# Directive 2004/107/EC of the European Parliament and of the Council of 15 December 2004 relating to arsenic, cadmium, mercury, nickel and polycyclic aromatic hydrocarbons in ambient air, Division II: Requirements for air quality models

Extent: E+W+S+N.I.

Where an air quality model is used for assessment, references to descriptions of the model and information on the uncertainty shall 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/eudr/2004/107/annex/IV/division/II (the official version)
Page: https://openlegislation.uk/eu-directive-2004-107/annex-IV/division-II
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.