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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