Measuring noise in Amsterdam

What is the noise intensity level in Amsterdam? In the past months, citizens in Amsterdam have measured their environment with the Smart Citizen Kit. One of the measurements concerned the noise level at their location (when being in the range of the microphone - above 50dB). With the noise data of the kits that produced at least a complete week of data we created a map of all kits with the corresponding average levels per part of the day. 

We used the quantification of the Dutch RIVM institute: green in the visualisation means 'reasonable' (50-55 dB), yellow stands for 'moderate to bad' (55-65 dB) and red for 'very bad' (> 65 dB). It is directly visible that the inner city more often reaches the red levels.

Sometimes there is a clear connection between the daily levels and the function of a building - like the school where the levels are higher in the afternoons during schooldays. At the Waag on the Nieuwmarkt the levels are always red, but a remark has to be made that works on the foundation of the building were carried out in this period.