Landscape image of the Limerick skyline with Clean Air Together logo

Latest Update (July 2024)

Now that Clean Air Together (Galway City) is completed, we’re putting plans in place for our next campaign - Clean Air Together (Limerick City) with a launch on Wednesday August 21st, 2024.

So, watch this space for further information in due course!

What is Clean Air Together?

Clean Air Together (CAT) is a citizen science project where people voluntarily sign up to measure levels of Nitrogen Dioxide (NO2) pollution in their local area. NO2 is predominantly a traffic-related air pollutant that can cause negative health impacts. NO2 particularly impacts children, people with pre-existing heart and lung conditions such as asthma, outdoor workers, the elderly, and those communities who may be more exposed to air pollution because of where they live or work.

The first Clean Air Together campaign took place in October-November 2021 where approximately 1,000 citizens across Dublin successfully measured NO2 near their home, business, or school. The second Clean Air Together campaign took place in October 2022 in Cork City with over 700 participants measuring NO2 at their chosen locations and now – the third phase took place in October-November 2023 with over 300 participants in Galway City.

Clean Air Together is led by the Environmental Protection Agency (EPA), in partnership with the Environmental Education Unit of An Taisce and the local authority in the area – in this case, Galway City Council for Clean Air Together (Galway City).

The project aims to create a better understanding of NO2 air pollution in Dublin, Cork City and Galway City. The citizen measurements will help the EPA develop air pollutant mapping and forecasting models for the whole of Ireland in the Life Emerald Project. Citizen measurements help in the development and maintenance of the EPA's air quality modelling and forecasting work developed through the LIFE Emerald project. Ireland's Air Quality Forecast was launched on in November 2023 and other air quality mapping products will be available in 2024. The air quality maps and forecasts will be used to inform policies aimed at improving air quality and lowering levels of NO2.

In total, over 3,500 residents have applied to participate in the Clean Air Together projects to date. This huge level of public interest and the volume of results points to a public willingness to participate in citizen science and illustrates the success of the initiative. The EPA therefore extends a massive THANK YOU to all who participated, supported, and gathered important data on NO2 pollution in Dublin, Cork City and Galway City by measuring NO2 levels outside their property. The work could not have been done without you.


What are the Clean Air Together (Galway City) Results?

The map above shows the NO2 measurements gathered by Clean Air Together (Galway City) for approximately four weeks during October/November 2023. You can click on a dot to see the level of NO2 measured at a location of interest.


What do the results mean?

A pie chart displaying the results for each risk category

The pie chart above shows the distribution of Clean Air Together (Galway City) results.

Nitrogen Dioxide levels across Galway City were generally low, with 71% of study results falling in the lowest NO2 category (0-10 µg/m3).

Higher levels of nitrogen dioxide were found along busy roads and in the city centre, which can be expected as NO2 comes mainly from traffic:

  • Dock Road
  • Merchants Road
  • Eglinton Street
  • Mary Street
  • Along Eyre Square and Briarhill/N6


A linked study by Galway City Council and the EPA, completed in conjunction with the Clean Air Together Galway City campaign, identified one area of the city which had high levels of NO2 (greater than 40 μg/m3).  A month-long measurement completed on Dock Road was indicative of a high level of NO2. This finding has now prompted a larger and longer study of traffic related air pollution along Dock Road by Galway City Council in partnership with the EPA. NO2 levels can vary considerably over the year, with changing traffic volumes and weather conditions, and this follow-on study will help to better estimate the longer-term average NO2 levels in the area. Sampling commenced in February 2024 and will run for a year.

The results clearly show the impact of traffic on NO2 air pollution levels: the more traffic there is, the higher the levels of NO2.  

Moving outwards to the suburbs and away from major roads, the measurements drop to lower levels of NO2 (light blue). Finally, most of the lowest results (dark blue dots) can be found on the outer suburbs of Galway City. 

The results also suggest that the greater the distance between a dwelling and a busy road the lower the NO2 levels. NO2 quickly reduces with distance, for example a long front garden or living on an upper floor of an apartment building can offer some protection against NO2 pollution. This finding is important as Galway City continues to grow and change. 




The Clean Air Together Results are an indication of the level of NO2 measured over a 4 week period in October/November 2023. 

NO2 levels vary over the year with changing traffic volumes and weather conditions. Therefore, it is best to view the results as a "snapshot", representative of the NO2  during the measurement period. For this reason, the result cannot be compared directly with the EU Air Quality Directive's NO2 annual average limit of 40µg/m3 or the recently updated World Health Organisation's recommendation that NO2 levels do not exceed an average of 10µg/m3 annually. 

However, you can keep the recommended values in these guidelines in mind as indicators as to where the results in your area lie. 



Scroll down to read more examples of what is being done and what you can do!


Where does NO2 come from?

Nitrogen dioxide (NO2) is an air pollutant that mainly comes from vehicle traffic. NO2 levels change throughout the year because of:

  • Traffic: As NO2 is a traffic-related pollutant, the emissions are higher around busy roads than quiet country roads.
  • Weather: Weather can significantly influence how much NO2 is in the air we breathe. In windy weather, pollution can move around whereas on very still, warm days pollution can hover, and may be higher.
  • Ventilation: The size of your surrounding streets can affect how much air pollution there is in your area. A narrow street with tall buildings can be more polluted than a wide street with lower buildings as there is less space for air to move around.

Why does NO2 matter for your health and the environment?

An image of the Galway skyline with traffic on the road and NO2 displayed in clouds above with Clean Air Together and Galway City Council Logos included

Being exposed to NO2, even for short periods, can have harmful effects on our health and wellbeing. Short-term exposure to NO2 is linked to adverse respiratory effects including airway inflammation in healthy people and increased respiratory symptoms in asthmatics. Long-term exposure is associated with increased risk of respiratory infection in children. Research from Trinity College Dublin shows that over 50’s living in Ireland in areas with higher levels of NO2 are more likely to have asthma  

NO2 pollution also impacts the environment. It affects the quality of fresh water, soil, and ecosystems, and NO2 can be absorbed to the atmosphere and later fall as something called ‘acid rain’ that can damage plant life and buildings. NO2 also behaves like a greenhouse gas.

EPA monitoring and computer modelling shows that in some urban areas NO2 pollution is increasing. The EPA in collaboration with the Local Authorities manages a national network of air monitoring stations. The EPA has 115 monitoring sites throughout the country, 3 of which are in Galway city. Real-time air quality data can be found on

While NO2 is one of the main ambient air pollutants of concern in Ireland, there are other air pollutants of high concern such as Particulate Matter (PM). To learn more about how other air pollutants can impact your health and the environment, and what is being done to lower their levels go to


What is being done and what can be done to reduce NO2?

There are many ongoing initiatives in place that aim to reduce levels of NO2 in Galway City and Ireland - and there are actions you can take to help too!

What is being done by the Local Authorities and the government?

Galway City Council recently adopted their Climate Action Plan (LACAP) 2024-2029 while at a national level the Clean Air Strategy for Ireland (2023), the Climate Action Plan (2021), and the National Investment Framework for Transport in Ireland (2021) have been adopted which all comprise of actions that will help reduce levels of NO2 across the country. These actions include among many:

  • Building more and safer cycle lanes and footpaths.
  • Investing in clean public transport and exploring the development of low emission zones. There are now multiple hybrid buses running in many towns / cities.
  • Planning to apply the 15-minute city development concept more frequently. A 15-minute city is a neighbourhood in which you can access your day-to-day needs within a 15-minute walk of your home (think schools, access to health professionals, groceries, etc.).
  • Building more electric-vehicle (EV) charging stations and making it more accessible to purchase an EV as your next vehicle purchase.

What is being done by Galway City Council to reduce NO2:

At a Galway City Council level – there are a number of strategies and plans, including the recently adopted Local Authority Climate Action Plan (LACAP) 2024-2029. The LACAP includes a comprehensive range of measures to mitigate against and adapt to climate change – for example, the pilot Decarbonisation Zone in Westside as part of the European Net Zero Cities project, or the Creative Ireland / Creative Climate Action Fund ‘Air We Share’ project linking citizen science and creativity in relation to air quality.

Galway City Council’s fleet and buildings are also being addressed as part of the LACAP - Galway City Council is in the top three local authorities for electrifying their fleet with 22% of the fleet already electrified. Galway City Council will become the first Local Authority in the country to eliminate road diesel in its larger fleet, by transitioning to Hydrotreated Vegetable Oil (HVO) as a renewable fuel source.

At a city level, implementation of the Galway Transport Strategy (GTS) will have potentially very significant positive impacts on air quality. Increasing active travel and public transport are core to the GTS – the multimodal Martin Junction Upgrade, and recently opened Salmon Weir Pedestrian and Cycle Bridge are good examples of the GTS on the ground.

Nature-based solutions will also play a key role in addressing environmental problems in our city – for example, the Grattan Beach sand fencing pilot or Buaile Bó Ballyloughane – both biodiversity projects showing the importance of innovation and partnership for positive environmental change.


What can YOU do?

An image of a cyclist passing a billboard displaying the Clean Air Together results

There are many simple steps you can take. Collectively, these steps can have a big impact on reducing the levels of NO2 across Galway City.

YOU can:

  • Think twice before using your car. One less journey a day or week can make a big difference!
  • Try to walk or cycle on shorter trips instead of using your car. This emits zero emissions and is a step towards a healthier lifestyle. Enquire with your company about the Bike to Work Scheme, safe and secure cycle parking and changing facilities at work.
  • Use public transport if it is an option for you instead of driving for longer journeys.
  • Support flexible working arrangements such as home working to reduce the number of vehicles on the road
  • Raise any concerns with your local public representative and get their support for cleaner air and healthier communities
  • Could you consider an electric vehicle for your next purchase?
  • Consider buying more local goods. Many items have travelled long distances to get to the supermarkets and each journey your purchased goods have made raises the amount of air pollution for other citizens and animal life on the planet.




Tell others about what you have learned, and the changes you are making to improve the quality of air we breathe. You can do this in many ways including through word of mouth, or through social and traditional media


Never doubt that a small group of thoughtful, committed citizens can change the world; indeed, it's the only thing that ever has
Margaret Mead (Anthropologist).