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NOISE POLLUTION CHAPTER 9 Matakuliah: S0782 - Teknik Lingkungan Tahun: 2009.

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Presentasi berjudul: "NOISE POLLUTION CHAPTER 9 Matakuliah: S0782 - Teknik Lingkungan Tahun: 2009."— Transcript presentasi:

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2 NOISE POLLUTION CHAPTER 9 Matakuliah: S Teknik Lingkungan Tahun: 2009

3 Bina Nusantara University 3 Definisi Noise (bising) adalah bunyi yang tidak dikehendaki, suatu gejala lingkungan (environmental phenomenon) yang mempengaruhi manusia sejak dalam kandungan dan sepanjang hidupnya. Bising: setiap bunyi yang dapat mengakibatkan pengaruh fisiologis dan psikologis pada individu dan dapat mengganggu kehidupan sosial individu atau kelompok. Bising pada intensitas dan lama waktu tertentu dapat mempengaruhi hilangnya pendengaran secara sementara (temporary) atau tetap (permanen) dari ketulian yang ringan sampai tuli secara total.

4 Bina Nusantara University 4 Gelombang Bunyi Dihasilkan oleh getaran dari benda-benda padat atau pemisahan cairan yang bergerak sekitar atau memalui lubang dalam benda padat. Getaran dan atau pemisahan ini menyebabkan udara disekelilingnya mengalami tekanan (compression) dan pelepasan tekanan (rare faction) secara bergantian, seperti getaran torak/ piston dalam tabung. Perubahan tekanan yang silih berganti ini menghasilkan bunya yang diterima oleh telinga.

5 Typical Sound Levels L A in dBAExample 0Threshold of hearing 50Residence 60Conventional Speech 70Street Traffic at 100 ft 74Passing Automobile at 20 ft 80Light Trucks at 20 ft 120Loud Rock and Roll Band 140Jet plane on ground at 20 ft (Adapted from Cantor,1996)

6 Bina Nusantara University 6 Effect of Environmental Noise on People Interferes with human activities and psychological annoyance –sleep disturbance –disruption of speech communication –disruption of tasks requiring concentration or coordination –mental and physical health effects Effects depend on: –number of noise events that occur during a time interval –peak sound pressure levels reached during the events –degree to which peak levels exceed average noise level

7 Bina Nusantara University 7 Community Reaction to Noise Several factors (other than magnitude of exposure) influence community reaction to intruding noise: –Duration and frequency of occurrence of noise –Time of year of noise –Time of day of noise –Background noise level –History of prior exposure to intruding noise –Attitude toward the noise source

8 Bina Nusantara University 8 Reported Thresholds for Noise Nuisance Reported by World Health Organization: -at 55 to 60 dBA noise creates annoyance -At 60 to 65 dBA annoyance increases considerably -At > 65 dBA constrained behaviour patterns

9 Bina Nusantara University 9 Addition of Noise From Several Sources: Noise doesn’t add linearly! L T = total sound level (dBA) L i = individual component sound level resulting from source i (dBA)

10 Bina Nusantara University 10 Temporal Aspects L eq : Equivalent Sound Level - energy equivalent sound pressure level averaged over a specific time period (i.e. 24 hrs) -used to account for temporal variations in sound L i = individual component sound level during interval i (dBA) f i = time fraction of interval i

11 Bina Nusantara University 11 L dn : Day-Night Average Sound Level -equivalent to a 24 hr L eq except that 10 dBA weighting penalty is added to noise during nighttime period (22: :00) before computing average -Based on studies that have shown people are more disturbed by night-time sound

12 Typical Day-Night Noise Levels Description Typical Range of L dn, dBA Average L dn, dBA Quiet suburban residential 48 to 5250 Normal suburban residential 53 to 5755 Urban residential58 to 6260 Noisy Urban Residential63 to 6765 Very noisy urban residential 68 to 7270 (Adapted from Cantor,1996)

13 Bina Nusantara University 13 Sound Attenuation Sound pressure level decreases with increasing distance from a source as sound waves radiate outward. For a point source: Example: Construction equipment r 1 = distance from source to nearer pt. (m) r 2 = distance from source to farther pt. (m)

14 Bina Nusantara University 14 Sound Attenuation – Line Source Line source can be treated as a series of point sources: Example: Roadways l 1 = distance from source to nearer pt. (m) l 2 = distance from source to farther pt. (m)

15 Bina Nusantara University 15 Estimates of Noise at Construction Sites for Public Works, Roads and Highways Construction Phase All Equipment at Site Minimum Equipment at Site Ground Clearing84 Excavation8878 Foundations88 Erection7978 Finishing84 (Adapted from Cantor,1996)


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