Lukovnikova M., Van Dyck J.

The Outdoor Noise Directive (Directive 2000/14/EC) prescribes the permissible noise emission levels for equipment for use outdoors and specifies how noise emissions shall be measured, but does not define the procedure of verification and does not provide guidelines to the producers on how the declared noise emission should be determined in order to pass with high probability the verification. For the declaration and verification alternative recommendations have been issued: a strict approach that follows the relevant ISO standards and a lenient approach that is not based on standards. According to the industry application of the strict approach leads to unrealistically stringent product specifications. The declared value based on the lenient approach fails however in many cases the verification. To resolve this undesirable situation, the notified bodies providing service to the producers in the field of conformity assessment have formulated an alternative for the declaration and verification of the noise emission. The Belgian competent authority has reviewed this proposal and formulated consequently a compromise approach. This article compares the three different approaches (the standard approach, the proposal by the notified bodies and the compromise approach formulated by the Belgian competent authority). It will be shown that the compromise approach remains founded on a proper application of statistics, but leads to more realistic declared values. The compromise can be implemented easily and immediately. Inherent to the compromise is the request that the producers implement statistical process control methods and declare selected results to the European Commission. Analysis of these industry data will then allow in the longer term the application of the original standard methods without imposing unrealistic conditions on the industry.