What is Environmental Noise

Environmental noise is defined as ‘unwanted or harmful outdoor sound’ arising from all areas of human activity. Although noise is a product of many human activities - including neighbourhood noise, industrial/commercial activities, and entertainment noise - the most widespread sources of noise pollution and exposure in Ireland are from various forms of transport.

What is the EPA’s role in relation to noise?

In relation to industry, the EPA is responsible for issuing Waste, IE, and IPC licences. As part of the licensing systems, certain scheduled activities and operations have conditions attached to their licences which effect control over emissions of noise. Noise control measures and limits are generally stipulated by specific licensing conditions. Limits may be imposed at boundary positions and/or at noise sensitive locations. In addition, certain limits may be applied to specific sources of noise on-site. Typically licence conditions also place restrictions on tonal and impulsive characteristics associated with noise emissions from licensed facilities.

Environmental noise from major infrastructure including roads, railways and airports is governed by the EU's Environmental Noise Directive.

The Environmental Noise Directive (END) 2002/49/EC requires Member States to prepare and publish, every 5 years, strategic noise maps and noise management action plans for transport noise sources (i.e. roads, railways and airports) and industry.

The European Communities (Environmental Noise) Regulations 2018, S.I. No. 549 of 2018, and its amendment S.I. No. 663/2021 - European Communities (Environmental Noise) (Amendment) Regulations 2021 (irishstatutebook.ie) implements the Environmental Noise Directive.

The EPA is the national authority for overseeing the implementation of the Environmental Noise Regulations.


What is a strategic noise map?

A strategic noise map is a graphical representation of the predicted situation with regards to noise in a particular area and from particular noise sources, with different colours representing different noise levels in decibels [dB(A)]. The strategic noise maps are generated using noise modelling, which are the product of assimilating a collection of digital datasets. Strategic noise maps have been prepared for Round 4 (2022), representing the annual average situation during 2021. 

Example of section from Dublin Agglomeration Roads Noise map

Example of section from Dublin Agglomeration Roads Noise map

A strategic noise map is designed to display noise exposure levels in a given area, resulting from particular noise sources for:

  • Major roads (>3 million vehicle movements per year)
  • Major rail (>30,000 rail passages per year)
  • Major airports (>50,000 air movements per year)
  • Major cities (i.e. agglomerations >100,000 inhabitants), which includes Dublin, Cork and Limerick.

Responsibility for the preparation of the strategic noise maps rests with the designated noise mapping bodies (see table below).

What is noise measured in?

The human ear hears sound pressures over a wide range of frequencies. Decibels (dB), correspond to the way our ears interpret sound pressures. The dB value represents the annual average Lden indicator value in decibels over 24 hours. 

Where can I get this data?

You can view this data on EPA Maps. In the top menu, select Map, go to 'Environment and Wellbeing' and select 'Noise'.

  • 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. The EU's Environmental Noise Directive defines an Lden threshold of 55 dB for reporting on the numbers of people exposed.

These indicators are based on year-long averages of day, evening and night-time periods:

  • Day (7am-7pm)
  • Evening (7pm-11pm)
  • Night (11pm-7am)

What is the purpose of noise maps?

The main focus of noise maps is for the strategic management of environmental noise, based upon a notional annual average day. The maps can be used to assess noise exposure in a given area. They should not be seen as representing what may be measured directly at any location within the map, and they should not be relied upon in the context of planning applications for noise sensitive developments in the vicinity of the mapped sources. 

Noise maps are prepared every 5 years. The Round 4 Strategic Noise Maps are available on EPA Maps under 'Environment and Wellbeing' and 'Noise' and noise action plans are due to be published in January 2025. 

Data from the mapping is reported to the European Environment Agency (EEA) with information available at Noise (europa.eu). The Environmental Noise Directive defines an Lden threshold of 55 dB for reporting to the EEA on the numbers of people exposed to this minimum noise level. For Lnight the threshold of 50 dB is defined for reporting on the numbers of people exposed to this minimum noise level.

Who is responsible for strategic noise mapping?

The responsibility for noise mapping lies with the designated noise mapping bodies:

Organisation Responsible for
Local Authorities (LA) Non-national roads
Transport Infrastructure Ireland National roads and the Luas
Irish Rail Heavy rail
Dublin Airport Authority (DAA)

DAA is responsible for the Dublin airport noise map.

The airport noise map is then joined to the four LA noise maps for Fingal CC, South Dublin CC, Dublin CC and Dun Laoghaire CC, to produce one overall noise map for the Dublin agglomeration.

Agglomeration Cork

Cork City Council and Cork County Council

Agglomeration Dublin 

Dublin City Council, Dun Laoghaire/Rathdown County Council, Fingal County Council and South Dublin County Council

Agglomeration Limerick

Limerick City and County Council and Clare County Council


What is a Noise Action Plan?

Following the preparation of noise maps, the relevant action planning authorities (i.e. the relevant local authorities), are required to consult with the public in preparing noise action plans. Noise action plans are required to be made or revised every 5 years. The strategic noise maps are to be used to identify priorities (Important Areas and Priority Important Areas) for these plans. 

Under the European Communities (Environmental Noise) Regulations 2018, local authorities must report progress on their noise action plans to the EPA each year. Each local authority is required to set out the steps that have been taken to prevent, protect against and reduce excessive transport noise, as identified in the noise action plan. 

Round 3 Noise Action Plans

By way of example, links to two Round 3 Noise Action Plans are set out in the table below. Plans for these and other areas will be available on the relevant local authorities' websites.

Agglomerations Round 3 Noise Action Plan 
Cork Agglomeration  Noise Action Plan 2018-2023-Cork City Council
Dublin Agglomeration  Noise Action Plan for the Agglomeration of Dublin / Dublin City Council

Round 4 Noise Action Plans are due to be published in January 2025.