# The Air Quality Standards (Wales) Regulations 2010, Regulation 13: Duty in relation to limit values

Extent: E+W

(1) Subject to paragraph (2), the Welsh Ministers must ensure that levels of sulphur dioxide, nitrogen dioxide, benzene, carbon monoxide, lead, PM10 and PM2·5 do not exceed the limit values set out in Schedule 1 in any zone.
(2) Where the date for achieving the limit values for nitrogen dioxide is postponed in any zone in accordance with regulation 15(2), the Welsh Ministers must ensure that the level of nitrogen dioxide in that zone does not exceed the limit value for that pollutant set out in Schedule 1 by more than 50%.
(3) In zones where the level of any pollutant mentioned in paragraph (1) is below the limit value set out in Schedule 1 for that pollutant, the Welsh Ministers must ensure that the level of that pollutant is maintained below that limit value and must endeavour to maintain the best ambient air quality compatible with sustainable development.
(4) Where the Welsh Ministers consider that a limit value has been exceeded for a reason attributable to natural sources, that limit value will not be considered to be exceeded for the purposes of these Regulations.
(5) Where the Welsh Ministers consider that a limit value has been exceeded for a reason attributable to natural sources in accordance with paragraph (4), the Welsh Ministers must publish information, for the relevant zones and agglomerations, demonstrating that the exceedances are attributable to natural sources.

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Source: https://www.legislation.gov.uk/wsi/2010/1433/regulation/13 (the official version)
Page: https://openlegislation.uk/air-quality-standards-wales-regulations-2010/regulation-13
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.