UNIT KEJURUTERAAN ALAM SEKITAR UNIT KEJURUTERAAN ALAM SEKITAR JABATAN KEJURUTERAAN AWAM JABATAN KEJURUTERAAN AWAM

POLITEKNIK SULTAN IDRIS SHAH

CHAPTER 6CHAPTER 6

SOURCES OF NOISE SOURCES OF NOISE POLLUTIONPOLLUTION

2

Upon completion of this course

, student should be able to :

Explain the sources of noise pollution Identify noise pollution in industry and

construction area Relate the effects of traffic and transportation to

noise pollution Explain domestic noise pollution Identify outdoor activities that can create noise

pollution

WHAT IS NOISE POLLUTION?Any unwanted sound that

penetrates the environment is noise pollution.In general noise pollution refers to any noise irritating to one's ear which comes from an external source.

Sources of noise pollution.

Industrial Commercial Social Cultural Transportation

Sources of noise pollution Street traffic Rail roads Airplanes Constructions Industry Domestic noise Outdoor

activities

SOURCES OF INDUSTRIAL NOISE

Aerodynamic from air movement, such as compressed air release or fan noise.

Impact, such as from hammering, components falling into bins or gear noise.

Stick – slip friction such as from lathe tools cutting or brake noise

Vibration and associated radiation from surfaces.

Industrial Noise refers to noise that is created in the factories which is jarring and unbearable. Sound becomes noise only it becomes unwanted and when it becomes more than that it is referred to as "noise pollution". Heavy industries like shipbuilding and iron and steel have long been associated with Noise Induced Hearing Loss (NIHL). 

Industrial NoiseIndustrial Noise

Industrial and commercial noise pollution. This is posing to be a big challenge with very

passing day and is a threat to safety and health of the people who are working in the industry and common people as well. It has been scientifically proved that noise more than 85 decibels can cause hearing impairment and does not meet the standards set for healthy working environment.

Industrial Noise resulting to noise pollution has many reasons such as industries being close to human habitats which prevents the noise from decaying before it reaches human ear. 

OSHA’S PERMISSITIE NOISE EXPOSURE LIMITS

Traffic noise

TRAFFIC NOISE(ROAD) When all transportation noise is

considered, more than half of all European Union citizens is estimated to live in zones that do not ensure acoustical comfort to residents.

At night, more than 30% are exposed to equivalent sound pressure levels exceeding 55 dB(A), which are disturbing to sleep.

TRAFFIC NOISE SOURCES AND PROPAGATION The following list provides information on the

types of transportation noise sources that will be part of a roadway project, and describes the type of noise each produces.

Passenger Vehicles (cars): Noise emitted from 0 to 2 feet above roadway,

primarily from tire-roadway interface. This category includes normal passenger vehicles,

small and regular pickup trucks, small to mid-size sport utility vehicles, mini- and full-size passenger vans.

Typical noise levels for passenger vehicles are 72 to 74 dBA at 55 mph at a distance of 50 feet.

Medium Trucks (MT): Noise emitted from 2 to 5 feet above roadway, combined

noise from tire-roadway interface and engine exhaust noise. This category includes delivery vans, large sport utility

vehicles with knobby tires, large diesel engine trucks, some tow-trucks, small to medium recreational motor homes and other larger trucks with the exhaust located under the vehicle.

Typical noise levels for medium trucks are 80 to 82 dBA at 55 mph at 50 feet.

Heavy Trucks (HT): Noise emitted from 6 to 8 feet above the roadway surface,

combined noise sources includes tire-roadway interface, engine noise, and exhaust stack noise.

This category includes all log-haul tractor-trailers, dump trucks, cement mixers, large transit buses, motor homes with exhaust located at top of vehicle, and other vehicles with the exhaust located above the vehicle.

Typical noise levels for heavy trucks are 84 to 86 dBA at 55 mph at 50 feet 2.

HINGAR LALU LINTAS Permukaan jalan Jenis jalan Kelembapan jalan Halaju kenderaan Nisbah laluan lori Kecerunan dan

persimpangan jalan Pembalikan pada

bangunan

FAKTOR YANG MEMPENGARUHI KEBISINGAN LALULINTAS

HINGAR LALU LINTAS

Hingar yang paling teruk di jalan raya adalah datang dari lori dan trak besar.Kebiasaanya hingar trak merangkumi semua jenis hingar lalu lintas.

Merekacipta kenderaan yang lebih senyap

Lalulintas dibina jauh dari tumpuan penduduk dan kawasan perumahan.

Membina dinding atau sawar yang boleh menyerap bunyi.

HINGAR LALU LINTAS

CARA UNTUK MENGURANGKAN HINGAR LALU LINTAS

a) PERMUKAAN JALAN DAN JENIS JALAN

JALAN YANG DIBUAT DARI KONKRIT ADALAH LEBIH BISING DARI ASPAL.

JALAN YANG BASAH LEBIH BISING BERBANDING JALAN YANG KERING.

b) KELAJUAN KENDERAAN KENDERAAN YANG LAJU MENGHASILKAN

BUNYI YANG SEMAKIN MENINGKAT. KENDERAAN YANG ENJIN LAMA AKAN

MENGHASILKAN BUNYI YANG TINGGI. KAJIAN MENDAPATI BAHAWA SEMAKIN

LAJU KENDERAAN SEMAKIN KUAT BUNYI BISING YANG DIHASILKAN DAN BERTAMBAH DARJAH KEBISINGAN.

c) NISBAH LALUAN LORI JIKA TERDAPAT BANYAK LORI MAKA AKAN

BERTAMBAH BUNYI KEBISINGAN YANG TERHASIL.

INI KERANA LORI YANG MEMBAWA BEBAN YANG BERAT AKAN MENEKAN MINYAK UNTUK MENGGERAKKAN KENDERAAN DAN IA AKAN MENJADIKAN BUNYI KUAT TERHASIL.CONTOH SEPERTI LORI BALAK DAN LORI AIS.

LORI MEMPUNYAI SISI YANG TINGGI.

d) KECERUNAN DAN PERSIMPANGAN JALAN

KECERUNAN YANG TINGGI AKAN AKIBATKAN BUNYI YANG KUAT TERHASIL.

SEMAKIN TINGGI CERUN AKAN BERLAKU SEMAKIN KUAT BUNYI BISING TERHASIL.

PERSIMPANGAN JALAN YANG PUNYAI LAMPU ISYARAT AKAN HASILKAN BUNYI YANG KUAT KERANA KENDERAAN BERADA DALAM STATIK.

e) PEMBALIKAN PADA BANGUNAN BUNYI YANG TERKENA PADA PERMUKAAN YANG

PADAT,IA AKAN TERMAMPAT KE PERMUKAAN TERSEBUT.

SEBABNYA SEMUA PERMUKAAN TIDAK MAMPU MENYERAP SEMUA GELOMBANG BUNYI.

OLEH ITU,PEMBALIKAN BERTENTANGAN KAN BERLAKU.

BANGUNAN YANG DIBINA DI KAWASAN LALULINTAS AKAN TERDEDAH DENGAN PENGHASILAN BUNYI YANG TINGGI.

SELAIN ITU,ENJIN,KUASA ENJIN,TAYAR,SISTEM PENYEJUKAN DAN EKZOS JUGA PENGARUHI BUNYI BISING LALU LINTAS YANG TERHASIL DARIPADA KENDERAAN.

HINGAR KAPAL TERBANG

Kapal terbang yang berlepas dari kawasan lapangan akan mengeluarkan hingar yang teruk berpunca dari enjin kapal terbang.

Kawasan di sekitar lapangan terbang akan mendapat kesan hingar yang teruk.

Contoh keadaan ini di Malaysia adalah di kawasan Lapangan Antarabangsa Subang Jaya.

Penduduk di sekitar kawasan lapangan terbang akan mengalami kehilangan pendengaran sementara akibat dari aktiviti pelepasan kapal terbang.

PENGENALAN

HINGAR KAPAL TERBANG

kekerapan pesawat berlepas. kelajuan enjin pesawat ketinggian pesawat terbang. waktu penerbangan.

FAKTOR MEMPENGARUHI HINGAR KAPAL TERBANG

Air Transportation Noise

Air transportation accounts for 20% of total noise emissions by transportation. As air transportation took a growing importance in inter-city transportation and that jet engines were predominantly used, noise emissions have increased significantly to the point of becoming a major concern near airports.

Noise comes from the jet engine, the aerodynamic friction and ground craft operations. Even if the turbofan is the least noisy jet propulsion technology available, aircrafts are an acute source of noise in several urban areas. Noise from aircraft operation is known to have direct impact on property values around airports. This effect is distributed along major approach and take off lanes.

The establishment of heavily used flight paths between major cities creates noise corridors where ambient noise is almost prevalent. This is particularly noted when those corridors are over densely populated areas.

AIR TRAFFIC NOISE(AEROPLANE)

GARPH FOR GARPH FOR AN AEROPLANE AN AEROPLANE NOISENOISE

DIAGRAM AN AEROPLANE NOISE

Rail Transportation Noise Rail accounts for 10% of total noise emissions by

transportation. Noise comes from the engine (mostly diesel), the friction of wheels over the rails, and whistle blowing. Furthermore, when trains are moving at high speed, aeroacoustic (a branch of acoustics that studies noise generation via either turbulent fluid motion or aerodynamic forces interacting with surfaces) noise becomes more important than other sources. Depending of the train aerodynamics, noise emissions are from 50 to 80 times the logarithm of train speed and become significant at speeds higher than 200 km/hr.

When rail / truck transshipment is involved, the convergence of trucks towards rail yards provides an additional source of noise related to rail transportation activities.

Around 3% of the population may be exposed to high noise levels from rail transportation in OECD countries. The level of exposure is obviously related to the importance and location of rail transportation infrastructure. The most important noise impacts of rail operations are in urban areas where the majority transshipment functions are performed. Furthermore, rail terminals are often located in the central and high density areas of cities.

DOMESTIC NOISE Noise from neighbors is often one of the

main causes of noise complaints. These complaints are largely due to the inconsiderate or thoughtless use of powered domestic appliances (vacuum cleaners, washing machines, lawn mowers, etc.), systems for music reproduction, TV sets, or hobby activities. Substantial societal problems, more infrequent but nonetheless important, are caused by disturbing noise emanating from neighbors and their social activities.

JIRAN

MUZIK

DIY (UBAHSUAI)

ALAT PENGGERA

HAIWAN PELIHARAAN (ANJING)

BUNGA API

NOISE FROM LEISURE ACTIVITIES The possibilities of using powered machines

in leisure activities are increasing all the time.

For example, motor racing, off-road vehicles, motorboats, water skiing, snowmobile

Shooting activities not only have considerable potential for disturbing nearby residents, but can also damage the hearing of those taking part.

Discotheques and rock concerts may exceed hearing damage risk criteria for the musicians, employees and the audience.

HOUSEHOLD EQUIPMENT The household equipments are amongst the

minor contributors to noise pollution. These machines include mixers, vacuum

cleaners and other noise creating equipments. The effects of noise pollution caused by these

machines shouldn't be neglected. This is because one has to work in close

contact with the equipments and the magnitude of sound that one need to bear is high.

Ceremonies, Festivals and Entertainment Events In many countries, there are regular ceremonies,

festivals and entertainment events to celebrate life periods. Such events typically produce loud sounds, including music and impulsive sounds.

There is widespread concern about the effect of loud music and impulsive sounds on young people who frequently attend concerts, discotheques, video arcades, cinemas, amusement parks and spectator events.

At these events, the sound level typically exceeds 100 dB. Such noise exposure could lead to significant hearing impairment after frequent attendances

OTHERS CAUSEThe boilers, plumbing equipment, air

conditioners, generators and fans contribute to noise pollution to some extent.

Noise created by people in public places too is a major contributor amongst different sources.

Loudspeakers used in public places are responsible for creating noise of a high degree/amplitude.