Towards a harmonized procedure for the declaration of sound power levels within Directive 2000/14/EC

The Work Group of European Notified bodies 2000/14/EC which was established in 2004, recognized the urgent necessity to provide support for a more uniform and coherent implementation of the 2000/14/EC Directive. In this respect, a Sub-Group was created, called Statistics-Sub-Group (SWG), with the main task of verifying the possibility of finding common rules for the assessment of the declared sound power levels. This paper presents the results of a survey carried out by this group among the European notified bodies, in order to collect information both on the statistical formulas currently used for the calculation of the expanded uncertainty K and on the activities that authorities are performing in the different Member States on market surveillance.