City traffic noise - a local or global problem?

According to the EU Green Paper on Noise policy, approx. 20% of the EU population is exposed to outdoor noise levels exceeding 65 dB (equivalent A-weighted daytime levels) and a little more than 40% is exposed to levels between 55 and 65 dB. The main source is then city traffic noise caused by cars, trucks, buses, trams, and trains. The situation in other industrialised countries is very much similar. This actual situation should be compared to the longterm goal for maximum noise exposure of the citizens. These goals are in most cases formulated as outdoor equivalent levels; in some cases as 24 hour levels, in others in separate daytime and nighttime levels. In several countries in Europe the goal implies 24 hour levels of the order LAeq<55 dB. This corresponds to a situation where a substantial fraction of the population is judged to be annoyed or seriously annoyed by the noise. To achieve this goal, it is demanded to accomplish a typical noise reduction of the order of 10 dB or more. For dwellings facing main roads the necessary noise reduction is of the order 20 dB. For the covering abstract see IRRD E104312.