noise is generally defined as unwanted sound

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2 noise is generally defined as unwanted sound

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4 Situation/noise source SPL[dBA] pressure [µpa] Avg subj. descript. 30m from a military jet aircraft take off ,000,000 Painful, intolerable Pop concert 105 3,500,000 Night club 100 2,000,000 Pop concert at mixer desk 98 1,600,000 Passing heavy goods vehicle at 7m ,000 Very noisy Ringing alarm clock at 1m ,000 Wake up sound Domestic vacuum cleaner at 3m 70 63,000 Noisy Business office 60 20,000 Normal conversation at 1m 55 11,000 The reading room of the British Museum 35 1,100 Bedroom in a quiet area with the windows shut Very quiet Country location w/o any identifiable sound Theoretical threshold of hearing 0 20 Uncanny silence

5 the sound level falls with increasing distance from the source doubling the distance from a point source produces a reduction in sound level of 6dB if the distance from the line source doubles, then the sound pressure halves, that is, 3dB per doubling of distance

6 when sound is incident on a building (or any acoustically hard surface) a major portion can be reflected back off the façade rather than absorbed if the receiver is the occupier of a building, it is the level at the façade, usually 1m in front of it, that should be measured (calculated)

7 Relevant methodologies for noise measurement and evaluation BS 4142:1997 Method for rating industrial noise affecting mixed residential and industrial areas BS 5228:1997 Noise and vibration control on construction and open sites BS 7445:1991 Description and measurement of environmental noise BS 8233:1999 Sound insulation and noise reduction for buildings Code of Practice

8 other documents: CONCAWE EEMUA Noise procedure specification and guide 140&141 Minerals Planning Guidance MPG11 Planning Policy Guidance Note PPG24 ISO Attenuation of sound during propagation outdoors World Health Organisation Guidelines for Community Noise Noise Emission in the Environment by Equipment for use Outdoors Regulations

9 Criterion Typical Situations Design Range Reasonable resting/sleeping conditions Good Reasonable Living rooms Bedrooms The time period T should be appropriate for the activity involved (e.g for bedrooms) For a reasonable standard in bedrooms at night, individual noise events (measured with FAST time weighting) should not normally exceed 45dB LAmax

10 Noise change db(a) Impact 0 None 0 to 3 Slight 3 to 5 Moderate 5 to 10 Substantial 10 and above Severe

11 Noise Exposure Categories (PPG24) A B C D Noise need not be considered as a determining factor in granting planning permission, although the noise level at the high end of the category should not be regarded as desirable. Noise should be taken into account when determining planning applications, and where appropriate, conditions imposed to ensure an adequate level of protection. Planning permission should not normally be granted. Where it is considered that permission should be given, for example, because there are no alternative quieter sites available, conditions should be imposed to ensure a commensurate level of protection against noise. Planning permission should normally be refused

12 Noise Source Noise Exposure Category (PPG24) Time Period A B C D Road Traffic < > < <66 Rail Traffic < > < >66 Air Traffic < > < >66 Mixed Sources < > < >66

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14 noise predictions can be useful in three circumstances: at a proposed facility where noise must be quantified before construction to ensure that no noise problems will arise from the installation once it is operational, and to allow Permit noise limits to be set if necessary at existing installations where the effectiveness of various noise control techniques needs to be reviewed and to establish a target Permit level that takes BAT into account at existing installations where changes to operations or the process are proposed

15 main features of an environmental noise assessment: baseline prediction assessment mitigation presentation follow up

16 BAT (Best Available Techniques) include: costs and benefits the technical characteristics of the installation concerned geographical location local environmental conditions

17 noise levels at sensitive receptors can be minimized by: reduction at source ensuring adequate distance between the source and receiver the use of barriers between the source and receiver

18 The amount of noise radiated depends on: the sound power level of the source the nature of the building structure gaps in the fabric of the building the number of sources

19 The noise received depends on the degree of attenuation provided by: distance from source attenuation provided by the type of ground screening by walls, banks, other buildings the wind direction meteorological conditions, such as temperature inversions and gradients atmospheric absorption

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23 Porto Montenegro den day noise lev el after during bef ore reconstruction Noise levels db(a) <30.0 < <= <35.0 < <= <40.0 < <= <45.0 < <= <50.0 < <= <55.0 < <= <60.0 < <= <65.0 < <= <70.0 < <= <75.0 < <= <80.0 < <= ,2 Signs and symbols Road axis Emission line Surf ace Main building Area Area source Point source Length Scale 1: m CUW-UK

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32 3 HRAPAVOST Voda, z 0 = m Ledina, z 0 = 0.03m Šuma, z 0 = 0.3m Naselja, z 0 = 1m PRIJEMNICI BUKE 1. Kličevac 2. Rečica 3. Ram 4. Zatonje 5. Ostrovo 6. Biskuplje 7. Kisiljevo 8. Kurjače 9. Popovac 10. Topolovnik 11. Majilovac

33 KARAKTERISTIKE IZVORA BUKE Tip VGT: ENERCON E- 82 Naznacena snaga: 2000 kw Precnik rotora: 82 m Visina centra rotora lopatica: 138 m Broj lopatica: 3 Površina koju prebrišu lopatice: 5281 m 2 Obimna brzina: o/min Brzina vrha lopatice: Brzina vetra pri ukljucenju: 2.5 m/s Naznacena brzina vetra: 12 m/s LwA,ref (Z=138m) VGT m/s VGT db(a) VGT6 VGT5 VGT4 VGT3 VGT2 VGT1 VGT1 VGT2 VGT3 VGT4 VGT5 VGT6 VGT7 VGT8 X (m) Y (m) Z (m) Hz Hz Hz khz khz khz khz Zbir db(a)

34 Projekat vetrogeneratorske farme "Veliko Brdo" Noise map 1 - Kličevac 2 - Rečica 3 - Ram 4 - Zatonje 5 - Ostrovo 6 - Biskuplje 7 - Kisiljevo 8 - Kurjače 9 - Topolovnik 10 - Majilovac Map Noise levels night Signs and symbols in db(a) Road axis < >= 52 Emission line Surface Main building Auxiliary building Wall Terrain edge Point receiver Point source 5500 Length scale 1: Dirigent Acoustics 2 km

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