# The Air Quality Standards (Wales) Regulations 2007, Paragraph 3: Requirements for air quality models


Where an air quality model is used for assessment, references to descriptions of the model and information on the uncertainty must be compiled. The uncertainty for modelling is defined as the maximum deviation of the measured and calculated concentration levels, over a full year, without taking into account the timing of the events.

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Source: https://www.legislation.gov.uk/wsi/2007/717/schedule/7/paragraph/3 (the official version)
Page: https://openlegislation.uk/air-quality-standards-wales-regulations-2007/schedule-7/paragraph-3
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.