The three methods of calculating population exposure according to CNOSSOS-EU

Abstract

In December 2020, the EU commission published amendments on CNOSSOS-EU in report 'C(2020) 9101 final'. In this report an additional method for the calculation of population exposure is described, based on a Median value. In the original CNOSSOS document, 2 methods are described, Method 1 - Most exposed façade and Method 2 - Length of representative façade. Method 1 is used for buildings that represent a single dwelling or 1 dwelling per floor. Method 2 is used for apartment buildings that have dwellings with a single façade exposed to noise. The new Method 3 can be used for apartment buildings that have more than 1 façade exposed to noise, or for apartment buildings where no information on how many facades are exposed to noise is available. It will be difficult for authorities to create a dataset that distinguishes between a single façade and multiple façades exposed to noise. Therefore, it seems likely that Method 3 will be more frequently used. When comparing Methods 2 and 3, it is found that Method 3 leads to a higher number of exposed people and dwellings. In this paper the 3 methods are explained and compared using noise and population data for a city in Europe.