The Norwegian Noise The Norwegian Noise Annoyance CalculationsAnnoyance Calculations

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Background

• The national target for noise reduction: By 2010 noise annoyance shall be reduced by 25 per cent from the 1999 level.

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Statistics Norways noise model

• Calculates data for noise impact and annoyance, in Norway for 1999 and following years.

• Estimates the noise from– road traffic– aircraft– railways– industry

• Results given as – Noise Annoyance Index (SPI)

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Measuring noise annoyance

• Noise annoyance differs

• with the source of noise– 60 dB of aircraft-noise more annoying than 60 dB of

railroad-noise

• from person to person– at the same noise level some will be higly annoyed, some

not annoyed at all.

• Development of the Average Annoyance Score

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Average annoyance score- dose-respons curve based on respondents describing

their annoyance due to noise

- estimates on a scale from 0-1 how annoyed an average person will be by noise from a particular source

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0,2

0,4

0,6

0,8

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20 30 40 50 60 70 80 90

Noise (dB)

No

ise

ann

oya

nce

Road traff ic

Air traff ic

Railw ay

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Noise Annoyance Index (SPI)• calculated by multiplying the number of exposed

persons within each noise-level with the average annoyance-score for this level.

• f.ex– 100 persons exposed to 60 dB– from Aircraft: (1,83 x (60dB – 38))/100 = 40– from Railroad: (1,19 x (60dB – 36))/100 = 29

Annoyance scores from different noise levels and sources can be added together to give a total level of annoyance for a community.

The noise model in general

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Calculation of railroad noise• Noise emission calculated

– by the Nordic prediction method for railroad noise – on the basis of

train type trainlength during 24h (meter) speed (km/h)

• Result: – each railroadlink identified by a code and the first and last

kilometer of the link, desibel-level generated

• Distributed along a geographic railroad-layer– using dynamic segmentation– on the basis of a railroad link code, and the first and last

kilometers

Dynamic segmentation; Applying noise level to geography

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Noise emission; Norwegian railroad network

Noise level connected to adresses

distance railroad-adress measurred

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Noise at adress level

• Calculating noise reduction due to – divergence (4 dB per. doubling of distance)– air absorbsion – correction for track conditions– if the receving adress is an appartment building– shielding from buildings in the neighbourhood

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Calculation of shielding

• Calculated for each adress individually

• Calculated on the basis of buildings between adress and railroad– the buildings coordinates – build-up area

• Calculates– radius of the buildings base– distance from adress to building– the part of an 180o view angel that the buildning will shield

Shielding from buildings

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Calculation of road traffic noise

• Simmilar to the railroad calculations, except..

• The calculations are being done for one type of road at the time– european roads– national roads– county roads– local roads

• An adress is assigned the highest noise value that reaches the adress

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Calculation of aircraft noise

• NORTIM-files– noise levels in a point grid

• Used for calculation of– emission of noise– diffusion over the ground

• Noiselevel updated from trafficnumbers and noise prognoses

• Adresses connected to the nearest point in the grid

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Calculation of industry noise• buisnesses (buisness

register) located in industry buildnings (GAB)

• assigned a noiselevel dependent on NACE-code

• rate of change dependent on density of buildings within ...? meters

• adress is assigned the highest noiselevel that reaches it