Stres Ergonomik

Stress Ergonomik
Stres Ergonomik
Tekanan Ergonomik Fisik dan Mental
Definisi
= llmu yang mempelajari hubungan manusia dan
lingkungan kerjanya untuk mencapai keseimbangan
dalam efisiensi, kesehatan dan kesejahteraan
= disiplin ilmu yang ditujukan untuk membantu pekerja
bekerja secara produktif, dalam taraf ekonomi yang
dapat diterima oleh pengusaha/pemberi kerja, dan pada
saat yang sama juga memberikan kesejahteraan faali
dan emosional yang tinggi pada pekerja
Disiplin ilmu yang terkait: ilmu rekayasa, fisika, biologi,
sosial dan perilaku
TUJUAN ERGONOMI:
Mencegah tekanan kerja, kelelahan, ketidakpedulian
terhadap kerja, produktivitas rendah, labor turn over rate
yang tinggi
Ilmu--ilmu terkait ergonomik
Ilmu
Engineering sciences: mechanics
Physical sciences: physical energy
stresses
 Biological sciences: anatomy,
anatomy physiology
 biomechanics
 Social and behavioral sciences:
anthropology, (industrial) psychology,
(industrial) sociology  engineering
psychology
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Aplikasi dalam industri
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Orientasi desain dan produksi:
 Human factors in engineering
 Industrial design
 Industrial engineering
g
g
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Orientasi kesehatan/keselamatan:
 Industrial hygiene
 Safety engineering
 Occupational medicine
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Ahli ergonomi harus menguasai:
Ergonomi berhubungan dengan:
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Anatomi, fisiologi memberikan informasi
mengenai struktur dan fungsi tubuh
Anthropometry memberikan informasi
mengenai ukuran tubuh
P ik l i mempelajari
Psikologi,
l j i ffungsii d
darii otak
t kd
dan
sistem syaraf
Higiene industri, mendefiniskan kondisi
pekerjaan yang membuktikan adanya bahaya
terhadap tubuh
Ilmu fisika dan teknik lainnya yang mendukung
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Anatomi--fisiologi tubuh  misal: efisiensi angkat junjung,
Anatomi
telunjuk untuk menunjuk/extension, dari lain untuk operation
System muskulomuskulo-skeletal  keseimbangan beban pada otot
System neuro
neuro--muskuler  kecepatan rekasi/gerak kerja,
kelellahan
System sensorisensori-neural  display, bentuk, diskriminasi
permukaan
k
alat
l t
Pancaindera  display visual, auditory, taktual
System kardiokardio-vaskuler: kelelahan
Biokimia: energi untuk kerja, beban kerja
Gizi, kesehatan: fitness
Dasar desain peralatan industri: handtools, antropometri
Layout ruang kerja
Penempatan peralatan
1
Jenis pekerjaan terbagi:
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KERJA STATIK:
- Sering dilupakan
- ada otot yang lelah
- postur tubuh perlu diperhatikan
- lengkung/bungkuk menyebabkan lelah karena beban
pada satu bagian tubuh, supply oksigen kurang,
buangan
b
terakumulasi,
k
l i otot akan
k llelah
l h
- sebaiknya kerja bergantian statis dan dinamis
KERJA DINAMIK
- Membawa, mengangkat
- perlu diperhatikan sandaran lengan yang empuk
- posisi yang tidak alami perlu dihindari
- karena perbedaan antropometri  alat harus
disesuaikan
Sumber Kelelahan
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Gejala kelelahan
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Perhatian turun
• Kaku dan canggung dalam
Reaksi lamban gerak
Sulit berpikir • Ingin berbaring, susah
berpikir
Kemauan menurun
Lelah bicara
Motivasi kerja• turun
Kurang
g efisien• diMenjadi
kerja
j gugup
Tid k d
dapatt kkonsentrasi
t i
fisik/mental
fisik
/mental • Tidak
• , Sukar
memberi perhatian
Berat di kepala
kepala,
lelah seluruh
• Cenderung lupa
badan
• Kurang percaya diri
Kaki terasa berat
• Cemas
Menguap
• Koordinasi gerak menurun
Pikiran kacau• Kaku di bahu
Mengantuk • Nyeri punggung
Berat mata
Mencegah kelelahan kerja
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Ada perbedaan sistem manusia dan mesin.
Manusia menerima dan memproses informasi kemudian
bertindak
Task stresses, tekanan pada tugas pekerjaan
Yang paling utama adalah fisiologi dan psikologi,
pekerjaan harus sesuai dengan umur, jenis kelamin,
bentuk tubuh pekerja.
Pekerjaan terlalu mudah membosankan, terlalu berat
akan sakit.
Tugas Industrial Hygienist adalah mencari
keseimbangannya.
Aspek postur tubuh: keserasian
tubuh dengan alat kerja, volume
kerja
Aspek rekayasa
Aspek lain: motivasi kerja,
kerja
aturan istirahat, suasana yang
menyenangkan, perbaiki
kesejahteraan termasuk gaji,
gizi.
Kemampuan manusia vs mesin (1)
Hubungan manusia dengan mesin
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Orang yang lelah  mudah mengalami
kecelakaan/cacat dan sakit
Variabel pekerja: usia, jenis kelamin, ukuran
antropometri
Lelah = perasaan yang subyektif
Lelah = penurunan efisiensi kerja fisik dan ketahanan
kerja
S b kkelelahan:
Sumber
l l h
- kelelahan umum
- beban fisik dan mental berat
- kelelahan mental
dan lama
- kelelahan visual
- lingkungan: suhu, bising,
- kelelahan syaraf
iluminasi, cuaca, suasana
- kerja yang monoton
kerja
- sakit badaniah, gizi, kebiasaan makan
- aktor kejiwaan: tanggung jawab, konflik, risau
Manusia unggul dalam
Deteksi rangsang
berenergi rendah
 Melatih pertimbangan
untuk kejadian yang tidak
dapat didefinisikan
 Keuntungan dari
pengalaman dalam
mengambil tindakan
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Mesin unggul dalam
Monitoring
Rutin, berulang
 Deteksi/ambil informasi
dalam waktu singkat
 Operasi dalam lingkungan
berbahaya
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Kemampuan manusia vs mesin (2)
Manusia unggul dalam
Belajar dari pengalaman
dan mengubah jalur
tindakan
 dapat berargumentasi
induktif (dari spesifik ke
general)
 dapat membuat berbagai
solusi alternatif
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Mesin unggul dalam
menghitung hal kompleks
dengan cepat dan akurasi
tinggi
gg
 mengerjakan banyak hal di
waktu yang sama
 respon cepat terhadap
signal control
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Biomekanik
Biomekanika = Mekanika biologi organisme
Biomekanika merupakan alat yang dapat mencegah
beban kerja
Mempelajari fungsi dan struktur bagian tubuh serta
efeknya
y tekanan/beban internal/eksternal terhadapnya.
p y
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Beban berat yang kumulatif dapat menyebabkan
kelainan fisik.
Dirasakan sebagai gejala pertama sakit: sesuatu yang
tidak comfortable
Bila tidak diperhatikan dapat menyebabkan kecelakaan
di kemudian hari
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Contoh Biomekanika
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Tangan dan lengan bawah
kerja tangan dilaksanakan oleh otot yang melekat pada
tulang ulna dan radius  memperhatikan garis fleksi
tangan dan lengan bawah
Contoh: memegang obeng, gegep, dll.
Tungkai bawah
Beberapa titik lemah:
 Daerah belakang lutut
 Bagian bawah dan belakang tungkai atas
 Lengkung bawah kaki
 Jangan menekan bagian ini
Contoh: posisi duduk, bila tidak sesuai akan
menyebabkan kesemutan
Head height
 Allow adequate space for the tallest possible worker.
 Position displays at or below eye level because people naturally look slightly
downward.
Shoulder height
 Control panels should be placed between shoulder and waist height.
 Avoid placing above shoulder height objects or controls that are used often.
Arm reach
 Place items within the shortest arm reach to avoid overover-stretching while reaching up
or outward.
 Position items needed for work so that the tallest worker does not need to bend while
reaching down.
 Keep frequently used materials and tools close to and in front of the body.
Elbow height
 Adjust work surface height so that it is at or below elbow height for most job tasks
tasks.
Hand height
 Make sure that items that have to be lifted are kept between hand and shoulder
height.
Leg length
 Adjust chair height according to leg length and the height of the work surface.
 Allow space so that legs can be outstretched, with enough space for long legs.
 Provide an adjustable footrest so that legs are not dangling and to help the worker
change body position.
Hand size
 Hand grips should fit the hands. Small hand grips are needed for small hands, larger
grips for bigger hands.
 Allow enough work space for the largest hands.
Body size
 Allow enough space at the workstation for the largest worker.
Tungkai bawah
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Kursi terlalu dalam akan
menekan lutut
Kursi terlalu tinggi akan
menekan bagian bawah
belakang tungkai atas
Sandaran kaki,
kaki bila sepatu
empuk, lekuk kaki akan
tertekan
Timbul kesemutan
Pedal kaki yang terlalu
dekat/jauh akan
menyebabkan sudut normal
terlampaui
Mengangkat-junjung
MengangkatMengangkat--junjung benda berat dapat menyebabkan
Mengangkat
terjadinya kecelakaan
Perlu memperhatikan
memperhatikan::
- Variabel kerja
kerja:: lokasi,
lokasi, ukuran obyek
obyek,, ketinggian dari
dan ketempat junjung
junjung,, frekuensi kerja
kerja,, berat obyek
obyek,,
posisi kerja
- Variabel manusia
manusia:: usia
usia,, jenis kelamin
kelamin,, pelatihan
pelatihan,,
fitness, ukuran tubuh
- variabel lingkungan
lingkungan:: temperatur
temperatur,, kelembaban,
kelembaban,
kontaminan di udara
Mengangkat bersama
bersama--sama
Semerata mungkin
mungkin,, jangan terlalu banyak orang
sehingga mengganggu
mengganggu,, sebaiknya sama tinggi,
tinggi, bergerak
bersama--samabersama
sama-komando,
komando, setiap orang pada posisi dan
pegangan yang benar
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Basic ergonomic principles
It is generally most effective to examine work conditions on a case
case--by
by--case basis when
applying ergonomic principles to solve or prevent problems. Sometimes even minor
ergonomic changes in the design of equipment, workstations or job tasks can make
significant improvements in worker comfort, health, safety and productivity.
productivity. The following
are a few examples of ergonomic changes which, if implemented, can result in significant
improvements:
 For assembly jobs, material should be placed in a position such that the worker's
strongest muscles do most of the work.
 For detailed work which involves close inspection of the materials, the workbench
should be lower than for work which is heavy.
 Hand tools that cause discomfort or injury should be modified or replaced. Workers
are often the best source of ideas on ways to improve a tool to make using it more
comfortable. For example, pliers can be either straight or bent, depending on the
need.
 A task should not require workers to stay in awkward positions, such as reaching,
bending, or hunching over for long periods of time.
 Workers need to be trained in proper lifting techniques. A well designed job should
minimize how far and how often workers have to lift.
 Standing work should be minimized, since it is often less tiring to do a job sitting than
standing.
 Job assignments should be rotated to minimize the amount of time a worker spends
doing a highly repetitive task, since repetitive work requires using the same muscles
again and again and is usually very boring.
 Workers and equipment should be positioned so that workers can perform their jobs
with their upper arms at their sides and with their wrists straight.
If the workstation is properly designed, the worker should be able to maintain a
correct and comfortable body posture. This is important because an
uncomfortable work posture can cause a variety of problems, such as:
 back injury;
 development or aggravation of RSIs;
 circulatory problems in the legs.
The main causes of these problems are:
 poorly designed seating;
 standing for long periods;
 reaching too far;
 inadequate
q
lighting
g
g forcing
g the worker to g
get too close to the work.
 The following are some basic ergonomic principles for workstation design. A
general rule of thumb is to consider body size information, such as height,
when choosing and adjusting workstations. Above all, workstations must be
adjusted so that the worker is comfortable.
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5
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v
Interactions between man and such
traditional environmental elements
including all tools and equipment
pertaining to the work place
place.
 The modern concept: man is to be
considered the monitoring link of a manmanmachine environment system.
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Management is interested in the behavior and
physical operating characteristics of man to the
extent that they affect the economic and
productive outputs from such system.
A system is an orderly arrangement of
components which are interrelated and which
act and interact to perform some task or function
in a particular environment.
To achieve maximum efficiency, a manmanmachine system must be designed as a
whole, with man being complementary to
the machine and the machine being
complementary to the abilities of man.
 Consideration should be given to the
general physical and mental demands of
the task, so as not to overload the
operator.
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These ergonomic stresses can impair the health
and efficiency of the worker just as significantly
as the other more common environmental
stresses.
Most men can work for short periods under
overloaded conditions, such as when there are
high production demands; however, when such
an overload reaches some undefinable point,
man may completely breakdown.
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It is essential to recognize that a failure of
malfunction of any component can affect the
other components and thus degrade
performance.
The environment is an important
p
consideration
in a system. Most components (man, tools) in a
system will perform their task properly only
under a given set of conditions.
A component that works well at normal
temperatures may malfunction or fail if placed in
a system near another component that
generates high heat.
Ergonomics includes the physiological and
psychological stresses of the task.
 The task should not require excessive
mental and muscular effort.
effort
 The job should not be so easy that
boredom and inattention lead to
unnecessary errors and accidents.
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The task of the design engineer and safety
professional is to find the happy blend
between “easy” and difficult” jobs.
 With very
y low levels of physiological
p y
g
and
psychological stress, performance is also
low; as stress increases, however,
performance also increases
increases—
—to a point.
 The task is to design jobs that will be
centered around optimum performance.
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Biomechanics—
Biomechanics
—physical demands
Often, the man’s contribution to a system
is to provide a countermeasure in the
event of system malfunction or component
failure.
failure
 To do this he must know that a failure has
occurred and what to do about it.
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Trigger finger (Definition)
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Trigger finger is an inflammation of the
synovial sheath that encloses the flexor
tendons of the thumb and fingers.
Tendons are the cords that connect
bones to muscles in the body. Usually,
tendons slide easily through the sheath
as the finger moves.
In the case of trigger finger, however, the
synovial sheath becomes swollen and the
tendon cannot move easily through small
pulleys in the finger, causing the finger to
remain in a flexed (bent) position. In mild
cases, the finger may be straightened
with a pop, like a trigger being released.
In severe cases, the finger becomes
stuck in the bent position. Usually this
condition can easily be treated; contact
your doctor if you think you may have
trigger finger.
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Symptoms: Symptoms usually begin gradually, and
may consist of burning, tingling, pain, and/or, numbness
in the thumb, index and middle fingers, and in the palm
of the hand. One can usually relate these symptoms to
some activity that is associated with bending the wrists,
such as knitting, typing, or driving. Frequently, these
symptoms will occur during sleep, when many people
sleep with their wrists flexed. As this disease progresses,
one may eventually experience: tingling and numbness
with all finger and hand activities; decreased strength in
g a fist;; and
the hand and thumb;; difficultyy in making
inability to pick up small objects. If the pressure on the
nerve is relieved early enough, the symptoms will usually
be relieved.
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Carpal Tunnel Syndrome is a disease of the wrist and
hand, which is caused by abnormal pressure on the
Median Nerve. As the Median Nerve passes through the
wrist and into the hand, it travels through a tunneltunnel-like
structure called the Carpal Tunnel. This tunnel is located
on the thumb side of the palm of the hand. Within this
tunnel lie tendons, ligaments, blood vessels, and the
Median Nerve, all covered by a nonnon-elastic tissue band
called the Transverse Carpal Ligament. If one or more of
the structures within the Carpal Tunnel become enlarged
or swollen, it exerts pressure on the Median nerve,
causing numbness, tingling, burning, pain, and
weakness in the fingers and hand.
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Causes: There may be a developmental
reason why some people develop this
disease, and others do not. It is felt that
some people are born with a narrower
Carpal Tunnel, and this may predispose
them to Carpal Tunnel Syndrome. With a
narrower Tunnel, it is easier for the Median
Nerve to become compressed. It is felt that
the most common cause of Carpal Tunnel
Syndrome is certain repetitive finger and
thumb motions
motions, when the hand is flexed
either down or up at the wrist. These
motions exert excessive pressure on the
ligaments and tendons that lie within the
Carpal Tunnel. The ligaments and tendons
respond to this excessive pressure by
swelling; and, because the covering of the
Carpal Tunnel is nonnon-elastic (has no "give")
it cannot expand; therefore, the swollen
structures press on the Median Nerve,
causing the above symptoms.
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Those people that are most at risk for experiencing
the symptoms of Carpal Tunnel Syndrome include
those that are engaged in the following activities:
• Computer keyboard typing
• Driving long distances
• Use of tools that produce vibrations in the hand,
such as: hammers, saws, drills, and jackjack-hammers
• Repetitive assembly line work
• Folding
g materials such as laundry
y and p
paper
p
products
• Knitting and sewing
Other, less common causes of Carpal Tunnel
swelling may include cysts, tumors, fluid retention
during pregnancy, arthritis, and wrist fractures.
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Other treatment tips, which should be used
in conjunction with the above products
include:
• Applying ice to the palm and wrist, may
help to reduce swelling and pain. Always
apply the ice so that it is soothing, and not
uncomfortably cold.
• Try to prevent your wrist from flexing and
extending when doing chores. The Carpal
Lock will do this for you.
• When using tools, make sure the handle
fits your hand, and you can grasp the tool
with your whole hand, rather than grasping
with the tips of your fingers or thumbs.
• Reduce the speed your wrist and hands
work at.
• Exercise your wrists and hands regularly
at work. Take a one minute break every 30
minutes to perform some of the exercises
shown below.
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Relief for Carpal Tunnel
Syndrome: The most effective
treatment that is recommended
by physicians and therapists is
immobilizing the wrist in a
splint, to minimize and prevent
those wrist motions which
cause swelling in the Carpal
Tunnel. This will reduce the
pressure on the Median Nerve,
and help to alleviate the
symptoms of Carpal Tunnel
Syndrome.
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1. RangeRange-ofof-motion exercises
exercises:: Clench fist tightly
for 5 seconds, then release, straightening your
fingers all the way and keep them straight for 5
seconds. Repeat 5 times for each hand.
2.
2 Stretching exercises:
exercises: Using one hand
hand, bend
the fingers of the other hand gently as far as you
can, stretching the fingers and wrist. Hold for 5
seconds. Repeat 5 times for each hand.
3. Isometric exercises:
exercises: Clench fist with palm
facing up. Use other hand to push down on fist,
while providing resistance with the fist. Hold for 5
seconds. Repeat with palm of clenched fist facing
down. Repeat 5 times for each hand.
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Bunch up
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Display
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Display atau control untuk kepentingan
keamanan kerja
Display merupakan input bagi pekerja
Dapat berupa display visual, auditori ataupun
t kt l
taktual
Display untuk mengecek, kuantitatif dan kualitatif
 menunjukkan bagaimana mesin berfungsi
Kesalahan mengartikan informasi dan tidak
jelasnya display pada peralatan  kesalahan
operasi, kecelakaan
User friendly?
The result is….
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Ergonomics
Vs
?
Adjust in height by simply lifting up on the platform!
This unique design allows the CPU
to extend past the worksurface
and swivel 360°.
The Sit or Stand Table provides superior workstation
efficiency and comfort. With a touch of a button, the
table can be raised or lowered to the desired height.
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