noise is generally defined as -...

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noise is generally defined as unwanted sound

Situation/noise source SPL[dBA] pressure [µPa] Avg subj. descript.

30m from a military jet aircraft take off 140 200,000,000 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 90 630,000 Very noisy

Ringing alarm clock at 1m 80 200,000 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 30 630 Very quiet

Country location w/o any identifiable sound 20 200

Theoretical threshold of hearing 0 20 Uncanny silence

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

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)

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

other documents:

CONCAWE

EEMUA Noise procedure specification and guide 140&141

Minerals Planning Guidance MPG11

Planning Policy Guidance Note PPG24

ISO 9613-2 1996 Attenuation of sound during propagation outdoors

World Health Organisation Guidelines for Community Noise

Noise Emission in the Environment by Equipment for use Outdoors Regulations

Criterion Typical Situations Design Range

Good Reasonable

Reasonableresting/sleepingconditions

Living rooms 30 40

Bedrooms 30 35

The time period T should be appropriate for the activity involved (e.g. 2300 - 0700 for bedrooms)

For a reasonable standard in bedrooms at night, individual noise events (measured with FAST time weighting) should not normally exceed 45dB LAmax

Noise change dB(A) Impact

0 None

0 to 3 Slight

3 to 5 Moderate

5 to 10 Substantial

10 and above Severe

Noise Exposure Categories (PPG24)

A Noise need not be considered as a determining factor in grantingplanning permission, although the noise level at the high end of thecategory should not be regarded as desirable.

B Noise should be taken into account when determining planningapplications, and where appropriate, conditions imposed to ensurean adequate level of protection.

C Planning permission should not normally be granted. Where it isconsidered that permission should be given, for example, becausethere are no alternative quieter sites available, conditions should beimposed to ensure a commensurate level of protection against noise.

D Planning permission should normally be refused

Noise Source Noise Exposure Category (PPG24)

Time Period A B C D

Road Traffic 0700 – 2300 <55 55 – 63 63 – 72 >72

2300 – 0700 <45 45 – 57 57 – 66 <66

Rail Traffic 0700 – 2300 <55 55 – 66 66 – 74 >74

2300 – 0700 <45 45 – 59 59 – 66 >66

Air Traffic 0700 – 2300 <57 57 – 66 66 – 72 >72

2300 – 0700 <48 48 – 57 57 – 66 >66

Mixed Sources 0700 – 2300 <55 55 – 63 63 – 72 >72

2300 – 0700 <45 45 - 57 57 - 66 >66

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

main features of anenvironmental noise assessment:

baseline

prediction

assessment

mitigation

presentation

follow–up

BAT (Best Available Techniques) include:

costs and benefits

the technical characteristics of the

installation concerned

geographical location

local environmental conditions

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

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

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

CUW, UK

Noise levels dB(A)

< 30.030.0 <= < 35.035.0 <= < 40.040.0 <= < 45.045.0 <= < 50.050.0 <= < 55.055.0 <= < 60.060.0 <= < 65.065.0 <= < 70.070.0 <= < 75.075.0 <= < 80.080.0 <=

CUW-UK

Signs and symbolsRoad axis

Emission line

Surf ace

Main building

Area source

Point source

Length Scale 1:1000000 50 100 200 300 400

Porto Montenegroden noise lev el bef ore reconstruction 1

Noise levels dB(A)

< 30.030.0 <= < 35.035.0 <= < 40.040.0 <= < 45.045.0 <= < 50.050.0 <= < 55.055.0 <= < 60.060.0 <= < 65.065.0 <= < 70.070.0 <= < 75.075.0 <= < 80.080.0 <=

CUW-UK

Emission line

Surf ace

Main building

Area source

Point source

Length Scale 1:1000000 50 100 200 300 400

Porto Montenegroden noise lev el during reconstruction 5

Noise levels dB(A)

< 30.030.0 <= < 35.035.0 <= < 40.040.0 <= < 45.045.0 <= < 50.050.0 <= < 55.055.0 <= < 60.060.0 <= < 65.065.0 <= < 70.070.0 <= < 75.075.0 <= < 80.080.0 <=

CUW-UK

Emission line

Surf ace

Main building

Area source

Point source

Length Scale 1:1000000 50 100 200 300 400

Porto Montenegroden noise lev el af ter reconstruction 9

Noise levels dB(A)

< 40.040.0 <= < 42.042.0 <= < 44.044.0 <= < 46.046.0 <= < 48.048.0 <= < 50.050.0 <= < 52.052.0 <= < 54.054.0 <= < 56.056.0 <= < 58.058.0 <= < 60.060.0 <=

CUW-UK

Emission line

Surf ace

Main building

Area source

Point source

Length Scale 1:1000000 50 100 200 300 400

Porto Montenegroday noise lev el af ter reconstruction 13

HRAPAVOSTVoda, z0 = 0.0001mLedina, z0 = 0.03mŠuma, z0 = 0.3mNaselja, z0 = 1m

PRIJEMNICI BUKE1. Kličevac2. Rečica3. Ram4. Zatonje5. Ostrovo6. Biskuplje7. Kisiljevo8. Kurjače9. Popovac10.Topolovnik11.Majilovac

VGT1VGT2

VGT3VGT4

VGT7VGT8

VGT1 VGT2 VGT3 VGT4 VGT5 VGT6 VGT7 VGT8X (m) 5619.5 5579.5 5549.5 5500.5 5372.5 5174.5 4996.5 4838.5Y (m) 9070.4 8744.4 8458.4 8131.4 7825.4 7584.4 7301.4 7094.4Z (m) 214.6 250.8 276.8 306.3 306.5 281.2 255.7 233.8

KARAKTERISTIKE IZVORA BUKE

Tip VGT: ENERCON E-82Naznacena snaga:

2000 kWPrecnik rotora:

82 mVisina centra rotora lopatica:

138 mBroj lopatica: 3Površina koju prebrišu lopatice:

5281 m2

Obimna brzina: 6 – 19.5 o/minBrzina vrha lopatice: 25 – 80 m/sBrzina vetra pri ukljucenju:

2.5 m/sNaznacena brzina vetra:

12 m/s LwA,ref (Z=138m) 99.6 dB(A)

61.5Hz

dB(A) 81 86.4 95.6 94.0 88.3 82.9 71.8 99.6

Projekat vetrogeneratorske farme

"Veliko Brdo"

DirigentAcoustics

Length scale 1:5000000 0.250.5 1 1.5 2

Noise levels nightin dB(A)

< 1010 - 1313 - 1616 - 1919 - 2222 - 2525 - 2828 - 3131 - 3434 - 3737 - 4040 - 4343 - 4646 - 4949 - 52

Signs and symbols

Road axis

Emission line

Surface

Main building

Auxiliary building

Terrain edge

Point receiver

Point source

Noise map

1 - Kličevac2 - Rečica3 - Ram4 - Zatonje5 - Ostrovo6 - Biskuplje7 - Kisiljevo8 - Kurjače9 - Topolovnik10 - Majilovac

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20002000

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