Directive 2008/50/EC of the European Parliament and of the CouncilShow full title

Directive 2008/50/EC of the European Parliament and of the Council of 21 May 2008 on ambient air quality and cleaner air for Europe

3.Information on ambient concentrations of sulphur dioxide, nitrogen dioxide, particulate matter (at least PM10), ozone and carbon monoxide shall be updated on at least a daily basis, and, wherever practicable, information shall be updated on an hourly basis. Information on ambient concentrations of lead and benzene, presented as an average value for the last 12 months, shall be updated on a three-monthly basis, and on a monthly basis, wherever practicable.U.K.