Pencemaran udaraDaripada Wikipedia, ensiklopedia bebas.

Pemandangan dari Bukit Hollywood, jerebu menjejaskan penglihatan bandar Los Angeles pada waktu siang.

Pencemaran udara merupakan satu keadaan yang melibatkan pengenalan sebarang bahan kimia, jirim

zarahan atau bahan biologi yang boleh menyebabkan mudarat, ketidakselesaan kepada manusia atau

organisma hidup lain serta merosakkan alam sekitar apabila ia dibebaskan ke atmosfera. Contoh pencemar

udara adalah seperti gas karbon dioksida, sulfur dioksida, kloroflorokarbon, bau-bauan, logam toksik

seperti plumbum dan tembaga dan sisa radioaktif.

Pencemaran udara berpunca daripada pelepasan asap kotor oleh industri terus ke udara melalui

cerobong asap kilang, kenderaan motor di jalan raya dan letusan gunung berapi. Antara kesan pencemaran

udara adalah penipisan lapisan ozon, jerebu, hujan asid dan pemanasan bumi. Pencemaran udara

mungkin boleh memberi kesan terhadap kesihatan, keselamatan dan keselesaan manusia ataupun harta

benda.

Pembebasan asap yang mengandungisulfur dioksida ke udara

Isi kandungan

  [sorokkan]

1 Klasifikasi pencemaran udara

o 1.1 Pencemaran primer

o 1.2 Pencemaran sekunder

2 Kesan

o 2.1 Kesihatan manusia

o 2.2 Tumbuhan

o 2.3 Haiwan

o 2.4 Bahan

o 2.5 Penyusutan lapisan ozon

o 2.6 Hujan asid

o 2.7 Kesan rumah hijau dan pemanasan global

o 2.8 Atmosfera

3 Lihat juga

[sunting]Klasifikasi pencemaran udara

Pencemaran udara diklasifikasikan kepada dua bahagian iaitu pencemaran primer dan pencemaran

sekunder.

[sunting]Pencemaran primer

Pencemaran primer ialah pencemaran yang dihasilkan sulfur monoksida dan karbon monoksida hasil

daripada pembakaran tidak lengkap. Ia menyebabkan zarah-zarah halus terampai di udara.

Kebanyakan pencemaran udara primer ini dilepaskan melalui ekzos kenderaan, kawasan industri yang

melepaskan asap atau bahan pencemar, dan penggunaan dapur arang kayu yang tidak terkawal

[sunting]Pencemaran sekunder

Pencemaran udara sekunder adalah berpunca hasil daripada tindak balas sulfur dioksida yang bergabung

dengan wap-wap air di udara.

[sunting]Kesan

[sunting]Kesihatan manusia

Kesan utama pencemaran udara kepada manusia adalah sistem pernafasan. Gas-gas seperti karbon

monoksida akan meracuni sistem pengangkutan oksigen dalam darah dan melambatkan tindak balas

manusia. Kesan seterusnya akan menyebabkan seseorang itu mengantuk, mempunyai penyakit lelah dan

mengurangkan fungsi paru-paru.

Bahan tercemar seperti nitrogen oksida boleh menyebabkan edema dan pendarahan pulmonari. Bahan

tercemar seperti gas ozon boleh menimbulkan kerengsaan dan akan menyebabkan inflamasi paru-paru

dan ketidakupayaan untuk bergerak. Habuk, asap, kabus, wap atau bahan-bahan lain juga menghalang

penglihatan mata manusia.

Kajian Pertubuhan Kesihatan Sedunia (WHO) telah menyatakan sebanyak 3.3 juta manusia mati setiap

tahun disebabkan oleh pencemaran udara. Ia adalah tiga kali lebih tinggi daripada jumlah kematian yang

disebabkan oleh kemalangan kenderaan.

[sunting]Tumbuhan

Kesan kepada tumbuhan adalah seperti mengalami kerosakan nekrosis (keguguran daun), klorosis

(pertukaran warna), dan pertumbuhan terbantut.

Kesan ini juga akan menyebabkan sebahagian daripada penduduk bumi kekurangan sumber makanan dan

ekonomi yang akhirnya menganggu kehidupan seharian. Selain itu, kesan ini akan mengganggu

keseimbangan ekosistem.

[sunting]Haiwan

Haiwan akan terancam atau mati akibat daripada pencemaran udara. Perkara ini disebabkan oleh udara

yang memasuki paru-paru haiwan. Selain itu, makanan daripada sumber tumbuhan akan tercemar oleh

pencemaran udara.

[sunting]Bahan

Kesan kepada bahan bermaksud kerosakan berlaku akibat daripada pencemaran udara seperti kekotoran

pada pakaian, pencemaran pada permukaan dinding bangunan dan sebagainya. Perkara ini berlaku akibat

daripada pengenapan asap atau zarah halus.

Hakisan logam juga merupakan kesan daripada pencemaran udara akibat kehadiran sulfur dioksida di

dalam udara.

[sunting]Penyusutan lapisan ozon

Pencemaran udara akan menyebabkan berlakunya pemanasan global akibat daripada penyusutan lapisan

ozon yang melindungi bumi daripada sinaran terus cahaya matahari. Pendedahan secara terus kepada

cahaya matahari boleh menyebabkan kanser kulit. Di samping itu, pancaran matahari yang terik juga akan

menyebabkan berlakunya pencairan ais di bahagian kutub bumi. Pada masa kini, ekosistem di dunia

mengalami ketidakseimbangan.

[sunting]Hujan asid

Rencana utama: hujan asid

Hujan asid berlaku disebabkan oleh penggabungan gas sulfur dioksida dan nitrogen oksida dengan

air hujan dan seterusnya menjadi asid sulfurik dan asid nitrik. Asid ini akan terkumpul di dalam awan

dan bergerak ke tempat-tempat lain. Asid tersebut akan turun bersama-sama dengan hujan dan

menimpa hidupan yang terdapat di dunia. Kesannya, ia membunuh tumbuh-tumbuhan dan

juga hidupan air. Tambahan pula, ia juga boleh menghakis pakaian, kertas dan bahan binaan

bangunan. Selain itu, asid tersebut juga meresap ke dalam tanah dan menyebabkan kualiti tanah

berkurang serta tidak subur.

[sunting]Kesan rumah hijau dan pemanasan global

Rencana utama: kesan rumah hijau dan pemanasan global

Kesan yang paling ketara dan sedang hangat diperbincangkan oleh seluruh negara pada masa

kini adalah tentang kesan pemanasan global yang disebabkan oleh kesan rumah hijau.

Kenaikan suhu bumi dan penipisan lapisan ozon juga menjadi punca kepada pemanasan global

yang dapat dirasakan oleh seluruh dunia. Kenaikan suhu bumi adalah disebabkan oleh

pembebasan gas-gas karbon dioksida yang terkumpul di dalam udara.

Gas karbon dioksida yang terlalu banyak telah menyebabkan haba di bumi terperangkap dan

akhirnya suhu bumi meningkat dan persekitarannya menjadi panas. Penyusutan lapisan ozon juga

menyebabkan kejadian pemanasan global ini. Kesannya adalah permukaan bumi akan menjadi

panas, ekosistem terganggu, banjir berlaku secara kerap dan juga berlakunya kejadian alam yang

tidak normal.

[sunting]Atmosfera

Kesan terhadap atmosfera yang dibawa oleh pencemaran udara pula ialah mengurangkan jarak

penglihatan akibat jerebu.

Pemanasan global berkaitan dengan peningkatan suhu dunia. Suhu bumi telah meningkat dua

darjah dan kadarnya berbeza mengikut benua dan kawasan tertentu. Kajian mendapati

kawasan Artik lebih pantas menjadi panas berbanding kawasan lain. Perubahan iklim biasanya

berlaku dalam tempoh 10,000 tahun tetapi kini perubahan iklim berubah dalam tempoh 100 tahun

sahaja, jarak hanya 2 generasi sahaja.

Suhu bumi meningkat sejak tahun-tahun 90an. Kajian mendapati iklim panas melampau di Perancis,

iklim lebih panas di rantau Siberia dan pencairan "permafrost" (lapisan tanah yang kekal beku di

rantau paling sejuk) terutamanya di rantau Artik. Ahli sains meramalkan keseluruhan ais laut di Artik

akan cair pada musim panas 2099. Litupan ais Greenland dan Antartika Barat akan mencair . Paras

laut akan meningkat kira-kira 7 meter secara mendadak.

Isi kandungan

  [sorokkan]

1 Faktor pemanasan global

2 Pelepasan karbon dioksida

3 Kesan pemanasan global di Malaysia

4 Tenaga alternatif

5 Rujukan

[sunting]Faktor pemanasan global

Panel Antara Kerajaan tentang Perubahan Cuaca (IPCC) ditubuhkan pada 1988 oleh Pertubuhan

Meteorologi Sedunia serta Program Alam Sekitar Pertubuhan Bangsa-Bangsa Bersatu (PBB).

Kegiatan terasnya adalah menyemak dan menilai maklumat saintifik, teknikal dan sosio-ekonomi yang

terkini. Saintis alam sekitar telah ditempatkan dipelbagai lokasi strategik dan mengumpulkan laporan

ilkim dan cuaca seluruh dunia secara sistermatik. Dapatan daripada kajian ini amat memeranjatkan

terutama berhubung tentang faktor pemanasan global dan kesan jangka pendek dan panjang

daripadanya.

Laporan 1 (1990) dan Laporan 2 (1995) IPCC menunjukkan banyak ketidakpastian iklim dunia

dan bersifat negatif . Pemanasan global ini akan menjejaskan manusia atau tamadunnya.

Laporan ketiga (2001) berkisar kepada "Menangani Perubahan Iklim.

Laporan Penilaian Keempat tentang (Perubahan Iklim 2007) .

Kajian mendapati 98 % punca pemanasan global ialah pelepasan karbon dioksida akibat pembakaran

bahan bakar fosil yang telah dilakukan sejak abad ke-18. . Perubahan penggunaan tanah

menyumbang 30 peratus pelepasan karbon dioksida. Kesan rumah hijau lebih hebat dan iklim dunia

akan berubah secara mendadak, tanpa dapat dibendung lagi.

[sunting]Pelepasan karbon dioksida

Impak pelepasan karbon dioksida tidak difahami ramai kerana gas tersebut tidak berbau dan

bukan toksik.Konsentrasi karbon dioksida di atmosfera telah meningkat daripada kira-kira 280

bahagian sejuta (ppm) dicatat di kurun ke-18 (sebelum era revolusi perindustrian) kepada 379 ppm

pada tahun 2005.

Menjelang 2099 kadarnya meningkat kepada 700 ppm jika cara hidup sekarang berterusan. Secara

bandingan , planet lain seperti Marikh, suhunya kira-kira 400 darjah celcius dan 90 peratus daripada

atmosferanya adalah karbon dioksida. Hampir tiada kehidupan di Marikh dan bumi akan menjadi

seperti itu.

IPCC mendesak seluruh kerajaan dan penduduk dunia menstabilkan tahap karbon dioksida di

atmosfera kepada paras yang boleh diuruskan iaitu 450 ppm. Bagi menghapuskan kepekatan karbon

dioksida di dalam atmosfera, ia mengambil masa antara 200 atau 300 tahun . Walau apapun tindakan

pemulihan dilakukan , untuk kembali pulih amat sedikit.

Mulai abad ke-18 majoriti warga dunia menggunakan bahan bakar fosil daripada sumber asas air atau

kayu . Dunia ada banyak alternatif tetapi kita tidak menggunakannya secara bijak , berkesan dan

menyeluruh. Kita terlalu bergantung kepada bahan bakar fosil. Negara

membangun seperti India dan China tidak setuju dengan pengurangan pengggunaan bahan bakar

fosil. 2 bilion penduduk di India dan China menggunakan bahan bakar fosil secara keterlaluan.

[sunting]Kesan pemanasan global di Malaysia

Sumber ekosistem yang ada telah digunakan ke paras maksimum dengan penangkapan ikan

berlebihan dan pemupusan kawasan besar hutan. Enam bilion penduduk dunia kini menggunakan

sumber asli bumi secara berlebihan dan tidak terkawal . Jika pemanasan global berterusan , manusia

dan tamdunnya akan pupus sebagaimana pupusnya dinosaur.

Ramalan saintis menunjukkan peningkatan 7.0 meter paras laut, kawasan rendah seperti Kuala

Muda (Kedah) dan Kelantan akan ditenggelami air. Keadaan monsun akan bertukar sama sekali

kerana kita akan menerima lebih banyak hujan sewaktu monsun timur laut, yang bermakna lebih

banyak kejadian banjir.

Kesedaran rakyat Malaysia dan amnya masyarakat dunia sukar ditingkatkan. Hanya 3 /10 rakyat

Malaysia yang prihatin kepada isu-isu alam sekitar. Kejadian gempa bumi 26 Disember 2004 dan

banjir besar di Johor adalah pengajaran terbaik. Mendidik bukanlah untuk membuat mereka cemas

tetapi meminta mereka bertindak secara betul dan tepat.

[sunting]Tenaga alternatif

Tenaga alternatif seperti tenaga nuklear dan suria sebagai alternatif yang berdaya maju. Malaysia

perlu meneroka dan mempelajari sendiri tenaga nuklear sebagaimana Korea dan Jepun. Malaysia

menerima 300 hingga 400 watt satu meter persegi cahaya matahari..

BEIJING: Outdoor air pollution contributed to 1.2 million premature deaths in China in 2010, nearly 40 per cent of the global total, according to a new summary of data from a scientific study on leading causes of death worldwide. 

Figured another way, the researchers said, China's toll from pollution was the loss of 25 million healthy years of life from the population. 

The data on which the analysis is based was first presented in the ambitious 2010 Global Burden of Disease Study, which was published in December in The Lancet, a British medical journal. The authors decided to break out numbers for specific countries and present the findings at international conferences. The China statistics were offered at a forum in Beijing on Sunday. 

"We have been rolling out the India- and China-specific numbers, as they speak more directly to national leaders than regional numbers," said Robert O'Keefe, the vice president of the Health Effects Institute, a research organization that is helping to present the study. The organization is partly financed by the United States Environmental Protection Agency and the global motor vehicle industry. 

What the researchers called "ambient particulate matter pollution" was the fourth-leading risk factor for deaths in China in 2010, behind dietary risks, high blood pressure and smoking. Air pollution ranked seventh on the worldwide list of risk factors, contributing to 3.2 million deaths in 2010. 

By comparison with China, India, which also has densely populated cities grappling with similar levels of pollution, had 620,000 premature deaths in 2010 because of outdoor air pollution, the study found. That was deemed to be the sixth most common killer in South Asia. 

The study was led by an institute at the University of Washington and several partner universities and institutions, including the World Health Organization. 

Calculations of premature deaths because of outdoor air pollution are politically threatening in the eyes of some Chinese officials. According to news reports, Chinese officials cut out sections of a 2007 report called "Cost of Pollution in China" that discussed premature deaths. The report's authors had concluded that 350,000 to 400,000 people die prematurely in China each year because of outdoor air pollution. The study was done by the World Bank in cooperation with the Chinese State Environmental Protection Administration, the precursor to the Ministry of Environmental Protection. 

There have been other estimates of premature deaths because of air pollution. In 2011, the World Health Organization estimated that there were 1.3 million premature deaths in cities worldwide because of outdoor air pollution. 

Last month, the Organization for Economic Cooperation and Development, based in Paris, warned that "urban air pollution is set to become the top environmental cause of mortality worldwide by 2050, ahead of dirty water and lack of sanitation." It estimated that up to 3.6 million people could end up dying prematurely from air pollution each year, mostly in China and India. 

There has been growing outrage in Chinese cities over what many say are untenable levels of air pollution. Cities across the north hit record levels in January, and official Chinese newspapers ran front-page articles on the surge — what some foreigners call the "airpocalypse" — despite earlier limits on such discussion by propaganda officials. 

In February, the State Council, China's cabinet, announced a timeline for introducing new fuel standards, but state-owned oil and power companies are known to block or ignore environmental policies to save on costs. 

A study released on Thursday said the growth rate of disclosure of pollution information in 113 Chinese cities had slowed. The groups doing the study, the Institute of Public and Environmental Affairs, based in Beijing, and the Natural Resources Defense Council, based in Washington, said that "faced with the current situation of severe air, water and soil pollution, we must make changes to pollution source information disclosure so that information is no longer patchy, out of date and difficult to obtain." 

Chinese officials have made some progress in disclosing crucial air pollution statistics. Official news reports have said 74 cities are now required to release data on levels of particulate matter 2.5 micrometers in diameter or smaller, which penetrate the body's tissues most deeply. For years, Chinese officials had been collecting the data but refusing to release it, until they came under pressure from Chinese who saw that the United States Embassy in Beijing was measuring the levels hourly and posting the data in a Twitter feed, @BeijingAir. 

Last week, an official Chinese news report said the cost of environmental degradation in China was about $230 billion in 2010, or 3.5 per cent of the gross domestic product. The estimate, said to be partial, came from a research institute under the Ministry of Environmental Protection, and was three times the amount in 2004, in local currency terms. It was unclear to

what extent those numbers took into account the costs of health care and premature deaths because of pollution

Pencemaran airDaripada Wikipedia, ensiklopedia bebas.

Pencemaran sungai

Pencemaran air ialah pencemaran yang berlaku di sungai, tasik dan laut. Lokasi berair sering disalah

anggap sebagai tempat pembuangan sampah terutama daripada aktiviti manusia.

[sunting]Pencemaran Air di Malaysia

Punca utama pencemaran air di Malaysia adalah seperti pembuangan sampah dari kawasan perumahan di

sepanjang sungai, tepi tasik dan laut. Penduduk membuang najis manusia dan najis binatang ternakan

seperti ayam, babi, lembu dan lain-lain ke dalam sungai. Sebagai contoh, Sungai Semenyih pernah

dicemari dengan puluhan ladang babi pada tahun 1980-an.

Kilang memproses getah dan minyak kelapa sawit juga menjadi punca kepada pencemaran air sepanjang

sungai di Malaysia. Sisa toksik dibuang dan dialirkan ke dalam longkang, parit, terusan dan seterusnya ke

dalam sungai. Pemandangan dari udara yang bertempat di Sungai Juru yang terletak diSeberang

Perai, Pulau Pinang telah menunjukkan warna air yang berwarna hitam pekat apabila sampai ke laut.

Para petani yang bekerja di Tanah Tinggi Cameron telah mengamalkan penggunaan baja kimia dan racun

serangga sehingga menjejaskan kualiti air minuman di Sungai Terla. Hotel dan rumah kongsi para pekerja

tidak mempunyai sistem perparitan yang sempurna sehingga menyebabkan najis manusia tidak dapat

dirawat dengan betul. Kes ini juga telah didedahkan kepada wartawan dan dipertontonkan di televisyen.

Selepas itu, barulah Majlis Daerah Cameron Highlands mengambil peranan dengan turut sama mengambil

tindakan bagi memperbetulkan keadaan.

Pengilang dari Taiwan telah dilaporkan mengeksport sisa kimia ke Malaysia dan ditanam di kawasan

terpencil di Johor, Malaysia. Beberapa negara maju juga membuang sisa radioaktif dengan memasukkan

sisa ini ke dalam tong-tong dram sebelum membuangnya ke dalam laut. Tindakan ini boleh merosakkan

hidupan laut. Longgokan tayar buruk di dasar laut terutamanya di Laut China Selatan telah digunakan

sebagai tempat ikan berlindung dan membiak di dasar laut. Sesetengah pulau tidak mempunyai sistem

pelupusan sampah. Oleh itu, telah wujud istilah ‘pulau sampah’ secara terancang atau tidak terancang.

Noise pollution is displeasing or excessive noise that may disrupt the activity or balance of human or

animal life. The word noise is cognate with the Latin wordnauseas, which means disgust or discomfort.[1] The source of most outdoor noise worldwide is mainly caused by machines and transportation

systems, motor vehicles, aircrafts, and trains.[2][3] Outdoor noise is summarized by the

word environmental noise. Poor urban planning may give rise to noise pollution, since side-by-side

industrial and residential buildings can result in noise pollution in the residential areas.

Indoor noise is caused by machines, building activities, music performances, and especially in some

workplaces. There is no great difference whether noise-induced hearing loss is brought about by

outside (i.e. trains) or inside (i.e. music) noise.

High noise levels can contribute to cardiovascular effects in humans, a rise in blood pressure, and an

increase in stress and vasoconstriction, and an increased incidence of coronary artery disease. In

animals, noise can increase the risk of death by altering predator or prey detection and avoidance,

interfere with reproduction and navigation, and contribute to permanent hearing loss.

Contents

  [hide]

1   Health

o 1.1   Human

o 1.2   Wildlife

2   Impact in the United Kingdom

3   Mitigation

4   Legal status

5   References

6   External links

[edit]Health

[edit]Human

Loud music such as in a discothèque can be a risk for human health

Main article: Health effects from noise

Noise pollution affects both health and behavior. Unwanted sound (noise) can damage psychological

health. Noise pollution can cause annoyance and aggression,hypertension, high stress levels, tinnitus,

hearing loss, sleep disturbances, and other harmful effects.[4][5][6][7] Furthermore, stress and

hypertension are the leading causes to health problems.[5][8]

Chronic exposure to noise may cause noise-induced hearing loss. Older males exposed to

significant occupational noise demonstrate significantly reduced hearing sensitivity than their non-

exposed peers, though differences in hearing sensitivity decrease with time and the two groups are

indistinguishable by age 79.[9] A comparison of Maaban tribesmen, who were insignificantly exposed to

transportation or industrial noise, to a typical U.S. population showed that chronic exposure to

moderately high levels of environmental noise contributes to hearing loss.[4]

High noise levels can contribute to cardiovascular effects and exposure to moderately high levels

during a single eight-hour period causes a statistical rise in blood pressure of five to ten points and an

increase in stress,[4] and vasoconstriction leading to the increased blood pressure noted above, as well

as to increased incidence of coronary artery disease.

Noise pollution also is a cause of annoyance. A 2005 study by Spanish researchers found that in

urban areas households are willing to pay approximately four Euros per decibel per year for noise

reduction.[10]

[edit]Wildlife

Noise can have a detrimental effect on wild animals, increasing the risk of death by changing the

delicate balance in predator or prey detection and avoidance, and interfering the use of the sounds in

communication, especially in relation to reproduction and in navigation. Acoustic overexposure can

lead to temporary or permanent loss of hearing. [11]

An impact of noise on wild animal life is the reduction of usable habitat that noisy areas may cause,

which in the case of endangered species may be part of the path to extinction. Noise pollution has

caused the death of certain species of whales that beached themselves after being exposed to the

loud sound of military sonar,[12] (see also Marine mammals and sonar).

Noise also makes species communicate more loudly, which is called Lombard vocal response.[13] Scientists and researchers have conducted experiments that show whales' song length is longer

when submarine-detectors are on.[14] If creatures do not "speak" loudly enough, their voice will

be masked by anthropogenic sounds. These unheard voices might be warnings, finding of prey, or

preparations of net-bubbling. When one species begins speaking more loudly, it will mask other

species' voice, causing the whole ecosystem eventually to speak more loudly.

European Robins living in urban environments are more likely to sing at night in places with high levels

of noise pollution during the day, suggesting that they sing at night because it is quieter, and their

message can propagate through the environment more clearly.[15] The same study showed that

daytime noise was a stronger predictor of nocturnal singing than night-time light pollution, to which the

phenomenon often is attributed.

Zebra finches become less faithful to their partners when exposed to traffic noise. This could alter a

population's evolutionary trajectory by selecting traits, sapping resources normally devoted to other

activities and thus leading to profound genetic and evolutionary consequences.[16]

[edit]Impact in the United Kingdom

Figures compiled by Rockwool, the mineral wool insulation manufacturer, based on responses from

local authorities to a Freedom of Information Act (FOI) request reveal in the period April 2008 –

2009 UK councils received 315,838 complaints about noise pollution from private residences. This

resulted in environmental health officers across the UK serving 8,069 noise abatement notices, or

citations under the terms of the Anti-Social Behaviour (Scotland) Act. In the last 12 months, 524

confiscations of equipment have been authorised involving the removal of powerful speakers, stereos

and televisions. Westminster City Council has received more complaints per head of population than

any other district in the UK with 9,814 grievances about noise, which equates to 42.32 complaints per

thousand residents. Eight of the top 10 councils ranked by complaints per 1,000 residents are located

in London.[17]

[edit]Mitigation

The sound tube in Melbourne, Australia is designed to reduce roadway noise without distracting from the area's

aesthetics

Ear muffs for human protection against noise pollution

Main article: Noise mitigation

Roadway noise can be reduced by the use of noise barriers, limitation of vehicle speeds, alteration of

roadway surface texture, limitation of heavy vehicles, use of traffic controls that smooth vehicle flow to

reduce braking and acceleration, and tire design. An important factor in applying these strategies is

a computer model forroadway noise, that is capable of addressing local topography, meteorology,

traffic operations, and hypothetical mitigation. Costs of building-in mitigation can be modest, provided

these solutions are sought in the planning stage of a roadway project.

Aircraft noise can be reduced by using quieter jet engines. Altering flight paths and time of day runway

has benefitted residents near airports.

Industrial noise has been addressed since the 1930s via redesign of industrial equipment, shock

mounted assemblies and physical barriers in the workplace.

[edit]Legal status

Main article: Noise regulation

Up until the 1970s governments viewed noise as a "nuisance" rather than an environmental problem.

In the United States, there are federal standards for highway and aircraft noise; states and local

governments typically have very specific statutes on building codes, urban planning, and roadway

development.

Noise laws and ordinances vary widely among municipalities and indeed do not even exist in some

cities. An ordinance may contain a general prohibition against making noise that is a nuisance, or it

may set out specific guidelines for the level of noise allowable at certain times of the day and for

certain activities.

Portland, Oregon instituted the first comprehensive noise code in 1975 with funding from

the EPA (Environmental Protection Agency) and HUD (Housing and Urban Development). The

Portland Noise Code includes potential fines of up to $5000 per infraction and is the basis for other

major U.S. and Canadian city noise ordinances.[18]

Many conflicts over noise pollution are handled by negotiation between the emitter and the receiver.

Escalation procedures vary by country, and may include action in conjunction with local authorities, in

particular the police.

Noise pollution is a major problem in countries such as India during the festivals of Diwali, Navaratri,

and Ganpati. The government of India has regulations against firecrackers and loudspeakers, but

enforcement is extremely lax.[19] Awaaz Foundation is an Indian NGO working to control noise pollution

from various sources in Mumbai through advocacy, public interest litigation, awareness, and

educational campaigns since 2003