Stress Ergonomik
Stres Ergonomik Tekanan Ergonomik Fisik dan Mental
Definisi = llmu yang mempelajari hubungan manusia dan lingkungan kerjanya untuk mencapai keseimbangan dalam efisiensi, efisiensi, kesehatan dan kesejahteraan = disiplin ilmu yang ditujukan untuk membantu pekerja bekerja secara produktif, produktif, dalam taraf ekonomi yang dapat diterima oleh pengusaha/pemberi kerja, kerja, dan pada saat yang sama juga memberikan kesejahteraan faali dan emosional yang tinggi pada pekerja Disiplin ilmu yang terkait: terkait: ilmu rekayasa, rekayasa, fisika, fisika, biologi, biologi, sosial dan perilaku TUJUAN ERGONOMI: Mencegah tekanan kerja, kerja, kelelahan, kelelahan, ketidakpedulian terhadap kerja, kerja, produktivitas rendah, rendah, labor turn over rate yang tinggi
Ilmu-ilmu terkait ergonomik Engineering sciences: mechanics Physical sciences: physical energy stresses z Biological sciences: anatomy, physiology Æ biomechanics z Social and behavioral sciences: anthropology, (industrial) psychology, (industrial) sociology Æ engineering psychology z
Aplikasi dalam industri z
Orientasi desain dan produksi: produksi: z Human factors in engineering z Industrial design z Industrial engineering
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Orientasi kesehatan/keselamatan: kesehatan/keselamatan: z Industrial hygiene z Safety engineering z Occupational medicine
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Ergonomi berhubungan dengan: z z z z
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Anatomi, Anatomi, fisiologi memberikan informasi mengenai struktur dan fungsi tubuh Anthropometry memberikan informasi mengenai ukuran tubuh Psikologi, Psikologi, mempelajari fungsi dari otak dan sistem syaraf Higiene industri, industri, mendefiniskan kondisi pekerjaan yang membuktikan adanya bahaya terhadap tubuh Ilmu fisika dan teknik lainnya yang mendukung
Ahli ergonomi harus menguasai: menguasai: z z z z z z z z z z z
AnatomiAnatomi-fisiologi tubuh Æ misal: misal: efisiensi angkat junjung, junjung, telunjuk untuk menunjuk/extension, menunjuk/extension, dari lain untuk operation System muskulomuskulo-skeletal Æ keseimbangan beban pada otot System neuroneuro-muskuler Æ kecepatan rekasi/gerak kerja, kerja, kelellahan System sensorisensori-neural Æ display, bentuk, bentuk, diskriminasi permukaan alat Pancaindera Æ display visual, auditory, taktual System kardiokardio-vaskuler: vaskuler: kelelahan Biokimia: Biokimia: energi untuk kerja, kerja, beban kerja Gizi, Gizi, kesehatan: kesehatan: fitness Dasar desain peralatan industri: industri: handtools, handtools, antropometri Layout ruang kerja Penempatan peralatan
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Jenis pekerjaan terbagi: z
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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, tubuh, supply oksigen kurang, kurang, buangan terakumulasi, terakumulasi, otot akan lelah - sebaiknya kerja bergantian statis dan dinamis KERJA DINAMIK - Membawa, Membawa, mengangkat - perlu diperhatikan sandaran lengan yang empuk - posisi yang tidak alami perlu dihindari - karena perbedaan antropometri Æ alat harus disesuaikan
Sumber Kelelahan z z z
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Gejala kelelahan z z z z z z z z z z z z
Perhatian turun Reaksi lamban Sulit berpikir Kemauan menurun Motivasi kerja turun Kurang efisien di kerja fisik/mental fisik/mental Berat di kepala, kepala, lelah seluruh badan Kaki terasa berat Menguap Pikiran kacau Mengantuk Berat mata
• Kaku dan canggung dalam gerak • Ingin berbaring, susah berpikir • Lelah bicara • Menjadi gugup • Tidak dapat konsentrasi • Sukar memberi perhatian • Cenderung lupa • Kurang percaya diri • Cemas • Koordinasi gerak menurun • Kaku di bahu • Nyeri punggung
Mencegah kelelahan kerja z
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Ada perbedaan sistem manusia dan mesin. mesin. Manusia menerima dan memproses informasi kemudian bertindak Task stresses, tekanan pada tugas pekerjaan Yang paling utama adalah fisiologi dan psikologi, psikologi, pekerjaan harus sesuai dengan umur, umur, jenis kelamin, kelamin, bentuk tubuh pekerja. pekerja. Pekerjaan terlalu mudah membosankan, membosankan, terlalu berat akan sakit. sakit. Tugas Industrial Hygienist adalah mencari keseimbangannya. keseimbangannya.
Aspek postur tubuh: tubuh: keserasian tubuh dengan alat kerja, kerja, volume kerja Aspek rekayasa Aspek lain: motivasi kerja, kerja, aturan istirahat, istirahat, suasana yang menyenangkan, menyenangkan, perbaiki kesejahteraan termasuk gaji, gaji, gizi. gizi.
Kemampuan manusia vs mesin (1)
Hubungan manusia dengan mesin z
Orang yang lelah Æ mudah mengalami kecelakaan/cacat dan sakit Variabel pekerja: pekerja: usia, usia, jenis kelamin, kelamin, ukuran antropometri Lelah = perasaan yang subyektif Lelah = penurunan efisiensi kerja fisik dan ketahanan kerja Sumber kelelahan: kelelahan: - kelelahan umum - beban fisik dan mental berat - kelelahan mental dan lama - kelelahan visual - lingkungan: lingkungan: suhu, suhu, bising, bising, - kelelahan syaraf iluminasi, iluminasi, cuaca, cuaca, suasana - kerja yang monoton kerja - sakit badaniah, badaniah, gizi, gizi, kebiasaan makan - aktor kejiwaan: jawab, konflik, konflik, risau kejiwaan: tanggung jawab,
Manusia unggul dalam Deteksi rangsang berenergi rendah z Melatih pertimbangan untuk kejadian yang tidak dapat didefinisikan z Keuntungan dari pengalaman dalam mengambil tindakan z
Mesin unggul dalam Monitoring Rutin, Rutin, berulang z Deteksi/ambil informasi dalam waktu singkat z Operasi dalam lingkungan berbahaya z z
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Kemampuan manusia vs mesin (2) Manusia unggul dalam Belajar dari pengalaman dan mengubah jalur tindakan z dapat berargumentasi induktif (dari spesifik ke general) z dapat membuat berbagai solusi alternatif z
Mesin unggul dalam menghitung hal kompleks dengan cepat dan akurasi tinggi z mengerjakan banyak hal di waktu yang sama z respon cepat terhadap signal control z
Biomekanik Biomekanika = Mekanika biologi organisme Biomekanika merupakan alat yang dapat mencegah beban kerja Mempelajari fungsi dan struktur bagian tubuh serta efeknya tekanan/beban internal/eksternal internal/eksternal terhadapnya. terhadapnya.
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Beban berat yang kumulatif dapat menyebabkan kelainan fisik. fisik. Dirasakan sebagai gejala pertama sakit: sakit: sesuatu yang tidak comfortable Bila tidak diperhatikan dapat menyebabkan kecelakaan di kemudian hari
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Contoh Biomekanika z
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Tangan dan lengan bawah kerja tangan dilaksanakan oleh otot yang melekat pada tulang ulna dan radius Æ memperhatikan garis fleksi tangan dan lengan bawah Contoh: Contoh: memegang obeng, obeng, gegep, gegep, dll. dll. Tungkai bawah Beberapa titik lemah: lemah: z Daerah belakang lutut z Bagian bawah dan belakang tungkai atas z Lengkung bawah kaki Æ Jangan menekan bagian ini Contoh: Contoh: posisi duduk, 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 z Control panels should be placed between shoulder and waist height. height. z Avoid placing above shoulder height objects or controls that are used often. Arm reach z Place items within the shortest arm reach to avoid overover-stretching while reaching up or outward. z Position items needed for work so that the tallest worker does not not need to bend while reaching down. z Keep frequently used materials and tools close to and in front of of the body. Elbow height z Adjust work surface height so that it is at or below elbow height height for most job tasks. Hand height z Make sure that items that have to be lifted are kept between hand hand and shoulder height. Leg length z Adjust chair height according to leg length and the height of the the work surface. z Allow space so that legs can be outstretched, with enough space for long legs. z Provide an adjustable footrest so that legs are not dangling and to help the worker change body position. Hand size z Hand grips should fit the hands. Small hand grips are needed for small hands, larger grips for bigger hands. z Allow enough work space for the largest hands. Body size z Allow enough space at the workstation for the largest worker. z z
Tungkai bawah z z
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Kursi terlalu dalam akan menekan lutut Kursi terlalu tinggi akan menekan bagian bawah belakang tungkai atas Sandaran kaki, bila sepatu empuk, empuk, lekuk kaki akan tertekan Timbul kesemutan Pedal kaki yang terlalu dekat/jauh akan menyebabkan sudut normal terlampaui
MengangkatMengangkat-junjung MengangkatMengangkat-junjung benda berat dapat menyebabkan 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 bersamabersama-sama Semerata mungkin, mungkin, jangan terlalu banyak orang sehingga mengganggu, mengganggu, sebaiknya sama tinggi, tinggi, bergerak bersamabersama-samasama-komando, komando, setiap orang pada posisi dan pegangan yang benar
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Basic ergonomic principles z
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It is generally most effective to examine work conditions on a case case--byby-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. The following are a few examples of ergonomic changes which, if implemented, 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, 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 using the same muscles again and again and is usually very boring. Workers and equipment should be positioned so that workers can perform perform their jobs with their upper arms at their sides and with their wrists straight. straight.
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If the workstation is properly designed, the worker should be able able to maintain a correct and comfortable body posture. This is important important because an uncomfortable work posture can cause a variety of problems, such such as: back injury; development or aggravation of RSIs; RSIs; circulatory problems in the legs. The main causes of these problems are: poorly designed seating; standing for long periods; reaching too far; inadequate lighting forcing the worker to get too close to the work. work. The following are some basic ergonomic principles for workstation workstation design. A general rule of thumb is to consider body size information, such as height, when choosing and adjusting workstations. Above all, workstations workstations must be adjusted so that the worker is comfortable.
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Interactions between man and such traditional environmental elements including all tools and equipment pertaining to the work place. z The modern concept: man is to be considered the monitoring link of a manmanmachine environment system. z
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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. z Consideration should be given to the general physical and mental demands of the task, so as not to overload the operator. z
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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 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. z The task should not require excessive mental and muscular effort. z The job should not be so easy that boredom and inattention lead to unnecessary errors and accidents. z
The task of the design engineer and safety professional is to find the happy blend between “easy” easy” and difficult” difficult” jobs. z With very low levels of physiological and psychological stress, performance is also low; as stress increases, however, performance also increases— increases—to a point. z The task is to design jobs that will be centered around optimum performance. z
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Biomechanics— Biomechanics—physical demands Often, the man’ man’s contribution to a system is to provide a countermeasure in the event of system malfunction or component failure. z To do this he must know that a failure has occurred and what to do about it. z
Trigger finger (Definition) z
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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 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 that the most common cause of Carpal Tunnel Syndrome is certain repetitive repetitive finger and thumb 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 nonnonelastic (has no "give") it cannot expand; therefore, the swollen structures press on the Median Nerve, causing the above symptoms.
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 the hand and thumb; difficulty in making a fist; and 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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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 materials such as laundry and paper products • Knitting and sewing Other, less common causes of Carpal Tunnel swelling may include cysts, tumors, fluid retention during pregnancy, arthritis, and wrist fractures.
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. Stretching exercises: exercises: Using one 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 z z z z z
Display atau control untuk kepentingan keamanan kerja Display merupakan input bagi pekerja Dapat berupa display visual, auditori ataupun taktual Display untuk mengecek, mengecek, kuantitatif dan kualitatif Æ menunjukkan bagaimana mesin berfungsi Kesalahan mengartikan informasi dan tidak jelasnya display pada peralatan Æ kesalahan operasi, operasi, kecelakaan
User friendly?
The result is….
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Ergonomics
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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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