High-speed ferry noise zone
In spatial planning, the authorities designate a noise zone around high-speed ferries and other noise sources, where the noise level exceeds the recommended noise limit. Below is a review of recommended noise limits for high-speed ferries.
Statutory Orders no. 821 of 23. October 1997 lays down rules for granting of environmental permits to high speed ferries.
The limit values for low frequency noise inside dwellings are:
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Low frequency noise level (A-weighted level: 10-160 Hz)
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Rooms for occupation in dwellings, kindergartens etc.
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Evening/night (6pm-7am)
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25 dB
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Day (7am-6pm)
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30 dB
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Offices, rooms for teaching and similar noise sensitive use
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35 dB
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Other rooms in enterprises
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40 dB
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The limit values apply to the A-weighted level of the noise in the frequency range 10–160 Hz, measured or calculated as the equivalent level over two minutes indoor, in the most exposed room.
In addition there are also limit values for the "normal" noise from high speed ferries, both for the average noise level (expressed as L den ) and for the maximum A-weighted level, L max . These have been found to be considerably less restrictive than the limits for the low frequency noise.
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Equivalent level L DEN
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Maximum level L AFmax
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Dwelling areas and noise sensitive buildings for public use (schools, hospitals, nursery homes, etc.)
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55 dB
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70 dB
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Scattered dwellings in the open country
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55 dB
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70 dB
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Commercial purposes (hotels, offices, etc.)
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60 dB
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75 dB
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Recreational purposes with overnight residence (holiday cottages, allotment gardens, camping sites, etc.)
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50 dB
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65 dB
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Other recreational purposes, not for staying overnight
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55 dB
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70 dB
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