The density curves show the distribution of the three main noise sources in Canton Zurich. Road noise, centred around 58 dB, is the most broadly distributed because it occurs almost everywhere. Aircraft noise (centred at 48 dB) is concentrated on the corridor around Kloten, rail noise (55 dB) on the rail corridors. Basis: FOEN noise-exposure cadastre, City of Zurich environmental report and LSV immission limits.
Properties directly on SBB lines reach 60+ dB at night; the night guideline of 45 dB (residential zone ES II) is often exceeded, especially in urban road-noise areas. If the immission limit is exceeded, there is a claim to sound-insulation windows.
A visit in the early morning and the evening is recommended. The official noise data can be retrieved free of charge for any property in the cantonal GIS (maps.zh.ch). Sources: FOEN noise-exposure cadastre, City of Zurich environmental report, LSV.