pak pertemuan 1 nihl

Noise Induced Hearing Loss

KEBISINGAN (NOISE)

•

_{UNWANTED/UNDESIRED SOUND}

•

_{HIGH INTENSITY AND OR FREQUENCY}

Pendahuluan

• _{Pendengaran indra penting untuk komunikasi} penurunan pendengaran / ketulian  dampak psikologis & sosial

• _{Occupational Hearing Loss : NIHL, Trauma akustik}

• _{NIHL berhubungan dengan paparan kebisingan}

jangka lama. Kerusakan terjadi pelan dan baru disadari setelah beberapa tahun kemudian. Irreversible HL  Tindakan preventif penting

• _{Trauma akustik akibat paparan tunggal dengan}

WHY IS THERE SO MUCH NOISE?

•

_{INDUSTRIALISASI}

_MEKANISASI

•

_{PENGGUNAAN POWER DI INDUSTRI}

MENINGKAT

•

_{PENGEMBANGAN MESIN-MESIN BARU}

LEBIH CEPAT DARI PADA PENGEMBANGAN

METODE UNTUK REDUKSI KEBISINGAN

Noise Induced Hearing Loss

- Levels of Environmental Sounds

Source—Safe Levels dBA SPL

Heavy Traffic 80

Automobile (at 20 meters) 70

Vacuum Cleaner 65

Conversational Speech (at 1 meter) 60 Quiet Business Office 50

Residential Area at Night 40 Whisper, Rustle of Leaves 20

Rustle of Leaves 10

KEBISINGAN DIANGGAP MEMBAHAYAKAN

JIKA

• _{DI TEMPAT KERJA KITA HARUS BERTERIAK AGAR} SUARA DAPAT DIDENGAR

• _{KURANG DAPAT MENDENGAR / TELINGA} BERDENGING SEHABIS BEKERJA

• _{ORANG LAIN/ KELUARGA YG MENGENALI} • _{COCKTAIL PARTY DEAFNESS}

• _{NAKER BANYAK YANG TULI}

PENGARUH BISING PADA PEKERJA

• _{Masalah Pendengaran} • _{Masalah lain:}

a. Gangguan fisiologi : meningkatnya Tekanan Darah, Denyut Nadi, Metabolisme Basal, Vasokonstriksi

Pembuluh Darah, ischemic heart disease, ketegangan otot (rangsangan sistem syaraf otonom)

EFEK KEBISINGAN TERHADAP PENDENGARAN

1. TRAUMA AKUSTIK

• _{AKIBAT PAJANAN TUNGGAL (SINGGLE EXPOSURE) DG} INTENSITAS SANGAT TINGGI & TIBA-2 (EX: LEDAKAN BOM)

• _{EFEK :}

• _{MT ROBEK}

• _{DISLOKASI ATAU KERUSAKAN TL PENDENGARAN &} SEL SENSORIS ORGANON CORTI

Masalah Pendengaran

•

_{2 KATEGORI KETULIAN}

– _{TULI KONDUKSI}

TUL KONDUKTIF

• _{GANGGUAN PADA TELINGA BAGIAN LUAR DAN} TENGAH

• _{SERUMEN OBSTRUKTIF}

• _{RUPTURA MEMBRANA TYMPANI (EXPLOSION,}

MEASLES) ROBEK 1/3 BAGIAN PULIH DLM 9 BLN • _{TERSUMBATNYA TUBA EUSTACHI (KOTORAN,}

BENGKAK)

TULI PERSEPTIF

•

_{GANGGUAN PADA TELINGA BAGIAN DALAM}

•

_{KERUSAKAN TELINGA BAGIAN DALAM :}

PRESBYACUSIS

•

_{BEGIN AT A EARLY AGE (EARLY TEENS)}

•

_{THE HAIR CELLS AT THE BASE OF THE COCHLEA}

WHICH RESPOND TO THE HIGHER FREQUENCY

ARE AFFECTED FIRST

BERBAGAI PENYEBAB TULI PERSEPTIF

• _{KONGENITAL (RUBELLA, INFLUENSA PADA IBU PD} TRIMESTER I KEHAMILAN, OBAT-OBATAN)

• _{ACCIDENTS AT BIRTH (MEASLES---BILATERAL, MUMPS} ----UNILATERAL)

• _OTOTOXICITY

• _{FRACTUR BASIS CRANII}

• _{NERVE DEAFNESS (COMPLETE LOSS OF HEARING)} • _PRESBYACUSIS

PRESBYACUSIS DAN NIHL

•

_{MERUPAKAN PENYEBAB TULI PERSEPTIF YANG}

Presbyacusis

• _{Accounting for presbycusis is not mandatory but it is} often done in the legal setting. What is actually

sought is to account for non-occupational hearing loss. Seven states allow deductions for presbycusis. • _{Or to answer the question: Is the progression of}

Presbyacusis

• _{NIOSH does NOT recommend accounting for}

presbycusis when looking for Medical Causation of a progressive hearing loss. If a worker has a

progressive hearing loss it is assumed to be due to noise trauma and corrective measures should be taken.

• _{However, estimation of presbycusis is used for}

Presbycusis

--Sex Difference

• _{Several researchers have studied primitive cultures to}

determine the influence of aging on hearing acuity in the absence of occupational noise. These studies found aging effects on hearing, but observed no sex difference in the hearing loss. Goycoolea MV, 1986; Rosen S, 1962

• _{Animal studies have also found no sex difference.}

Hunter KP, 1987

• _{It has been proposed that the difference between male and}

female thresholds as a function of age, is due to

Handicap Equations

Presbycusis used to Project Hearing Loss

•

_{It is assumed with all of the calculators that}

hearing loss due to noise and presbycusis are

additive.

•

_{ISO 1999 compression factor is applied when}

projecting audiometric data.

Hearing Loss = ARL + NIL - (ARL * NIL)/120

NIHL

• _{NIHL mengenai kedua telinga}

• _{Tahap awal hanya dapat diketahui dengan tes} pendengaran. Pekerja yang terkena bisa tidak menyadarinya ( walaupun audiogram ada dip di 4000Hz)

• _{Keluhan lain bisa menyertai yaitu mendenging} (Tinnitus), recruitment, vertigo

• _{Tahap berat timbul kesulitan menangkap}

pembicaraan dan terganggu komunikasinya 

Pekerja beresiko

:

Intensitas kebisingan tinggi dengan akitivitas menggunakan peralatan kecepatan tinggi : • _Grinding

• _Sawing • _Drilling

Biasanya pada tempat produksi : • _Metal

Patogenesis NIHL

• _{Adaptasi : fisiologis, sebagai pertahanan tubuh, reversibel  kembali}

cepat

Fenomena Fisiologis

Terjadi bila terpajan bising 70 db

Nama lain : per-Stimulatory Fatigue, pemulihan biasanya terjadi dalam setengah detik

• _{Ambang Pendengaran berkurang sementara}

TTS : patologis, terjadi perubahan metabolik

reversibel  kembali lambat (bbrp menit—jam) TERJADI PADA PAJANAN > 85 dBA

• _{Berkurang secara menetap}

2. TEMPORARY THRESHOLD SHIFT (TTS)

•

_{GANGGUAN BERSIFAT SEMENTARA}

•

_{TIMBUL KARENA KELELAHAN SYARAF}

•

_{WAKTU PULIH BEBERAPA MENIT SAMPAI}

BEBERAPA JAM (MAKSIMUM 10 JAM

•

_{JIKA DALAM 10-14 JAM BELUM PULIH}

----PERSISTEN THRESHOLD SHIFT

•

_{JIKA DALAM 40 JAM BELUM PULIH}

3.PERMANEN THRESHOLD SHIFT

•

_{= NIHL (NOISE INDUCED HEARING LOSS)}

•

_{AKIBAT PAPARAN BISING BERULANG ,}

SEBELUM PEMULIHAN SECARA

LENGKAP---AKUMULASI SISA TTS

•

_{SETELAH ≥10 TAHUN}

•

_{TERJADI PERLAHAN-LAHAN –NAKER TAK}

Histopatologi

• _{Degenerasi sel rambut (luar) organ corti} • _{Fase awal : 3  6 kHz (terutama 4 kHz )}

• _{Fase lanjut mengenai frekwensi yang lebih} luas

• _{Kebisingan intensitas sedang menyebabkan} gangguan metabolisme  degenerasi

Kerusakan organ :

Organ Corti ,

membrane, stereocilia, haircell,

Source –dangerous level dBA SPL

Produces pain 140 – 150

Jet aircraft during takeoff (20

meters) ₁₃₀

Discomfort level, tractor without

cab ₁₂₀

Rock concert

110

Hammer,chain saw, pneumatic

drill _{100 – 105}

Semi-trailers (20 meters)

Source dBA SPL

Heavy traffic 80

Automobile (20 meters) 70

Vacuum cleaner 65

Conversational speech (1 meter) 60

Quiet business office 50

Residential area at night 40

Whisper, 20

CIRI KHAS NIHL

• _TINNITUS

• _{SULIT MENDENGAR DERING TELEPHONE}

• _{SULIT MENDENGAR PERCAKAPAN ORANG LAIN}

DENGAN JELAS TERUTAMA DI TEMPAT YANG RAMAI DAN BISING

• _{TANPA RASA NYERI (TIDAK DISADARI)}

• _{After 10 years of exposure, the damage caused by} noise remains constant, but presbycusis progresses as predicted.

Noise Induced Hearing Loss

- Characteristics

•

_{Sensory hearing loss with loss of}

discrimination commensurate with the loss in

hearing.

•

_{Maximum in the high frequencies sometimes}

with a 4000 Hz Notch.

NIHL

• _{ORANG B ARU SADAR AKAN ADANYA NIHL JIKA :}

– _{KEHILANGAN PENDENGARAN MENCAPAI FREK}

PEMBICARAAN (500-1000-2000 Hz)

– _{GEJALA AWAL :TINNITUS , TELINGA TERASA TERSUMBAT} – _{KURANG DENGAR FREKUENSI TINGGI (“T” , “D” PADA}

AHIR KATA), SUARA ANAK-ANAK PADA JARAK JAUH , PEMBICARAAN PADA TEMPAT RAMAI, WALAU JARAK LAWAN BICARA DEKAT)

Diagnosa NIHL

• _{Anamnesis :}

- Usia- atherosclerosis; hipertensi;proses penuaan

- Lama bekerja

- Riwayat penyakit (peny.telinga sebelumnya) - Riwayat trauma

- Onset Penurunan pendengaran

 mendadak, berangsur-angsur

- Riwayat Pekerjaan :Bising di tempat kerja > 85 dBA, lama pajanan per hari, penggunaan APT

FAKTOR YANG BERPENGARUH

Riwayat penyakit

•

_{Masalah telinga dan gejalanya}

•

_{Riwayat trauma kepala atau telinga}

•

_{Pemakaian obat-obatan}

•

_{Pekerjaan sebelumnya, militer}

•

_{Paparan bahan beracun /}

toxic(CO,CS2,Trichlorethylene)

•

_{Aktivitas diluar pekerjaan}

FAKTOR YANG BERPENGARUH

Riwayat paparan kebisingan

•

_{Intensitas bising}

•

_{Tipe bising ( spektrum frekwensi )}

•

_{Sifat bising}

•

_{Jarak dengan sumber bunyi}

•

_{Posisi telinga}

Pemeriksaan Fisik

:

a. Keadaan Umum.

b. Pemeriksaan

telinga.

c. Otoskopi.

TES AUDIOMETRI

• _{NADA MURNI}

• _{AIR CONDUCTION}

• _{PEMERIKSAAN AMBANG PENDENGARAN MINIMAL} PADA FREKUENSI 500,1000,2000,30000,4000 DAN 6000 HZ

• _{JIKA DITEMUKAN PERGESERAN NAD YG BERMAKNA} (>10dB) PADA 2000,3000,4000 HZ DIBANDING

PERSYARATAN UNTUK TES AUDIOMETRI

•

_{TEMPAT PEMERIKSAAN HARUS SUNYI (MAKS.}

40 dB)

•

_KALIBRASI

•

_{CERTIFIED OPERATOR/ YANG TELAH}

Indikasi NIHL-audiogram

1.KETULIAN PADA FREK 3000-6000 Hz

2. ACCOUSTICAL DIP PADA4000 Hz

3. PADA TRAUMA AKUSTIK , KETULIAN

BIASANYA BILATERAL

4. JIKA UNILATERAL SERING KARENA OMP

5. NIHL JUGA SERING UNILATERAL PADA

AUDIOMETRI

BANDINGKAN HASIL AUDIOGRAM DENGAN

PEMERIKSAAN SEBELUMNYA

JIKA ADA PENINGKATAN YANG SIGNIFIKAN ,

ULANG 1 BULAN KEMUDIAN

JIKA PERSISTEN: PINDAHKAN KE TEMPAT YANG

TIDAK BISING; UKUR KEBISINGAN,

AUDIOMETRI

• _{PALING SEDIKIT DILAKUKAN 14 JAM (TANPA}

PAJANAN) , PERLU DIGUNAKAN ALAT PELINDUNG TELINGA

• _{FREKUENSI 250-8000 HZ} • _{RUANGAN SUNYI}

• _{NADA MURNI}

• _{NAIKKAN INTENSITAS tiap 10 dB}

• _{SETELAH PASIEN MERESPON, TURUNKAN 5 dB-5 dB} dst, sampai tak dapat didengar

Penanganan NIHL

• _{Fase akut dengan terapi vasodilatator} • _{Ketulian berakibat gangguan komunikasi}

- diperlukan konseling

- rehabilitatif :  latihan mendengar

 latihan membaca gerak bibir  Alat Bantu Dengar

Noise Induced Hearing Loss

- Noise Levels

•

_{Individuals have different susceptibilities to}

noise.

(Kyong-Myong Chon, 1996)

•

_{Noise levels are measured in dB SPL on the A}

Scale.

•

_{Impulse Noise is more damaging than a}

Plaintiff Evaluation

-History is very important

• _{Other ear diseases can cause a hearing loss.}

• _{Other associated systemic diseases which can cause a} hearing loss.

• _{Other exposure to noise trauma. This is very}

important because noise exposure’s effects on the inner ear are finite and will cause no further damage after approximately 10 years. Thus, it could be

argued that the plaintiff's occupational exposure to noise caused no harm because of his

Plaintiff Evaluation

- Other ear diseases can cause a hearing loss

•

_Vertigo

- Endolymphatic Hydrops - Perilymph Fistula

•

_Dizziness

•

_{Eustachian Tube Dysfunction}

Plaintiff Evaluation

- Other systemic diseases which are associated with hearing loss (nosocusis)

Vascular Disease

• _Diabetes

• _{Heart Disease} • _Smoking

• _{Hyperlipidemia}

Rosenhall U, Penderson KE Presbycusis and Occupational Hearing Loss

Occup Med 10(3):593-607,1995

• _{Ototoxic Drug Use}

• _{Otologic Ear Infections} • _Meningitis

Plaintiff Evaluation

- Other exposure to noise trauma (Sociocusis)

•

_Hunting.

_{Kryter KD, 1991 found that 69% of}

9800 railroad workers used guns.

Most have an asymmetrical hearing loss.

(Job A, Grateau P, Picard J, 1998)

•

_{Home machinery – Lawn mowers, weed}

trimmers, etc.

•

_{Chain saws}

•

_{Loud Music, Rock Concerts}

FAKTOR YANG BERINTERAKSI DENGAN BISING

•

_{USIA : ATHEROSCLEROSIS; HIPERTENSI;PROSES}

PENUAAN

•

_GETARAN

•

_{PENGGUNAAN ZAT OTOTOXIC}

Ototoxins

•_{Organic solvents}

–_{** Toluene (printing)} –_{** Xylenes (plastics)} –_{** Styrenes (plastics)}

–_{** Trichloroethylene (degrease)} –_{* Carbon Disulfide (textile)}

–_{* Stoddard/white spirits} –_{* N-hexane}

– _{Fuels (JP-8 fuel)} – _{Ethyl benzene}

– _{Perchloroethylene} – _{Butyl Nitrite}

– _{Methylene chloride}

Metals

* Mercury and derivatives * Lead and derivatives * Arsenic (atoxyl)

* Manganese

 Trimethyltin (organic

tin)

 Cobalt

Asphyxiants

** Carbon Monoxide * Cyanide

Army ID: * potential ** high-priority

Drugs

 Aminoglycosides  Loop diuretics

 Anti-neoplastic agents  ASA (acetyl salyilic acid)  Quinine compounds

Others

 Chem. warfare nerve

agents (ex: sarin)

 Organophosphate

(pesticide)

Morata,TC., Dunn,DE., Kretschmer, LW., Lemasters, GK., Keith, RW., Scandinavian Journal of Work, Environment & Health, 19(4):

245-54, 1993 Aug.

• _{Paint and print industries - risk of hearing loss}

– _{Unexposed (no noise or solvent)}

– _{Noise exposed only – hearing loss risk 4x} – _{Toluene solvent only – hearing loss risk 5x}

– _{Toluene solvents and noise –hearing loss risk 11x}

Controls: previous exposure to noise and/or chemicals, medical and audiological history, age, length of

employment, recreational exposure, and military service Tests: puretones, immittance (tympanograms, reflexes,

Problems caused by solvents

• _{Hearing Loss}

– _{Sensorineural Hearing Loss - Inner Ear}

• _{Tuning (clarity and loudness)}

• _{Testing: common audiometric procedures (Puretones, Speech, Other)}

– _{Central/Retrocochlear Hearing Loss - Brainstem and Cortex}

• _{Processing (transmission, cognition, varying degrees of tuning and loudness)} • _Testing:

– Speech Processing (interrupted speech, speech in noise, temporal integration)

– Evoked Potentials (brainstem or cortical potentials),

– DPOAE: Contra-lateral suppression (efferent testing)

– _{Reflex and Reflex Decay}

– Modified Puretone: masking level difference, gap detection, duration pattern, pitch pattern, temporal integration, high frequency audiometry, step size less 5dB

– _{Questionnaire on speech discrimination difficulties or other auditory problems that}

are inconsistent with thresholds

Lead (pb)

•

_{Example Audiogram taken from literature.}

.5K 1K 2K 3K 4K 6K 8K

30 35 40 45 40

60 70

Arsenic (As)

•

_{Example Audiogram taken from literature.}

.5K 1K 2K 3K 4K 6K 8K

45

30 10 05 10 15 15

•

_{Hearing losses are greater in the lower}

frequencies at 125, 250, and 500 Hz.

Mercury (Hg)

Example Audiogram taken from literature. .5K 1K 2K 3K 4K 6K 8K

25 30 35 40 45 50 55

• _{Hearing loss is in the entire range with greater}

losses in the high frequencies.

• _{However, loss does not always occur even with} severe neurological symptoms.

Organic Solvents

•

_{In the}

_{early stages}

_{oto-neurologic}

disturbances may include

vertigo

and

nausea.

•

_{Histopathologic studies have shown}

_{damage in}

Organic Solvent- CS2

•

_{Used in}

_{solvents and insecticide}

•

_Noise

_{86-89 dBA + CS2}

_

_{hearing loss within}

₂

years

of exposure :

47%

•

_Within

_{3 years}

_

_incidence

_71%

•

_Audiometric

_

_{losses in high freq}

•

_{Example Audiogram taken from literature.}

Organic Solvents-Tri Chlor Ethylene

•

_{This solvent is used as a}

_{degreaser, dry}

cleaning agent, spot remover and rug cleaner.

•

_{It is used in the production of paints, waxes,}

pesticides, adhesives and lubricants.

•

_{Destruction of sensory cells of the inner ear}

_is

Organic Solvents-Tri Chlor Ethylene

•

_{It results in a}

_{bilateral symmetrical high}

frequency dip beginning at 2K or 3K Hz and is

associated with balance problems

Example Audiogram taken from literature.

.5K 1K 2K 3K 4K 6K 8K

Styrene

• _{Styrene is used in the production of plastics,}

synthetic rubber, resins and insulating materials

• _{Lower concentrations of styrene show losses above}

8 KHz and do not indicate loss other than noise (gambaran mirip dengan NIHL)

Example Audiogram taken from literature. .5K 1K 2K 3K 4K 6K 8K

Styrene

•

_{Higher concentrations (}

_{1200 ppm}

_{) have losses}

at

all frequencies.

Example Audiogram taken from literature.

.5K 1K 2K 3K 4K 6K 8K

Xylene

•

_the

_{most prevalent}

_{, exposing more people}

•

_the

_{most toxic}

_{of all the organic solvents}

•

_{found in}

_{paints, varnishes, and thinners.}

•

_{It produces}

_{damage in the sensory cells}

_{of the}

inner ear.

•

_{No configurations were found discussed in}

Toluene

•

_{the most studied organic solvent}

_.

•

_{Uses: manufacturing of chemicals, paints,}

lacquers (pernis), adhesives, rubber, printing,

leather tanning, spray painting, glue, etc.

Toluene

•

_{Noise + toluene}

_

_increased

_{risk 27.5 times.}

•

_{Balance problems and abnormal acoustic}

reflexes are significant symptoms.

•

_{The audiogram configuration can be}

_flat,

bilateral or unilateral;

•

_however

_{the most common configuration is a}

Toluene

•

_{Example Audiogram taken from literature.}

PENATALAKSANAAN

•

_{GUNAKAN APT}

•

_{PEMERIKSAAN PENDENGARAN : AUDIOMETRI}

NADA MURNI : 16-36 JAM BEBAS PAJANAN

BISING, LAKUKAN SECARA BERKALA

•

_{SESUAI DENGAN PENYEBAB}

KETULIAN---PINDAH TEMPAT KERJA (KE TEMPAT YG TDK

BISING)

Macam Alat Bantu Dengar

Behind The ear In the Ear

Penanganan NIHL

• _{Fase akut dengan terapi vasodilatator} • _{Ketulian berakibat gangguan komunikasi}

- diperlukan konseling

- rehabilitatif :  latihan mendengar

 latihan membaca gerak bibir  Alat Bantu Dengar

PROGNOSIS

•

_IRREVERSIBLE

•

_{PENCEGAHAN MERUPAKAN HAL YANG}

PROGRAM PEMELIHARAAN

PENDENGARAN

•

_{PERLU KERJA SAMA ANTARA:}

LABOR

MANAGE MENT

OBJECTIVES OF HCP

• EDUCATES EMPLOYERS AND EMPLOYEES

ABOUT THE NATURE OF HEARING LOSS (IRREVERSIBLE, SUBTLE IN ONSET,

PSYCHOLOGICALLY DISTRESSING IF SEVERE)

• DIAGNOSIS HEARING LOSS AT EARLY STAGES

• PROVIDES AND DEMONSTRATES THE PROPER

WHAT IS THE MINIMUM OF HCP?

•

_{A BASELINE AUDIOGRAMS FOR ALL}

EMPLOYEES (AT RISK)

•

_{ANNUAL AUDOGRAM FOR EACH EMPLOYEE}

EXPOSED TO 85 dB/greater

SUCH SERIAL AUDIOGRAMS CAN DETECT NIHL

EARLY AND PREVENT FURTHER PROGRESSION

OF IT BEFORE THE NOTCH WIDENS TO IMPAIR

THE SPEACH FREQUENCIES (500-1000-2000

Pengendalian secara teknis

•

_{Substitusi, eliminasi, upgrade : penggantian}

alat dgn kebisingan tinggi

•

_{Isolasi : sound box, sound enclosure}

•

_{Sound Barrier : sound proof materials to}

block the transmission

of noise

•

_{Acoustic Design : sound absorbent}

Kontrol Administratif

•

_Rotasi

•

_{Jadwal produksi}

_

_{mengurangi kontinuitas}

kebisingan

•

_{Menggunakan kontrol dan monitoring}

kebisingan

•

_{Edukasi dan training tentang :}

Kesehatan telinga, bagaimana menggunakan

alat pelindung / proteksi

Personal Protective Equipment

Macam Ear plugs :

- Ear plug Bilsom 556 (ANSI S3.19- 1974) NRR : 27 dB - Ear plug 3M 1270 (C.A. 9584) NRR : 25 dB

Keberhasilan HLPP

•

_{Parameter :}

–

_{Menerapkan secara benar program}

prevensi ( HLPP )

–

_{Mengendalikan intensitas kebisingan di}

tempat kerja

–

_{Penemuan kasus, insiden and prevalensi}

Hambatan HLPP

•

_{Kesulitan diagnosis NIHL sebagai penyakit}

akibat kerja :

–

_{Paparan kebisingan diluar pekerjaan}

–

_{Penyakit lain yang berpengaruh terhadap}

pendengaran

–

_{Tidak adanya data dasar audiogram}

•

_{Kurang disiplin memakai Alat proteksi}

•

_{Mesin dan peralatan yang digunakan sudah}

Penelitian di Surabaya

Pengaruh kebisingan terhadap pendengaran

Rus Suheryanto ( 1993)

•

_{64 Karyawan pabrik textil}

•

_{Kebisingan 95-99 dBA}

•

_{30 orang NIHL}

Penelitian di Surabaya

NOISE INDUCED HEARING LOOS IN STEEL FACTORY WORKERS

Heri Kabullah, Sri Harmadji ( 2004)

Penelitian lain

• _{Hendarmin 1971 : NIHL pada 50% karyawan}

Manufactur Plant Pertamina

• _{Hendarmin,Hadjar : kebisingan jalan 95 dbA} • _{Sundari 1994 : NIHL 31,55% pada karyawan}

Industri besi di Jakarta , noise intensity : 85-105 db

• _{Lusianawaty 1998 : NIHL 31,8% pada pekerja}

industri kayu di Jawa Barat , noise intensity : 84,9-108,2 db

• _{Bashiruddin 2002 NIHL 44,5% pada sopir bajaj,}