scope:

The European Framework Directive on Ambient Air-quality Assessment and Management, and its related Daughter Directives, require measurements to be made using specified Reference Methods (given in outline in Annex A of this Report), and the results to be reported, on specific air pollutants, with specified data quality objectives, by all Member States within the EU. The main purpose of this CEN Report is to provide guidance to those CEN/TC 264 working groups which are involved in the preparation of Reference Methods to measure ambient air quality as required by the EC Daughter Directives, on the uncertainty evaluation to be carried out in order to conform to these data quality objectives. One further purpose of this Report is to emphasize the essential requirements for appropriate quality assurance (QA) and quality control (QC) procedures in order to ensure that the ongoing field measurements are valid - so as to ensure the EC data quality objectives continue to be met.