gangguan pendengaran adalah:

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Kebisingan Industri

Penyebab kehilangan/gangguan pendengaran adalah:  Kebisingan industri  Luka pada telinga akibat ledakan, shock pukulan pada kepala dan benda asing atau infeksi pada telinga.

Inside NOISE

What is noise?

What is noise?

Definisi:  Suara-suara yang tidak dikehendaki (for Who? Why?)  Suara: sensasi yang diterima telinga sebagai akibat fluktuasi tekanan udara terhadap tekanan udara d yang stabil. t bil  Telinga akan merespons fluktuasi-fluktuasi kecil tersebut dengan sensitivitas yang sangat besar.  Bising juga diartikan vibrasi/energy yang dikonduksikan dalam media udara, cairan, padatan, tidak tampak dan dapat memasuki telinga serta menimbulkan sensasi pada alat dengar

– Definition, energy conducted and sensed, properties: intensity/pressure, frequency, exposure,

Why unwanted? – Health Effect, age, psychological: annoyed, concentration, rest/relax problem, communication annoyance, physiological: blood, heart, hearing loss, nausea, muscle control, acoustic trauma (permanent) vs temporary,

Who are susceptible? – Esp. Industrial workers, determining factors: sensitivity, age,

How to evaluate & control?

Jenis Bising

Properties of noise?

 Tergantung pada durasi dan frekuensi  Steady wide band noise, bising yang meliputi suatu jelajah frekuensi yang lebar (bising dalam ruang mesin)  Steady narrow band noise, bising dari sebagian besar energi bunyi yang terpusat pada beberapa frekuensi saja, contoh h gergajiji bundar. b d  Impact noise, kejutan singkat berulang, contoh riveting  Intermitten noise, bising terputus, contoh lalu lintas pesawat

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Karakteristik bising

Contoh…

1.

Intensitas/tekanan (sound pressure/intensity) 2. Frekuensi 3. Durasi eksposur terhadap bising Ketiga g karakteristik diperlukan p karena:  Semakin keras suara, semakin tinggi intensitasnya  Frekuensi tinggi lebih berbahaya terhadap kemampuan dengar. Telinga manusia lebih sensitif terhadap frekuensi tinggi  Semakin lama durasi eksposur semakin besar kerusakan pada mekanisme pendengaran

Intensitas  Laju aliran energi tiap satuan luas yang dinyatakan dalam desibell (dB) – Alexander Graham Bell dB adalah merupakan satuan yang dihasilkan dari perhitungan yang membandingkan suatu tekanan suara yang terukur terhadap suatu tekanan acuan (sebesar 0,0002 dyne/cm2).  B = log (int.terukur/int.acuan) untuk mendapatkan angka yang lebih akurat ditentukan dengan angka kelipatan 10 (desi)  Intensity level dB=10 Log (IT/IA)  Sound pressure level (tekanan bunyi) = 20 log (IT/IA), karena intensitas sebanding dengan kuadrat tekanan bunyi.

Tekanan = Sound Pressure  Manusia dapar mendengar suara pada tekanan antara 0,0002 dynes/cm2 (ambang dengar/threshold of hearing) sampai 2000 dynes/cm2  range besar sehingga satuan yang dipakai dB (decibel): logaritmik  Dinyatakan dalam decibel (dB) yang dilengkapi skala A, B, dan C  sesuai dengan berbagai kegunaan  Skala A digunakan karena merupakan response yang paling cocok dengan telinga manusia (peka terhadap frekuensi tinggi)  Skala B dan C untuk evaluasi kebisingan mesin, dan cocok untuk kebisingan frekuensi rendah

The decibel SOUND INTENSITY SOUND SOURCE

     

Ruang kelas: ?dB Rumah Restauran Berbisik Berteriak Jet plane



Lowest limit of hearing

LINEAR UNITS Bel 1

LOGARITHMIC UNITS Decibel 0

0

Rustling leaf

10

1

10

Quiet farm setting

100

2

20

Whisper (5 feet)

1,000

3

30

Dripping faucet, quite office

10,000

4

40 50

Low conversation, residence

100,000

5

Ordinary conversation

1,000,000

6

60

Idling car

10,000,000

7

70

Silenced compressor, very noisy restaurant

100,000,000

8

80

Backhoe

1,000,000,000

9

90

Unsilenced compressor

10,000,000,000

10

100

Rock dril, woodworking

100,000,000,000

11

110

Pile driver*

1,000,000,000,000

12

120

Rivet gun*

10,000,000,000,000

13

130

Explosive-actuated tool*, jet plane

100,000,000,000,000

14

140

*Intermittent or "impulse" sound Source: Construction Safety Association of Ontario, Hearing Protection for the Construction Industry, 1985, page 3

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The decibel  dB = 10 log10 (I1/I0) dB = 20 log10 (P1/P0)

I = Intensitas P= Tekanan = 0,0002

dynes/cm2 SP (microbar) 0,0002 0,002

SPL (dB) 0 20

Ratio Intensitas 100 102

Pressure Sound intensities Pa Bel (B) Decibel (dB) Threshold of hearing 0,00002 0 0 Quiet office 0,002 4 40 Ringing alarm clock at 1 m 02 0,2 8 80 Ship's engine room 20 12 120 Turbo jet engine 2000 16 160

Jadi bila SP berubah 10x, maka dB bertambah ? x

 Pneumatic chip hammer

103-113

Crane

90-96

Jackhammer

102-111

Hammer

87-95

Concrete jjoint cutter

99 102 99-102

Gradeall

87 94 87-94

Skilsaw

88-102

Front-end loader

86-94

Stud welder

101

Backhoe

84-93

Bulldozer

93-96

Garbage disposal (at 3 ft.)

80

Earth Tamper

90-96

Vacuum cleaner

70

Satuan (Konversi)

Sumber > 1…..

1bar=105Pa=105N/m2  =105.105dyne/104cm2  =106dyne/cm2 atau 1microbar = 1 dyne/cm / 2

dB=L=20 log(P1/P2)=10 log(P1/P2)2 L/10= log(P1/P2)2 10L/10= 10log(P1/P2)^2=(P1/P2)2 L=10 log(P1/P2)2  =10 log 10L/10 (satu sumber)  =10 log (Σ10Li/10)  L =10 log (10L1/10+ 10L2/10+…)

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Sumber > 1….. (Contoh) (banyak sumber)

 =10 log (10L1/10+10L2/10+…)

ΣdBA yang turun ditambah ke bunyi terbesar

0

3,0

1

2,6

2

2,1

3

1,8

4

1,5

5

1,2

6

1,0

7

0,8

8

0,6

10

0,4

12

0,3

14

0,2

16

0,1

Frekuensi Adalah jumlah getaran dalam tekanan suara per satuan waktu (Hertz atau cycle per detik), frekuensi dipengaruhi ukuran, bentuk dan p pergerakan g sumber,, pendengaran normal orang dewasa dapat menangkap bunyi dengan frekuensi 2015.000 Hz.

Why unwanted? Health Effect, age, psychological: annoyed, concentration, rest/relax problem, communication annoyance, physiological: blood, heart, hearing loss, nausea, muscle l control, t l acoustic ti trauma t (permanent) vs temporary,

Decibel yang ditam mbahkan pada tingkat kebisingan lebih tinggi

 =10 log (Σ10Li/10)

Kebisingan dari 2 sumber

Perbedaan antara sumber bunyi

3

Perbedaan (dB)

Tambah pada yg lebih tinggi

2,5

0 atau 1

3

2 atau 3

2

2 1,5

4–9

1

10+

0

1 0,5

2 4 6 8 10 12 14 Perbedaan antara 2 tingkat bising, dB(A)

Frekuensi  Dibagi dalam 8 octaf (octave bands), 37.5, 75, 150, 300, 600, 1200, 2400, 4800, 9600 Hz  Telinga manusia bereaksi beda terhadap berbagai frekuensi  Kebisingan ‘rata-rata’ rata-rata mencakup seluruh taraf kebisingan dari setiap frekuensi  dihitung Leq Leq = ekuivalen noise level/ekuivalen energi level Leq = 10 log10 (Σ 10 Lpi/10)

Efek bising pada manusia  Psikologis, terkejut, mengganggu dan memutuskan konsentrasi, tidur dan saat istirahat  Fisiologis, seperti menaikkan tekanan darah dan detak jantung, mengurangi ketajaman pendengaran, sakit telinga, mual, kendali otot terganggu, dll.  Gangguan komunikasi yang mempengaruhi kenyamanan kerja dan keselamatan.

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Interference with communication by speech  When background or ambient noise levels are sufficiently high enough, the background noise can mask the sound levels of speech that wish to be heard.

Mechanics of hearing 

 Restaurants can often be classic examples of excessive noise interference due to lack of sufficient quality or quantity off sound d absorbing b bi materials t i l th thatt preventt excessive i noise i buildup.  Diners have to speak louder and louder to be heard and in doing so compete with one another, thereby increasing the sound levels to even greater levels. Appropriate acoustical treatment will prevent the reflected noise buildup and significantly reduce the necessity for diners to speak louder to enjoy conversations with one another.

Mekanisme pendengaran

Mekanisme pendengaran

 Terdiri dari 3 bagian: telinga luar (daun telinga sampai membran timpani) meneruskan gelombang ke telinga tengah  Telinga tengah: membran timpani (yang melekat pada 3 tulang kecil sampai membrana ovale)  getaran diteruskan  Telinga dalam: tube berspiral seperti rumah siput berisi cairan  cairan bervibrasi  stimulasi rambut sel  impuls syaraf otak

Pemaparan pada suara tinggi dan periode/durasi yang lama akan menyebabkan sel syaraf pendengar dan rambut p pada corti over aktif sehingga gg menimbulkan kehilangan pendengaran permanen

Pengukuran efek bising

Audiometric test 

Untuk mengevaluasi akibat pemaparan terhadap kehilangan pendengaran, kenyamanan, y , interferensi komunikasi dan mengumpulkan informasi untuk pengontrolan.

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Audiometric test

Standard OSHA Current OSHA Standards  •1926.52 Occupational Noise Exposure •TABLE D-2 - PERMISSIBLE NOISE EXPOSURES



Duration per day, hours

NAB Kebisingan di lingkungan kerja USA (TLV ACGHI) t (eksposur) jam dB(A) 8 90 6 92 4 95 3 97 2 100 1,5 102 1 105 0,5 110 <0,25 115 kebisingan impulsif < 140 dB

INDONESIA Permen 51/1999 t dBA 8 85 4 88 2 91 1 94 30 mnt 97 15 mnt 100 7,5 mnt 103 3,75 mnt 106 1,88 mnt 109 dst dilarang > 140 dB

Ketulian = berkurangnya

ketajaman pendengaran dibanding/terhadap orang normal (15 dB)/ gol usia • Ada 2 macam: - permanen: karena penyakit, usia tua, obat, trauma, dan kebisingan - temporer: p akibat ekposur p bising, g, dapat p p pulih setelah istirahat beberapa saat tergantung keparahan • Ketulian temporer akan menjadi permanen bila terus terekpos bising (dari rumah, tempat umum, rekreasi, musik, industri, dll.) • Secara mekanisme: ketulian ada 2: - konduktif: peralatan konduksi suara rusak akibat trauma atau sakit - sensorinueral: akibat persyarafan pendengaran rusak

Sound Level dBA slow response

8

90

6

92

4

95

3

97

2

100

1 1/2

102

1

105

1/2

110

1/4 or less

115

How Does Excessive Noise Damage Your Ears?  Microscopic hair cells of the cochlea are exposed to intense noise over time  Hair cells become fatigued and less responsive, losing their ability to recover.  Damage becomes permanent resulting in noise-induced permanent threshold shift. g Loss  Risk of Hearing  Estimated Risk of Incurring Material Hearing Impairment as a Function of Average Daily Noise Exposure Over a 40-year Working Lifetime (source: NIOSH)  Average Exposure 90 dBA 29%  Average Exposure 85 dBA 15%  Average Exposure 80 dBA 3%

What Is The Purpose of Having a Hearing Test on a Regular Basis?  An audiometric testing program is used to track your ability to hear over time. – Baseline and annual

T Testt records d provide id the th only l data d t that th t can be b used to determine whether the program is preventing noise-induced permanent threshold shifts. It is an integral part of the hearing conservation program.  Case Study 1. Teenage Girl From the American Academy of Family Physicians website, Rabinowitz article

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FIGURE 1. Audiogram findings in the patient in case 1.

The area below the curves represents sound levels that the patient could still hear. (X = left ear; O = right ear)

Case Study 2 Factory Worker Age 55

Case Study 1 Conclusion  "Temporary threshold shift" example  Common in persons exposed to high noise  Represents p transient hair cell dysfunction  Complete recovery can occur  Repeated episodes of such shifts causes permanent threshold shifts because hair cells in the cochlea are progressively lost.

Case Study 2 Conclusion  Noise Induced Hearing Loss – Speech discrimination and social function interference – Difficulty in perceiving and differentiating consonant sounds – Sounds such as a baby y crying y g or a distant telephone p ringing, may not be heard at all.

 Tinnitus – Common symptom of noise overexposure – Further interferes with hearing acuity, sleep and concentration.

 These impairments have been associated with depression and an increased risk of accidents.

Carpenter Hearing Losses by Age

Pengukuran kebisingan • Mengukur overall level  sound level meter (satuan dBA) • Mengukur kebisingan pada setiap level frekuensi  SLM dengan frequency analyzer • Penentuan eksposur kebisingan pada pekerja  noise dosimeter (satuan dBA)

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Alat ukur

NOISE MEASUREMENT KIT

 Sound level meter, mencatat keseluruhan suara yang dihasilkan tanpa memperhatikan frekuensi yang berhubungan dengan bising totall (30-130 (30 130 d) – (20-20.000Hz) (20 20 000H )  Sound level meter dengan octave band analyzer, mengukur level bising pada berbagai batas oktaf di atas range pendengaran manusia dengan mempergunakan filter menurut oktaf yang diinginkan (narrow band analyzers untuk spektrum sempit 2-200 Hz)

PENGUKURAN PADA PEKERJA

NOISE KALIBRATOR

SOUND LEVEL METER

NOISE DOSIMETER

DOSEBADGER

Damage risk criteria

Noise control

 Variation in individual susceptibility  The total energy of the sound  The frequency distribution of the sound  Other characteristics of the noise exposure, such h as whether h th it is i continuous, intermittent, or made up of a series of impacts  The total daily time of exposure  The length of employment in the noise environment.

A source radiating sound energy A path along which the sound energy travels A receiver such as the human ear

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Pengendalian kebisingan

•Cara teknis: SUMBER

SUMBER

PATHW AY/MEDIA

PENERIMA/RECEIVER

Pengendalian dilakukan di 3 bagian: SUMBER, RUANG ANTARA sumber dan penerima/pekerja, pada PENERIMA/PEKERJA Urutan pengendalian paling efektif: • Kurangi/hilangkan sumber bising • Pengendalian pathway: jarak diperjauh dengan perisai/isolator/automatisasi • Perlindungan penerima dari bising (APD)

PATHWAY

PENERIMA

Substitusi

Absorpsi/damping

Isolasi pekerja

Insulasi sumber

Perisai

Reduksi waktu

Perpanjang jarak

APD

•Cara Cara medis: Pemeriksaan ketajaman pendengaran secara periodik Penempatan pekerja sesuai dengan kepekaan thd bising Monitor ketulian temporer •Cara manajemen: Reduksi waktu eksposur Diklat pemakaian dan pemeliharaan APD

Noise control

Noise control

Source: modification or redesigning of the source.

 Noise can be controlled at the source, along the path or at the worker. At the source, equipment may be replaced by quieter models, or less noisy work procedures can be adopted. In general, less friction and vibration mean less noise Maintenance procedures such as noise. lubrication may sometimes reduce noise by reducing friction. Equipment can sometimes be modified to reduce the amount of noise that is generated. Sound-absorbing material may be attached to the noise source. Or the frequency of the noise may be shifted to one that is less hazardous.

– –

The modification of compressed air jets for parts ejection, to reduce noise by altering the jet flow. M lti l Multiple-opening i air i ejection j ti nozzel: l less l noise i than th single-opening.

Noise control  Noise can often be controlled along the path to the worker with the use of soundabsorbing paneling on walls or ceilings, and enclosures around noisy machinery.  Controls at the worker include both administrative d i i t ti controls t l and d personall protective equipment. – Administrative controls modify how the work is carried out. – The time employees spend in noisy areas may be reduced. – Workers in noisy areas may be rotated to less noisy areas.

As the distance from the noise source increases, the pressure (or intensity) of the noise decreases faster than its sound level.

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Noise control

Insulation of the workers

Noisy operations may be conducted outside normal working hours to reduce the number of people exposed. Where noise exposures cannot be reduced by other methods, hearing protection is required. This includes ear plugs and ear muffs.

A separate noise insulated room provides effective control (up to 30 dB noise reduction).

Machine insulation

Control of noise by absorption

Machine: on floors and walls vibrate themsound radiation proper use of machine mountings insulates the machine and reduce the transmission of vibration

Travels out in all direction When encounter wallsreflected Total noise exposure within the room = direct + reflected noise Application of sound absorption material (However, limited: no effect on direct noise).

Reduction of exposure time

Personal protection against noise

Limiting the total daily exposure reduces the noise hazard. See TLV

Many operations cannot be quieted by engineering methods. Therefore  protection: ear plugs Properly worn: 25 – 40 dB protection Degree of discomfort  employee education is adequate

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Faktor-faktor yang mempengaruhi bising Tipe bising: menerus dan terputus Lokasi pekerja Waktu kerja

Steps aiming to control noise at work  Assess risks to develop a noise control plan  Reduce risks for all employees  Investigate and implement good practice for control of noise  Prioritise noise control measures  Use hearing protection for residual risks  Carry out a noise dosimetry program to check the effectiveness of noise control measures

Some simple noise control techniques  Application of damping material to chutes, hoppers, machine guards etc., can give a 5-25 dB reduction in the noise radiated  Cabin internal noise can be reduced by 10-12 dB by applying damping pads and sound barrier mats to floor and engine bulkhead  Reduce fan speed by 30% to achieve a noise reduction of 8 dB

BARRIER-BARIER ATAU PANEL

Noise control can be complex

ISOLASI PEKERJA/MESIN DI TEMPAT BISING

Engage employees in process Use noise control consultants to help solve your problems if complex

BAHAN ABSORBER

BAHAN BARRIER

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Hearing protectors  Selected for protection, user preference and work activity  Guard against over-protection — isolation can lead to under-use and safety risks  Require information, instruction, training, supervision and motivation  Will only protect if worn all the time and properly

Class and specification of hearing protectors Class

May be used up to this noise exposure level

10 to 13

1

90 dB(A)

14 tto 17

2

95 dB(A)

18 to 21

3

100 dB(A)

22 to 25

4

105 dB(A)

26 or greater

5

110 dB(A)

SLC80

The sound level conversion (SLC80 ) rating of a hearing protector, ear plugs or headset is a simple number and class rating that is derived from a test procedure as outlined in the Australian/New Zealand Standard AS/NZS 1270:2002

Ear plugs Properly fitted

Wrongly fitted

Reduction in protection provided by hearing protectors with decreased wearing time

Ear muffs Proper clamping force

Rating hearing protectors

Worn-out head band Example: Effectiveness of wearing earing an ear muff with a rating of 30 dB for an exposure time of one hour

Wear time

Effective attenuation

60 minutes

30 dB

55 minutes

11 dB

50 minutes

8 dB

45 minutes

6 dB

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Our challenge

Example….

Away from …  Noise assessment as the end point  Reliance on hearing protection Towards …  Control of noise risks through prioritised action plans  Introducing equipment with good noise and vibration characteristics – ‘Buy Quiet’

TWA untuk kebisingan: berdasarkan standar kebisingan. STANDAR KEBISING AN

dB(A)

1 T ukur

Jumlah jam

dB(A)

Jumlah jam

dB(A)

8

90

1,5

102

6

92

1,0

105

4

95

0,75

107

3

97

0,5

110

2

100

0,25

115

80

90

2 jam

T TLV

tt

TWA

0

95

97

100

 Durasi tingkat bising yang diijinkan dapat dilihat dari tabel di bawah ini:  Kebisingan yang terukur di suatu area adalah 90 dB selama 2 jjam sehari,, 97 dB selama 2 jam, dan sisa 4 jam berikutnya terdapat variasi tingkat bising secara bergantian 95 dB selama 10 menit dan 80 dB selama 10 menit.  Tentukan apakah tingkat kebisingan yang terukur masih dalam batas yang diijinkan atau tidak.

3.

Durasi per hari

Tingkat bising

8 6 4 3 2 1,5 1 ¾ ½ ¼

90 92 95 97 100 102 105 107 110 115

4 orang pekerja printer di unit percetakan dimana terdapat offset press. Masing-masing terpapar sbb:

Noise

No. of presses Average Sound operating Pressure Level (dBA)

Average daily time in operation (hours)

0

81

4.5

1

93

2.1

2

96

1.0

3

98

0.4

4 jam 2 jam 8 jam 4 jam 3 jam 4/8

2/4

= 1 < batas aman

2 T ukur

0

2 jam 2 jam 2 jam

T TLV

tt

8 jam 4 jam 3 jam

TWA

0

2/8

2/4

2/3

= 17/12 >batas aman

Berapa dosis harian yang diterimanya? dan Equivalent 8-hour Sound Pressure Level (SPL) yang dialami pekerja percetakan tersebut?

Noise

Jawab: Tmax 

8 2 ( L 90 ) / 5

i 1

Untuk SPL 81 dBA:

Tmax @ 81dBA 

8 = 27.858 jam 2(8190 ) / 5

Untuk SPL 93 dBA:

Tmax @ 93dBA 

8 2( 9390 ) / 5

Untuk SPL 98 dBA:

8 2( 9690 ) / 5

Tmax @ 98dBA 

Ci C C C  1  2  ....  n Tmax i Tmax1 Tmax 2 Tmax n

D pr int er 

4 .5 2 .1 1. 0 0 .4    27.858 5.278 3.482 2.639

= 0.998 0 998

= 5.278 jam Now, expressing this result as a percentage as required by the problem statement, we have: Dprinter= 99.8%

Untuk SPL 96 dBA:

Tmax @ 96dBA 

n

D

= 3.482 jam

8 = 2.639 jam 2 (9890 ) / 5

The Printing Company that employs these four Printers is not in violation of any established OSHA SPL dosage standards.

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Noise

Noise

Lequivalent = 90 + 16.61 log[D] Lequivalent = 90 + 16.61 log[0.998] g[ ] = 89.987 ~ 90 dBA

4. How much longer is an individual, without hearing protection, permitted to work at a location where the noise level has just been reduced from 104 dBA to 92 dBA?

These Printers experience an equivalent SPL of ~ 90 dBA

To answer this question, we must first determine the OSHA permitted duration, in hours, for each of the two identified noise levels. Tmax = 8 / [2(L-90)/5] For an SPL of 104 dBA: Tmax @ 104 dBA= 8 / [2(104-90)/5] = 1.149 hours For an SPL of 92 dBA: Tmax @ 92 dBA= 8 / [2(92-90)/5] = 6.063 hours The additional time permitted at the lesser noise level of 92 dBA, ΔTmax, is simply the difference between these two OSHA permitted time intervals; thus: ΔTmax=6.063 – 1.149 = 4.914 hours This individual can spend an additional 4.9 hours at a 92 dBA noise level

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