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Welsh Air Quality Forum Annual Seminar – Thursday 12 October, Caerphilly Council Chamber at Penallta House
Published Date: 14/09/2017

We are pleased to announce this years Welsh Air Quality Forum will take place on Thursday 12th October, Caerphilly Council Chamber at Penallta House. Please follow this link to see the Provisional Programme for the day and this link to the booking form.

The seminar theme this year will be NO2 plans Clean Air Zones (CAZ) zones and the way forward from a national, regional and local level. This will include an update on Welsh Government policy guidance, case studies on taking a regional approach, CAZ pilot studies, and examples of impacts of measures such as walking schools and the introduction of low emission buses.

» Conference Booking Form (pdf)
» Final Agenda (pdf)

Website Improved - Air Quality Exceedance Summary and Statistics Download
Published Date: 01/10/2012

New features have been added to this website to enable users to:

New Daily Air Quality Index implemented
Published Date: 05/01/2012

The changes announced on 16th December 2011 by Welsh Government (see previous news item) have now been implemented on this website.

Latest air quality data and bulletins will now present results according to the new DAQI which includes PM2.5 particle measurements for the first time.

Details of how the new DAQI is used is now available.

Notification of Changes to the Air Quality Index
Published Date: 16/12/2011

The Committee on the Medical Effects of Air Pollutants (COMEAP) was asked by Defra and the Devolved Administrations to review the Air Quality Index to ensure that it is fit for purpose given developments in the field of air quality. The current index has been in operation essentially unchanged for a period of around 12 years. COMEAP published the report Review of the UK Air Quality Index in June 2011. Defra and the Devolved Administrations have considered the report recommendations and will implement several changes, following consultation with index users. The implementation of the new index, to be renamed the Daily Air Quality Index (DAQI) is described in this letter. This letter is also available in Welsh.

Consultation on Draft Air Quality Plans to meet EU limit values for Nitrogen Dioxide (NO2) in Wales
Published Date: 10/06/2011

The European Union (EU) Ambient Air Quality Directive sets limits for major air pollutants. One of these is nitrogen dioxide (NO2). We have made improvements in air quality, but there are still some areas where more action and time is needed to meet these limits. We have produced draft air quality plans for these areas. They show how we intend to meet these limits by 2015.

Please read the documents and provide your views by visiting the consultation page.

Summary of PM10 episode across England and Wales during March 2011
Published Date: 19/04/2011

Between the 25th and 30th of March, the AURN experienced a widespread PM10 episode of moderate air pollution levels. This event was due to a mixture of local emissions and transboundary pollution from continental Europe. The note below investigates and briefly summarises this matter further.

» Download note (pdf)

Port Talbot Margam PM10 data May to November 2010
Published Date: 12/11/2010

The data reported through this website are provisional, and may be subject to change during the normal ratification process. However, initial quality control checks have indicated that the automatic PM10 data (hourly measurements) may be of unacceptable quality due to operational problems with the analyser. It is therefore possible that these data may be deleted altogether, from early summer up to November 2010. Despite these issues, provisional data will continue to be displayed on this website in near-real-time for public information. A course of action to rectify the analyser's performance is in hand.

The site has a co-located gravimetric PM10 sampler (also known as the Partisol), which should provide sufficient information to allow the calculation of the full set of annual statistics for PM10 at this monitoring location. However, due to the manual nature of the sampler, data are only made available three months after sampling, while the filters are collected, conditioned and weighed as per the appropriate method, and the results are ratified. The Partisol data can be downloaded from here.

More information about provisional and ratified data is available at

A report on the QA/QC process for the AURN can be downloaded here.

New Annual Report for 2009 published
Published Date: 24/09/2010, by AEA

We are pleased to announce the release of the latest annual air quality report for Wales. This year our feature article is consideration of the links between air quality and climate change, and includes practical advice on how individuals can reduce their carbon footprint.

We also provide a summary of recent air pollution events of interest, including an early look at the activities which took place during the eruption of the Eyjafjallajokull volcano in Iceland in April and May 2010.

» Download 2009 Annual Report - English (pdf)
» Download 2009 Annual Report - Welsh (pdf)

The Eyjafjallajokull Volcanic Ash Cloud and its Effects on Welsh Air Quality - Update 6th May 2010
Published Date: 06/05/2010

The volcanic ash cloud from the Eyjafjallakull volcano once again grounded flights from some UK airports between 4th and 5th May. Even though the ash cloud did not affect flights from Welsh airports it was still situated above Wales albeit at a concentration that did not pose a risk to aircraft engines.

Please see details.

The Eyjafallajokull Volcanic Dust Cloud and UK Air Quality
Published Date: 15/04/2010

Currently there is a cloud of volcanic ash situated over the UK, caused by the eruption of the Eyjafallajokull volcano in Iceland. This cloud of volcanic ash has grounded most flights from UK airports, due to the dangers to aircraft engines from the fine abrasive dust. Current 96 hour back trajectory clearly indicate that air arriving over the UK has originated from Iceland.

The air mass back trajectories agree closely with the graphics issued by the Volcanic Ash Advisory Centre, VAAC, showing the plume’s location. This shows that the ash cloud originated over Iceland and then travelled eastward towards Scandinavia, before heading South West towards the UK.

Currently the cloud of volcanic ash is estimated to be at an altitude of between 6 -11km; the likelihood of it grounding in the next 24 hours over the UK and its effect on ground level air quality is therefore expected to be minimal. Current PM10 concentrations are low as measured by AURN air monitoring stations. There is at the present time no apparent significant rise in PM10 levels due to the cloud. We will continue to monitor the situation closely and advise of any developments.

Please see details.

LAQM Review Publication
Published Date: 16/03/2010

A review published today details the findings and subsequent recommendations of the In-House Policy Consultancy (IHPC) report into Local Air Quality Management (LAQM).

The report was commissioned by Defra and the Devolved Administrations to assess the operation of local air quality management in the UK and to make recommendations with a view to:

1. Improving air quality outcomes.
2. Making better use of available LAQM resources.

A Questionnaire Survey accompanies the review. The survey, also commissioned by Defra and the Devolved Administrations, was undertaken by the University of West of England and Air Quality Consultants. 239 local authority air quality practitioners submitted responses to the questionnaire, which drew out the strengths and weakness of the current system, as well as opportunities for improving it. The results of the survey are very much in line with the conclusions reached in the IHPC review.

Defra, in conjunction with the Devolved Administrations, welcomes the review and questionnaire survey, and will be considering the recommendations.

For more information, you can download the full reports from

Air Pollution: Action in a Changing Climate
Published Date: 09/03/2010

The UK could save £24 billion through joint measures to help prevent both air pollution and climate change according to 'Air Pollution: Action in a Changing Climate' published by Defra and the Devolved Administrations today.

For more information, you can download the full report from

NEW Emission Factor Toolkit, NOx to NO2 calculator, background maps and future-year projection factors
Published Date: 12/02/2010

A number of changes have recently been made to the Local Air Quality Management tools available on the Air Quality Archive website at The new tools should be used for new work. If work has already been started using the old set of tools, it is not necessary to go back and repeat the work unless the local authority believes that this would be appropriate. So long as models have been appropriately verified against local measurements, the updates to the tools should not invalidate work already carried out, even though precise results would be different. The changes are as follows:

1) The Emission Factor Toolkit (EFT) has been updated to use the DfTs latest vehicle emission factors (published in 2009). This allows modellers to calculate vehicular emissions in line with the latest predictions. It is possible for users to incorporate the emissions that they calculate using the EFT into most dispersion models (but not screening tools such as DMRB).

2) The NOx to NO2 calculator has been updated. These changes take account of more recent predictions of oxidant levels across the UK and also use revised default values for primary NO2 (fNO2) (as shown within the spreadsheet).

3) The national maps of background air pollutant concentrations have been updated to take account of more recent emissions predictions and updated methods. A short report describing the principal changes between the two sets of maps is included on the website along with the maps.

4) The sector-removal tool for calculating sector-adjusted background nitrogen dioxide concentrations has been updated following changes to the background mapping methodology.

5) The future-year projection factors for roadside monitoring data contained in Box 2.1 of LAQM.TG(09) have been updated.

All of these tools can only be applied to data from the year 2008 onward. A FAQ on modelling conditions prior to 2008 will follow soon.

If local authorities require any help or clarification they should contact the Review and Assessment Helpdesk.

Consultation on the Air Quality Standards (Wales) Regulations 2010
Published Date: 14/01/2010

This consultation is about regulations that bring Directive 2008/50/EC on ambient air quality and cleaner air for Europe (the 'CAFE' Directive) into force.

Click here for a link to the full consultation documents.

This consultation should be read in conjunction with the Department for Environment, Food and Rural Affairs (Defra) consultation on regulations on the CAFÉ Directive in England, part of which applies to the whole of the UK.

The consultation period ends on 05/03/2010.

Independent Review of PM10 Monitoring at Port Talbot - 26th November 2009
Published Date: 26/11/2009

An Independent Review of Monitoring Measures Undertaken in Neath Port Talbot in Respect of Particulate Matter (PM10) has been published by the University of the West of England (UWE) on behalf of the Welsh Assembly Government. The report is now available on the WAG website.

New Annual Report for 2008 published on 1st October
Published Date: 30/09/2009, by AEA

We are pleased to announce the release of the latest annual air quality report for Wales, available for immediate download. This year we examine a number of interesting air pollution episodes during 2008, resulting from both long-range transport of dust and road traffic. We also undertake comprehensive investigations of the latest trends and spatial distribution of pollutants for Wales.

This year, for the first time, we review the wide-ranging activities of the Welsh Air Quality Forum; we have also compiled case studies and practical experience of WAQF members operating the latest FDMS particulate analysers.

A comprehensive range of detailed air quality analyses, statistics, data summaries and graphs is included on a CD, provided with hard copies of the report.

» Download 2008 Annual Report - English (pdf)
» Download 2008 Annual Report - Welsh (pdf)

Revised PM10 Air Quality Index for Reference Equivalent Data
Published Date: 04/08/2009

In the UK over the last two years and more, there has been a steady replacement of old TEOM PM10 monitors with reference equivalent instruments. This has happened both in the national monitoring networks for European Directive compliance, and at the regional and local level for local air quality management purposes.

The current PM10 air quality index for reporting real-time public information from TEOM monitors is not directly transferable to other reference equivalent monitors and therefore requires updating. The results of the PM10 equivalence programme (carried out between November 2004 and January 2006) have been analysed to develop an equation relating old TEOM data to reference equivalent monitors as follows:

Reference equivalent PM10 = TEOM x 1.3 - 2.2494

On this basis the Committee on the Medical Effects of Air Pollutants (COMEAP) have agreed the air quality index for PM10 and breakpoints for “Low”, “Moderate”, “High” or “Very High” pollution can be assigned to old TEOMs or reference equivalent data. For further details of the background to this and proposed changes please see the attached short paper here.

Final UK Sustainable Development Air Quality indicator 2008
Published Date: 16/07/2009

2008 was a largely unremarkable year for air pollution. Downwards trends in PM10 particulate concentrations continued at both urban background and roadside locations, whilst urban ozone levels continued the steady increase seen in previous years. Further detailed information can be found here:

There is very little change from the provisional figures published in January 2009.

The openair project
Published Date: 20/05/2009

The Institute for Transport Studies at the University of Leeds is pleased to announce the launch of the openair project. The 3-year openair project is funded by the Natural Environment Research Council (NERC) with additional funding from Defra, AEA and several local authorities.

The project aims to make innovative, open-source data analysis tools available for free to the air quality community. These tools are designed for the analysis of air pollution data and dispersion model output. The underlying theme of the project is that considerably more useful information can be gleaned from air quality data using tools specifically designed for the purpose than is usually the case. As such, the tools should have wide appeal from central and local government, consultancies, regulators and university researchers. Many of these tools would normally require specialist visualisation or statistical software but have been made available in the highly developed open-source statistical software called R.

The website at provides more details on the project and a pre-release version of the openair “package” that users can test ahead of its final release in October 2011. The project will be continuously developed over the next few years and we are keen to receive user feedback to ensure the tools are of maximum benefit to the community.

AEA and ITS are working to apply these tools to AURN data presented on the AQ Archive. This will allow web users a greater range of functionality, visualisation and analysis when interrogating the national network measurements.

Contact: David Carslaw (

The Welsh Assembly Government issues revised Technical and Policy guidance to local authorities on improving air quality
Published Date: 14/05/2009

The Welsh Assembly Government has issued revised guidance to all local authorities in Wales on managing air quality. Under Part IV of the
Environment Act 1995, all Local Authorities have a duty to manage air quality. The guidance is intended to support authorities in their
efforts to tackle poor air quality and to fulfil their statutory duties under the Act. The guidance should be taken into account by all local authority departments involved in local air quality management (LAQM), including environmental health, corporate services, planning, economic development and transport planning. The revised policy guidance document is accompanied by four new practice documents covering; assessment of air quality measures, implementing low emission zones and two documents on reducing emissions from vehicles. The revised policy guidance, issued to all local authorities in Wales and new technical guidance document, issued to all local authorities in the UK can be found at

Updated tools for LAQM purposes can be found at

Update to the VCM web portal
Published Date: 06/05/2009

A small error in the model equation has been identified and was corrected on 28th April 2009. This error concerned the temperature and pressure correction applied to the reported TEOM concentrations. This resulted in an underestimation of the TEOMVCM concentration of approximately 4% at background locations; an analysis of the impact of this error on the 2007 AURN measurements can be seen here.

Concentrations calculated using the VCM before this date should therefore be recalculated. To help with this process the correction xls spreadsheets that have been generated using the VCM Web Portal have been regenerated and can be downloaded from

Unfortunately, the details for all the corrections made are not available to us, specifically, if you made more than one correction in a visit to the web portal then only the last correction made will have been saved. We apologise for the inconvenience caused. This error affects the application of the VCM to TEOM measurements through the VCM web portal. It does not affect the underlying basis of the VCM and its proven equivalence to the EU reference method.

Website Upgrade Launched
Published Date: 27/03/2009

An upgraded version of this website has been launched today, incorporating the much more user-friendly Google Maps interface into the Home Page of the website. Also for the first time we are providing the latest data from the Welsh Air Quality Database in real-time to Google Earth. The instructions for Google Earth installation and download of the KMZ file can be found below the map on the website home page.

Widespread Increase in PM10 Particulate concentrations March 18th - 22nd 2009
Published Date: 27/03/2009

During the recent spell of warm weather many of you will have noticed that visibility was fairly poor with a distinct haze being observed across both urban and rural areas of Wales.

Our analysis of measurements from the Welsh Air Quality Database has shown that this coincided with a large increase in measured PM10 and PM2.5 concentrations, as illustrated in the PM10 graph and the PM2.5 graph. A large proportion of the particulates were also measured as being in the volatile fraction – a sure indication that they were most likely to be particulate nitrate from long-range transport of pollution. Sure enough our analysis of the air sources (click here to see plot) shows that the air reaching Wales was coming across from Northern Europe and southern England, probably bringing this particulate pollution with it.

This incident was widespread across the UK, not only affecting Wales, but most parts of England and Scotland as well.

Consultation on local air quality management
Published Date: 11/01/2009

The Welsh Assembly Government are seeking views on draft policy guidance for local authorities in Wales on their local air quality management duties under Part IV of the Environment Act 1995.

The draft guidance is intended to help local authorities to improve the service they provide in tackling poor air quality by targeting resources to work towards air quality objectives.
The consultation includes practice guidance on:

  • economic principles for the assessment of local measures to improve air quality;
  • low emission zones;
  • measures to encourage the uptake of low emission vehicles; and
  • measures to encourage the uptake of retro-fitted abatement equipment on vehicles .
After the consultation, the final guidance will be issued by the Welsh Ministers under section 88(1) of the Environment Act 1995. Local authorities will have to consider this guidance when carrying out their local air quality management duties under section 88(2) of the 1995 Act.

The guidance can be found at the Welsh Assembly Government's website at here.

Responses should be received by 02 March 2009.

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