# The Air Quality Standards (Wales) Regulations 2007, Paragraph 3: Group A pollutants (other than benzene and carbon monoxide) and PM2·5


The accuracy for modelling and objective estimation is defined as the maximum deviation of the measured and calculated concentration levels, over the period considered by the limit value, without taking account the timing of the events

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Source: https://www.legislation.gov.uk/wsi/2007/717/schedule/8/paragraph/3 (the official version)
Page: https://openlegislation.uk/air-quality-standards-wales-regulations-2007/schedule-8/paragraph-3
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.