Local air quality management: policy guidance

Updated guidance for local authorities to take account of changes to industrial emissions legislation and requirements.

9: Relationships between Local Air Quality Management and EU air quality legislation and policy

Local Air Quality Management and Directive 2008/50/ EC - key differences

9.1 Although LAQM and Directive 2008/50/ EC [15] on ambient air quality have the shared aim of improving human and environmental health through reducing air pollution, the rationale and approach employed in each system have some quite important differences.


9.2 Under LAQM the standards are defined as objectives, whereas in the Directive they are limit or target values. This different wording reflects the differing legal status of the standards, as outlined in the following paragraph.

Legal responsibility

9.3 As explained in chapter 1 of this guidance, under the Environment Act 1995 and associated regulations, local authorities are required to review and assess air quality in their areas against objectives for several air pollutants of particular concern for human health. Authorities are not legally obliged to achieve the objectives by the required dates, but to demonstrate they are doing all that is reasonably possible to work towards them. This is because some pollution sources are outwith direct local authority control, for example Transport Scotland controlled trunk roads and SEPA regulated processes. However authorities are expected to liaise with these and other relevant organisations when developing action plan measures.

9.4 In contrast, the Scottish Government and the other UK administrations are responsible for securing compliance with the Directive limit values. In this case, the requirements are legally binding and EU Member States are potentially liable to infraction if any limit value is not achieved by the required date and a time extension has not been agreed. Local authorities have no legal responsibility in relation to the Directive, even though the work undertaken by authorities through LAQM makes an important contribution to actions being implemented by central government.

Attainment dates

9.5 In most cases, the attainment dates are identical for LAQM objectives and Directive limit values. There are some differences, most notably for the Scottish PM10 objectives, however as these attainment dates are now passed the differences are largely academic.

Scope of assessment

9.6 Under LAQM, assessment is required in locations where members of the public are regularly present and there is exposure to the pollutant in question over the timescale for which the objective is defined. The Directive requirements are slightly different and assessment is undertaken anywhere the public has access, irrespective of whether this is regular access. The exceptions are workplaces which are covered by health and safety legislation, locations with no fixed habitation, and road carriageways and central reservations (unless there is public access to the central reservation).

Assessment methodology

9.7 Monitoring requirements are defined more precisely in the Directive than for the purposes of LAQM. The Directive requires Scotland to be divided into zones and agglomerations based on population (an agglomeration is defined as a zone if it is a conurbation of greater than 250,000 inhabitants). Within each zone/agglomeration there is a minimum number of sampling points for each pollutant and also a provision for reducing these by up to 50% if modelling can be shown to provide equivalent data of a sufficient quality. In addition, there are detailed criteria for sampling locations, including that traffic related sites should be representative of air quality for a street segment no less than 100m in length. Finally, there is a requirement to use reference monitoring equipment as specified in the Directive, or alternatively equipment that can be shown to be equivalent to the reference methods.

9.8 For LAQM monitoring, although detailed requirements are set out in the technical guidance TG (16), there is more flexibility as to where monitoring sites can be located and greater scope for tailoring monitoring to specific local circumstances. Also, there is no legally defined requirement to use reference or equivalence methods although this is strongly encouraged and is the Scottish Government's preferred approach.

9.9 These differences in assessment methodology are why it is difficult to directly compare LAQM review and assessment with work undertaken by central government to assess compliance with the Directive. It is also the reason why it is not always possible to incorporate local authority monitoring sites into the AURN. The two systems are set up for different purposes, with LAQM by definition focusing much more on the local situation. The apparent anomaly between the large number of AQMAs which remain in Scotland and the conclusion that we are almost fully compliant with the Directive requirements is simply a reflection of these differences. Using LAQM data to supplement UK Government submissions to the European Commission also requires careful consideration due to the very specific requirements of the Directive and explains why, historically, this has only been done in a very limited way.



Directive 2008/50/ EC


Local authorities

Central government

Legal status

Achievement of objectives not legally binding, but review and assessment process is mandatory

Achievement of limit values legally binding


Relevant public exposure

Anywhere with public access


Reference or equivalence monitors recommended

Reference or equivalence monitors mandatory

Monitor number

Undefined, depends on local circumstances

Defined number of monitors, or modelling equivalent for up to 50% of monitoring points, based on population

Monitor locations

Defined in guidance

Defined in legislation, supplemented by guidance


Designed to assess local circumstances

Designed to give a broad overview

EU Clean Air policy package

9.10 At the conclusion of the 2013 EU Year of Air, during which a comprehensive review of legislation and policy was undertaken, the European Commission announced details of its clean air policy package [16] . Although implementation of this package falls largely on central government, there may be some implications for and input requirements from local authorities. Authorities should therefore familiarise themselves with the details of the package, which are summarised below.

9.11 Directive 2008/50/ EC on ambient air quality and clean air for Europe will not be revised in the short term, therefore there will be no changes to current limit and target values. Instead, the focus is on ensuring that full compliance with the Directive is secured as soon as possible. A new Clean Air Programme for Europe contains measures to ensure that existing targets are met in the short term. The package also includes support measures to help cut air pollution, with a focus on improving air quality in cities, supporting research and innovation, and promoting international co-operation.

9.12 The National Emission Ceilings Directive will be updated to incorporate the new targets agreed under the revised Gothenburg Protocol to the Convention on Long Range Transboundary Air Pollution. Increasingly stringent emissions ceilings will also be proposed for 2025 and 2030. Finally, there is a new Directive to control emissions from small and medium sized combustion plants between 1 and 50 MW.


Back to top