for overseeing the implementation of the Regulations and its role includes supervisory, advisory and coordination functions in relation to both noise mapping and action planning, as well as reporting requirements for the purpose of the Directive.

Responsibility for the preparation of the relevant noise maps lies with the Noise Mapping Bodies (NMBs) which include Dublin City Council, Transport Infrastructure Ireland TII (responsible for National roads, LUAS), Local Authorities (LAs), responsible for non-national roads, Irish Rail (heavy rail), Dublin Airport Authority (daa), as well as Fingal, Dún Laoghaire-Rathdown, & South Dublin LAs. The preparation and implementation of the resulting noise action plans occurs at local level and is the responsibility of the Local Authorities.

Strategic Noise Maps

A strategic noise map is designed to assess noise exposure in a given area, resulting from particular noise sources such as roads, railways and airports. Such maps are normally prepared using computer modelling techniques. Such techniques calculate the noise level at specific points resulting from the sound emanating from the source being studied. The modelling software uses source data such as traffic flow, type of road and rail, types of vehicles and speeds.

In accordance with the requirements of the Noise Directive the EPA has made available the strategic noise mapping of major agglomeration airports, major roads and major rail networks, in the form of noise contours for the Lden (day, evening, night) and Lnight (night) periods. A noise map is a graphical representation of the predicted situation with regards to noise in a particular area with different colours representing different noise levels in decibels [dB(A)].

All noise maps are presented in terms of two noise indicators: Lden and Lnight.

  • Lden is the day-evening-night noise indicator and it represents the noise indicator for overall annoyance. It is ‘weighted’ to account for extra annoyance in the evening and night periods. The END defines an Lden threshold of 55 dB for reporting on the numbers of people exposed.
  • Lnight is the night time noise indicator and is used in the assessment of sleep disturbance. An Lnight threshold of 50 dB is defined for reporting on the numbers of people exposed.

These indicators are based on year long averages of the day (07:00-19:00), evening (19:00-23:00) and night (23:00-07:00) time periods.

Where can I get this data?

You can view the data using our WebGIS on the Map link, under the Noise group. You can download the data from the EPA Database option of the Get data page, including Metadata and style files (.lyr).

Noise Action Planning

Following the preparation of the noise maps, the relevant Action Planning Authorities (APAs) i.e., the local authorities, are required to prepare noise action plans where the Lden (55 db) and Lnight (50 dB) thresholds have been exceeded. The Directive neither sets limit values for noise exposure, nor does it prescribe measures for inclusion in the action plans.

The action plans are designed to act as a means of managing environmental noise by controlling future noise by planned measures, such as land-use planning, systems engineering for traffic, traffic planning, abatement by sound-insulation measures, and control of noise sources. The EPA has produced guidance for Local Authorities on the content of such plans.

The APAs are required to ensure that the public are given sufficient opportunities to participate in the preparation of the draft plans and that the results of such participation are taken into account in finalising the plans.

Review of noise maps

The noise Regulations require that noise mapping bodies (NMBs) review and, where necessary, revise each strategic noise map every 5 years, or when a material change in environmental noise in the area concerned triggers a revision of the relevant noise action plan. The NMBs undertook strategic noise mapping for the second round in 2012, are currently undertaking a review of the strategic noise maps. The third round of noise mapping will cover the period from 2016 – 2018.

Learn More

Live Green: See also Live Green – has a section on noise nuisance.

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