ANALYSIS OF OBSERVATIONAL TECHNIQUES FOR ASSESSING WORKING POSTURAL LOADS IN SMALL AND MEDIUM ENTERPRISES (SMEs) INDUSTRY MUHAMMAD HAZIM BIN HUSSIN A thesis submitted in fulfilment of the requirement for the award of the Degree of Master of Mechanical Engineering Faculty of Mechanical and Manufacturing Engineering Universiti Tun Hussein Onn Malaysia JANUARY 201 5
ABSTRACT Small Medium Enterprise (SMEs) products industries consist of various job loads that involved handling process from raw food part to the packaging as end products. In this study, the working environment of potato tubers processing in rural area was used for the study assessment. However, this kind of job requires high force job load and awkward postures thus contribute to cause Musculoskeletal Disorder (MSDs). This field of study is to assess the risk of manual handling activities by comparing using the observational techniques and Cornell Musculoskeletal Discomfort Questionnaire (CMDQ) tool. The CMDQ tool was applied to study the prevalence of WMSDs by through interview session and direct observation using digital camera during the visit. The Rapid Upper Limb assessment (RULA) and The Rapid Entire Body Assessment (REBA) methods used and categorised in this study. The collected data analysed and appropriate recommendation for ergonomic intervention will be proposed to reduce the risk level of the task. To determine the effectiveness of the proposed solution, table of comparison using RULA and REBA with marks evaluation were conducted. With associated to CMDQ tools, the results show that the most body discomfort areas were recorded in the shoulder about 80 %, followed by lower back (75%), forearm (75%), wrist (75%), upper arm (70%), thigh (45 %), knee (40%) foot (35%) and lower leg (20%). For RULA and REBA score mostly they are rated in ten (10) and (7) score, meaning that the higher the grand score the high recommendation and investigation need to be done to prevent any injury. Chi-square analysis revealed a significant association between the number of person complains pain in the shoulder, lower back, forearm and wrist and the RULAfREBA score grand score Ip < 0.05). Based on the result obtained so far, it is shows h t there is a risk on the working posture task 1 (cutting raw part potato tubers) and task 2 (sliced potato tuber with machine). This study also includes on minimizing and eliminating the risk of work related to entire body disorder exposure.
ABSTRAK Small and Medium Enterprises (SMEs) industri rnelibatkan pelbagai jenis cara kerja yang bermula dari proses asas sehingga penghasilan sesebuah produk. Dalam kajian ini, industri kerepek di kawasan kampung dianalisa untuk penilaian risiko ketidakselesaan yang dihadapi oleh setiap pekerja di kilang tersebut. Justeru, bidang kerja ini memerlukan postur janggal dan daya kerja yang tinggi dalam pengendalian yang boleh mengakibatkan penyakit Musculoskeletal Disorders (MSDs). Tujuan kajian ini dilaksanakan adalah untuk menilai risiko aktiviti rnanual handling di pusat pemprosesan kerepek menggunakan kaedah perbandingan pemerhatian dan Cornell Musco2oskeletaE Disorder Questionnaire (CMDQ). Kaedah CMDQ telah menjadi kelaziman untuk kajian WMSDs melalui sesi temubual dan pemerhatian langsung menggunakan sebuah kamera digitai. The Rapid Upper Limb assessment method (RULA) dan The Rapid Entire Body Assessment Method (REBA) telah digunakan seterusnya dikategorikan berdasarkan penilaian menggunakan kaedah tersebut. Keputusan kajian yang diperoleh menunjukkan bahagian ketidakselesaan paling tinggi telah direkodkan pada bahagian bahu badan sebanyak 80% dan diikuti oleh bahagian bawah belakang badan sebanyak 75%, ini diikuti bahagian pergelangan tangan 75%, bahagian lengan 75%, pergelangan tangan 75% dan bahagian atas tangan (70%). Keputusan akhir penilaian RULA dan REBA pula diklafisikasikan melalui jumlah keseluruhan markah postur pada angka 10 dan 7. Nilai ini bermakna semakin tinggi nilai jumlah keseluruhan markah maka cadangan dan penyiasatan perlu dilakukan segera bagi mengelakkan sebarang kecederaan. Analisa Chi-square juga untuk membuktikan pertalian diantara nilai RUL,A/REBA terhadap ketidakselesaan pada bahu, bahagian bawah belakang badan dan tangan (p~0.05). Data yang telah dilsumpulkan, dianalisis dan penambahabaikan ergonornik dicadang untuk mengurangban risiko membabitkan keselesaan pekerja. Bagi mengenal pasti keberkesanan penambahbaikan, carta perbandingan digunakan mengikut kaedah markah yang telah ditetapkan.
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