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Conference_programme: 15.2 - The New CNOSSOS calculation method for environmental noise of road / railway / industrial noise

Lecture: Obstacles to the implementation of Cnossos in the Netherlands

Author(s): Kok Arnaud, Van Beek Annemarie, De Gruijter Dolf

By the end of 2018 all EU member states will have to implement Annex II of EU directive 2015/996 (commonly referred to as Cnossos) for strategic noise mapping in legislation. Many member states, including the Netherlands, are researching how to implement the Annex. In the Netherlands, policy makers wish to use a single calculation method for both permitting within the national legislation and noise mapping.\n\nIn 2017 we have completed a study which gave answers to the following two questions:\n1. What is needed to implement Cnossos for noise mapping\n2. Is Cnossos suited for permitting for road traffic, railway and/or industrial noise.\n\nAn important aspect in answering our questions was if results obtained with Cnossos are plausible and if they compare well to measurements. \n\nAs a result of our study we found some results that are not plausible. This led to the identification of a serious issue within the calculation method. It influences the results in urban areas and starts at a distance of about 200 meters from a source. The improbable results are caused by the way attenuation is calculated in favourable conditions, in cases where the propagation meets multiple diffraction points. This issue has led us to conclude that Cnossos, as it is, is not suited for either permitting or noise mapping.\nThis issue and 21 other, less dramatic, issues have currently been identified. It has been decided that a amendment of Annex II will be prepared. The Netherlands is willing to prepare proposal for revision of the Annex in a collaborative effort with other countries. \n\nIn our presentation we will talk about the process to implement Cnossos in Dutch legislation and the many issues we have found. We will also present the collaborative road map, and first results, to the revised Annex.\n

Corresponding author

Name: Dr Arnaud Kok

e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Country: Netherlands