These regulations are made in the implementation in Scotland of Council Directive 96/62/EC on ambient air quality assessment and management, and Council Directive 99/30/EC relating to limit values for sulphur dioxide, nitrogen dioxide and oxides of nitrogen, particulate matter and lead “the relevant pollutants" in ambient air.

Regulation 3 places the Scottish Ministers under a duty to take the measures necessary to ensure that in each zone in Scotland concentrations of relevant pollutants do not exceed limit values. The limit values for each pollutant, and the date by which they are to be met, are set out in Schedule 1.

Regulation 4 requires that the Scottish Ministers ensure that ambient air is assessed for each zone.

Regulation 5 requires them to classify each zone in relation to each of the relevant pollutants.

Regulation 5 together with Schedule 2 provide for the determination of upper and lower assessment thresholds for each relevant pollutant, and regulation 5 sets out the requirements for measurement or other assessment of air quality depending on pollution levels in relation to these thresholds.

Regulation 6 places a duty on the Scottish Ministers to review the classification of zones every five years or in the event of significant changes affecting levels of any of the relevant pollutants.

Regulation 7 requires the Scottish Ministers to ensure that specified methods are used for assessing air quality for each pollutant in each zone. Schedule 3 sets out how sampling points for the relevant pollutants are to be determined. Schedule 4 sets out criteria for the minimum number of sampling points for fixed measurements to assess compliance with limit values in zones where that is the only source of information, and with limit values for the protection of ecosystems or vegetation in certain other zones. Schedule 5 makes provision for data quality objectives for the required accuracy of assessment methods, and for compilation of the results of air quality assessment. Schedule 6 prescribes reference methods for the analysis, sampling or measurement of the relevant pollutants. Regulation 7 also places a duty on the Scottish Ministers to ensure that measuring stations supply data on concentrations of PM_2.5 particulate matter.

Regulation 8 requires the Scottish Ministers to draw up action plans indicating measures to be taken in the short term where there is a risk that limit values for any of the relevant pollutants, or alert thresholds for sulphur dioxide or nitrogen dioxide, will be exceeded. The alert thresholds for sulphur dioxide and nitrogen dioxide are set out in paragraph 1.2 of Part I and paragraph 2.2 of Part II of Schedule 1.

Regulation 9 requires the Scottish Ministers to draw up lists of zones where the levels of one or more of the relevant pollutants is above the limit value, or between the limit value and any margin of tolerance shown in Schedule 1. For such zones, regulation 9 places a duty on the Scottish Ministers to draw up a plan or programme, which must contain at least the information set out in Schedule 7 (including the location and origin of the pollution, the responsible authorities and the measures taken to deal with the pollution).

Regulation 10 requires the Scottish Ministers to list zones where levels of the relevant pollutants are below limit values, to ensure that levels of these pollutants are maintained below the limit values, and to endeavour to preserve the best ambient air quality, compatible with sustainable development.

Regulation 11 requires the Scottish Ministers to ensure that up-to-date information on ambient concentrations of each of the relevant pollutants is routinely made available to the public. It prescribes the frequency and content of such information. Where alert thresholds for sulphur dioxide or nitrogen dioxide are exceeded, further information, set out in paragraphs 1.3 of Part I and 2.3 of Part II of Schedule 1 must be provided (this includes details of the place and time of the occurrence, forecasts, and precautions to be taken by sensitive populations).

Regulation 12 revokes for Scotland and at different dates, parts of the Air Quality Standards Regulations 1989 giving effect to limit values for the relevant pollutants in earlier directives. The Air Quality Standards Regulations 1989, in turn implemented Council Directive 80/779/EEC on air quality limit values and guidelines for sulphur dioxide and suspended particulates; Council Directive 82/884/EEC on a limit value for lead in the air; and Council Directive 85/203/EEC on air quality standards for nitrogen dioxide. These Directives are repealed, with transitional provisions lasting up to 2005 and 2010, by Council Directive 99/30/EC.

A number of provisions of existing legislation confer powers on public bodies which are relevant to the achievement of limit values for sulphur dioxide, nitrogen dioxide and oxides of nitrogen, particulate matter and lead in ambient air. The most notable of these are–

A series of vehicle emission regulations transposing EC Directives impose limits on vehicle emissions including: S.I. 1992 No. 2137 (covering 91/441/EEC and 91/542/EEC); S.I. 1993 No. 2199 (covering directive 93/59/EEC); S.I. 1995 No. 2210 (covering directive 94/12/EC); S.I. 1997 No. 1544 (covering 96/69/EC) and S.I. 2000 No. 3197 (covering directive 98/69/EC). Environmental standards for fuel were set in 1994 (S.I. 1994 No. 2295) and 1999 (S.I. 1999 3107).

A full account of all the measures through which achievement of limit values will be sought is set out in the “Air Quality Strategy for England, Scotland, Wales and Northern Ireland" published by the Department of the Environment, Transport & the Regions, Scottish Executive, National Assembly for Wales and Northern Ireland Assembly, January 2000 (SE 2000/3), available from the Scottish Executive, Air, Climate and Engineering Unit (Air Quality Team), 1-H Victoria Quay, Edinburgh, EH6 6QQ and at http://www.scotland.gov.uk