Analysis Of Sawmill Workers Through Integration Of Video Observation And RULA Method

(1)

ANALYSIS OF SAWMILL WORKERS THROUGH

INTEGRATION OF VIDEO OBSERVATION AND RULA

METHOD

MUHAMMAD JAMLI BIN MOHD ALI

(2)

UNIVERSITI TEKNIKAL MALAYSIA MELAKA

ANALYSIS OF SAWMILL WORKERS THROUGH INTEGRATION

OF VIDEO OBSERVATION AND RULA METHOD

Thesis submitted in accordance with the requirements of Universiti Teknikal

Malaysia Melaka for the Bachelor Degree of Manufacturing Engineering in

Manufacturing Management

By

MUHAMMAD JAMLI BIN MOHD ALI

Faculty of Manufacturing Engineering

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UTeM Library (Pind.1/2007)

UNIVERSITI TEKNIKAL MALAYSIA MELAKA

BORANG PENGESAHAN STATUS PROJEK*

JUDUL: Analysis of Sawmill Workers Through Integration of Video Observation and RULA Method.

SESI PENGAJIAN: 4/2

Saya : MUHAMMAD JAMLI BIN MOHD ALI

mengaku membenarkan projek (PSM/Sarjana/Doktor Falsafah) ini disimpan di Perpustakaan Universiti Teknikal Malaysia Melaka (UTeM) dengan syarat-syarat kegunaan seperti berikut:

1. Projek adalah hak milik Universiti Teknikal Malaysia Melaka .

2. Perpustakaan Universiti Teknikal Malaysia Melaka dibenarkan membuat salinan untuk tujuan pengajian sahaja.

3. Perpustakaan dibenarkan membuat salinan projek ini sebagai bahan pertukaran antara institusi pengajian tinggi.

4. **Sila tandakan (√)

SULIT

TERHAD

√ TIDAK TERHAD

(Mengandungi maklumat yang berdarjah keselamatan atau kepentingan Malaysia yang termaktub di dalam AKTA RAHSIA RASMI 1972)

(Mengandungi maklumat TERHAD yang telah ditentukan oleh organisasi/badan di mana penyelidikan dijalankan)

(TANDATANGAN PENULIS)

Alamat Tetap:

No 6, Jalan Masjid, Kg Kerayong, 28200, Bera,

Pahang Darul Makmur.

Tarikh: 25/03/08

Disahkan oleh:

(TANDATANGAN PENYELIA)

Cop Rasmi:

Tarikh: _______________________

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FAKULTI KEJURUTERAAN PEMBUATAN

Rujukan Kami (Our Ref) : 25 Mac 2008

Rujukan Tuan (Your Ref):

Pustakawan

Perpustakawan Universiti Teknikal Malaysia, UTeM, Ayer Keroh,

MELAKA.

Saudara,

PENGKELASAN TESIS SEBAGAI SULIT/TERHAD

- TESIS SARJANA MUDA KEJURUTERAAN PEMBUATAN (PENGURUSAN PEMBUATAN): MUHAMMAD JAMLI BIN MOHD ALI

TAJUK: ASSESSMENT OF WORKING POSTURE OF SAWMILL WORKERS THROUGH INTEGRATION OF VIDEO OBSERVATION AND RULA METHOD.

Sukacita dimaklumkan bahawa tesis yang tersebut di atas bertajuk

“ASSESSMENT OF WORKING POSTURE OF SAWMILL WORKERS THROUGH

INTEGRATION OF VIDEO OBSERVATION AND RULA METHOD” mohon dikelaskan

sebagai terhad untuk tempoh lima (5) tahun dari tarikh surat ini memandangkan ia mempunyai nilai dan potensi untuk dikomersialkan di masa hadapan.

Sekian dimaklumkan. Terima kasih.

“BERKHIDMAT UNTUK NEGARA KERANA ALLAH”

Yang benar,

ISA BIN HALIM

Pensyarah,

Fakulti Kejuruteraan Pembuatan

(Penyelia Utama)

UNIVERSITI TEKNIKAL MALAYSIA MELAKA

Karung Berkunci 1200, Ayer Keroh, 75450 Melaka

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APPROVAL

This thesis submitted to the senate of UTeM and has been accepted as partial fulfillment

of the requirements for the degree of Bachelor Manufacturing Engineering

(Manufacturing Management) with Honours. The members of the supervisory committee

are as follow:

Signature : ...

Supervisor : Mr. Isa bin Halim

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DECLARATION

I hereby, declared this thesis entitled “Assessment of Working Posture of Sawmill Workers Through Integration Of Video Observations and RULA Method” is the results

of my own research

except as cited in references.

Signature : ………

Author’s Name : Muhammad Jamli Bin Mohd Ali

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i

ABSTRACT

This study discusses the assessment of working posture of sawmill workers while they

performing the jobs at their workstation. In sawmill industry, the workers require to

perform various activities such as lifting, pulling, pushing, holding and blocking timber

products. To carry out such activities, they have to perform forward bending or side

bending of their body part especially the upper body. These working postures might be

negatively influencing workers’ health. In recognition the importance of working posture,

the study is conducted to assess working posture of workers while they performing their

jobs in existing workstation and propose appropriate solutions to improve their working

posture. To achieve the objectives, this study starts with an observation at sawmill

industry by using a video camera. Data collection process is done by capturing the

working posture images, having personal interview and distribute a questionnaire. The

captured working posture images were analyzed by RULA analysis incorporated in

CATIA software. To improve the working posture, engineering control method is applied

where the existing workstations were redesigned and analyzed through CATIA software.

The effectiveness of the proposed design is determined by comparing the RULA score of

existing workstation over proposed design. Based on the comparison, the author

concluded that the proposed design of workstations enable workers to perform their job

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ABSTRAK

Kajian ini membincangkan tentang penilaian postur bekerja bagi pekerja kilang balak

semasa mereka melakukan kerja di tempat kerja mereka. Di dalam industri pembalakan,

pekerja kilang balak perlu melakukan pelbagai aktiviti seperti mengangkat, menarik,

menolak, memegang dan menahan produk yang dihasilkan dari kayu balak. Untuk

melakukan aktiviti-aktiviti tersebut, mereka iaitu pekerja-pekerja balak tadi terpaksa

menunduk atau membengkokkan anggota badan mereka terutamanya bahagian atas

badan. Justeru itu, postur yang diamalkan oleh pekerja balak mungkin mempengaruhi dan

memberi kesan negatif pada kesihatan pekerja balak. Atas kesedaran akan pentingnya

postur pekerjaan pada pekerja balak, kajian ini telah dijalankan untuk mengkaji postur

pekerja semasa mereka bekerja di tempat kerja dan satu cadangan yang sesuai akan

diusulkan untuk memperbaiki postur bekerja mereka semasa bekerja di kawasan kerja

mereka. Kajian ini mempunyai beberapa objektif yang perlu dipenuhi. Untuk mencapai

objektif-objektif kajian, satu pemerhatian telah dilakukan di kilang balak dengan

menggunakan video kamera. Proses pengumpulan data telah dilaksanakan dengan

mengambil gambar postur pekerja , mengadakan sesi temubual dan mengedarkan soal

selidik di kilang berkenaan. Gambar yang dirakam kemudiannya akan dianalisa

menggunakan RULA analisis yang disediakan di dalam perisian CATIA. Untuk

memperbaiki postur pekerja yang telah dipilih untuk dikaji dalam kajian ini, kaedah

kawalan kejuruteraan telah diaplikasikan dimana tempat kerja yang sedia ada

direkabentuk semula dan dianalisa menggunakan perisian CATIA. Seterusnya,

keberkesanan rekabentuk yang diusul akan ditentukan dengan membandingkan skor

RULA bagi tempat kerja sedia ada dengan rekabentuk tempat kerja yang dicadangkan.

Berdasarkan keputusan perbandingan yang telah dilakukan, penulis merumuskan bahawa

rekabentuk yang dicadangkan membolehkan pekerja-pekerja balak melakukan kerja

mereka dalam keadaan postur yang selamat dan ternyata dibuktikan melalui keputusan

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DEDICATION

For My Beloved Parents:

Mohd Ali bin Abu Bakar

Salmiah binti Arshad

My Beloved Siblings:

Nor Salasiah binti Mohd Ali

Noor Zaikiah binti Mohd Ali

My Respected Supervisor:

Mr Isa bin Halim

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ACKNOWLEDGEMENT

Firstly, Alhamdullillah. Thank to Allah the Almighty God S.W.T for giving me

the opportunity and time to complete my thesis project for final year. Since doing this

thesis, I have an opportunity to learn something new and get extra knowledge on how to

conduct a project in industrial field.

I would like to thank my respected supervisor, Mr. Isa bin Halim for his guidance

and comments on how to developed an ergonomics assessment in real industrial field. He

have encouraged and inspired me to complete my thesis on time and very much thank

you for Mr. Isa for all his guidance and support to me. I also would like to thank my

parents for giving me the moral support and inspired me for all the hard time. Lastly, I

would like to thank all the lectures and my fellow friends whose help me a lot in

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v

LIST OF FIGURES

1.1 Hierarchy of study scope and focus...5

1.2 Structure of overall report...8

2.1 Sitting working posture...10

2.2 Standing working posture...10

2.3 Forward bending posture...11

2.4 Saw blades...22

2.5 Saw filers benching a double cut saw...23

2.6 Side bending posture...26

2.7 Forward bending posture...27

2.8 Excessive forward bending posture...27

3.1 Angle of working posture ...42

3.2 Angle of working posture ...42

3.3 Dimension part of anthropometric data measurement...43

3.4 RULA Analysis dialog box...45

3.5 Display button to switch the mode...47

3.6 Advance mode score display...47

3.7 Summarization of methodology ...50

4.1 Raw timbers area...52

4.2 Forklift used to transfer the raw timbers to the production site...52

4.3 Pulling posture associated with extreme manual load lifting...55

4.4 The worker has to bend to remove the timber during cutting process...57

4.5 Process flow to cut a timber...57

4.6 Install and tightening the saw blades...57

4.7 Rolling the timber to the cutter machine...57

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4.9 Worker bends to arrange sawn timbers on the platform...58

4.10 Worker twists his waist to placing the sawn timbers...58

4.11 Flow Chart of Sawn Timbers Arrangement Process...60

4.12 Take the sawn timbers from table...60

4.13 Put the sawn timber on the platform according to it dimensional size...60

4.14 Arranging the sawn timber...60

5.1 Current workstation design for Case Study 1...62

5.2 RULA Analysis Result (Right Side/Case Study 1)...63

5.3 RULA Analysis Result (Left Side/Case Study 1)...63

5.4 Current Workstation Design for Case Study...64

5.5 RULA Analysis Result (Right Side/Case Study 2)...65

5.6 Cart Design...66

5.7 Specification and proposed material of cart design...68

5.8 RULA Analysis Result (Right Side /Case Study 2)...69

5.9 RULA Analysis Result (Left Side /Case Study 2)...69

5.10 Three Stages Platform...70

5.11 RULA Analysis Result (Right Side /Case Study 1)...72

5.12 RULA Analysis Result (Left Side /Case Study 1)...72

5.13 Comparison Chart of RULA Score (Left and Right / Case Study 1)...74

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LIST OF TABLES

2.1 Accident Register Records...15

3.1 Specification of Video Camera...41

3.2 Anthropometry Data of Sawmill Workers...44

4.1 Description of Cutting Process...56

4.2 Description of Sawn Timber Arranging Process...59

5.1 Tables of RULA Analysis Score Results for Case Study 1...74

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LIST OF ABBREVIATIONS

BCPE Board of Certification for Professional Ergonomists

BLS Bureau of Labor Statistics

CAD Computer Aided Design Software

CAE Computer Aided Engineering

CAM Computer Aided Manufacturing

CMOS Complementary Metal Oxide Semiconductor

COHFE Center of Human Factor Ergonomics

CTD Cumulative Trauma Disorder

EMG Electromyography

ILO International Labour Organization

IBM International Business Machine

ISO International Organisation of Standardisation

JPEG Joint Photographic Experts Group

LBP Low Back Pain

MSD Musculoskeletal Disorder

NIOSH National Institute of Safety and Health

OSHA Occupational Safety and Health

OWAS Ovako Working Posture Analysis System

REBA Rapid Entire Body Assessment

RULA Rapid Upper Limb Assessment

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WMSD Work Related Musculoskeletal Disorder

WRULD Work Related Upper Limb Disorder

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1

CHAPTER 1 INTRODUCTION

This chapter provides information regarding to background of study, problem

statements, and objectives of study. Besides, this chapter also describes the scope and

limitation of study, potential benefits from the study that may significant to the

personal, authorities, or related organizations. The outline of conducted study also

presented in this chapter

1.1 Background of Study.

Sawmill industry is an enormous industry not only in Malaysia, but also in the

international level. Countries that have a wide area of forest and received a constant

rain distribution per year mainly become the role player in this industry due to the

unlimited source of timber plant. Currently, Malaysia is the largest exporters of logs,

sawntimber, and the main exporter of wood-based product such as plywood, wooden

furniture and builders’ carpentry in Asian region. Providing a job to more than 300,000

workers, the Malaysian sawmill industry had grown rapidly and significantly play a

major role to the development of socioeconomic sector in Peninsular Malaysia, Sabah

and also in Sarawak (Anon, 2007a).

Application of advanced and diverse technology machinery is vital to this type of

industry. Sawing or cutting machine application is the major type of machine used,

either automatic or manual operations. Besides using a machine to cut or process the

logs, human workforce is also needed to run the machines and perform the other job in

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2

lifting, pushing and removing a processed timber, handling a manual device such as

saw blades, pushing trolley, and pulling a pulleys to remove the timber are the example

of manual task perform by the workers repetitively and done everyday in the sawmill

industry (WorkSafe, 2005).

These activities require the workers to apply a specific posture to carry out the job or

can be termed as working posture. Working posture is one of the ergonomics issues

under the industrial ergonomics discipline. Unsafe working posture while performing

job activities not only uncomfortable to the workers, but also exposed the workers to a

musculoskeletal disorders (MSD). The manual task activities perform by the workers is

believed as a major contributor to the occupational injuries in the sawmill industry

(Edwin M., 2003). Workers bending or twisting repetitively while performing their job

associated with a great risk of MSD. MSD include sprains, strains, inflammation,

degeneration, tears, pinched nerves or blood vessels, bone splintering and stress

fractures. Neck, shoulder, wrist, and low back are the common body part that has a

great potential to sustain injury or the MSD due to an awkward working posture such as

excessive forward bending to pick up a load repetitively as what the sawmill floor

workers done everyday.

In recognition of the importance of working posture issues, ergonomics assessment

needs to be carried out in order to establish safe working posture. Rapid Upper Limb

Assessment (RULA) is selected as a tool to asses and analyzes the risk factors of the

working posture as this tool is postural analysis software oriented. By using a video

observation, an image of unsafe working posture is recorded and analyzed using

RULA. The unsafe working posture that declared below the safe standard will be

improved through scope of engineering controls which is by redesigning the current

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3 1.2 Problem Statements.

Sawmill industry is among the manufacturing industry that applying a working

environment which workers are requires to apply high forces, unsafe working posture,

manual handling operations, and repetitive motions in performing job task. Unsafe

working posture such as bending, twisting, pushing, and lifting a heavy load are the

major contributors to the potential occupational injuries among an industrial workers.

In sawmill industry, workers are highly expose to the occupational injuries due to the

job activities that require them to deal with the logs and processed timber. Manual

handling device and a workstation design of workers to perform their job also

contribute to the occupational injuries. The design of workstation also can be a

significant contributor to the workers to have a musculoskeletal disorder and other

occupational injuries. It is known that work-related musculoskeletal disorders are

caused by multifactor operations of various risk factors. Safe working posture is

considered as vital contributor to feasible occupational health in most industries in

Malaysia. Through feasible occupational health, the productivity and quality of

industries can be increased. Among these, the association of these risk factors with pain

symptoms and work-related musculoskeletal disorders has been reported in many

studies in all typical manufacturing settings (Bernard, 1997).

Following are problems which related to the MSD injuries among the sawmill industry

workers:

a) The sawmill industry is known to have a high level of manual handling, with

tasks often involving high loads/forces, awkward postures, and repetitive

movements; some of the key risk factors for MSDs (Tappin D. et. al, 2003).

b) At least 6500 new claims occurred during the four year period of the review,

equating to approximately 3250 new injury claims for Log Sawmilling and

Timber Resawing and Dressing. Awkward posture is among the injury cause

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4 1.3 Objectives of Study.

In recognition the importance of working posture in sawmill industry, this study is

conducted to achieve following objectives:

a) To record and assess current working posture adopted by the workers in their

usual workstation.

Working postures of workers will be recorded using a video camcorder.

Recorded working posture will be evaluated using Rapid Upper Limb

Assessment (RULA) applied as a tool to assess the risk factors of posture, static

muscle contraction, repetitive motion, and force relative to a specific job by

referring to the captured image.

b) To redesign the current workstation in order to improve working posture.

One of the proposed ergonomics intervention control methods which are in the

scope of engineering control is applied in this study. The current workstation

will be observed and redesign by using the Computer Aided Design (CAD)

software which is CATIA software for this study.

c) To evaluate the effectiveness of the proposed workstation design.

Comparison method is used to achieve this objective. The working posture of

workers while performing their job at current and proposed workstation is

analyzed by using RULA. The RULA result will determine the effectiveness of

proposed workstation design in term of improvement of the workers working

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5 1.4 Scope and Limitation.

Basically, this study focuses in analyzing the working posture of sawmill industry

workers by applying the integration of video observation and Rapid Upper Limb

Assessment (RULA) associated with CATIA v5R12. Workers of sawmill industry was

selected due to their job activities that requires them to push, twist, bend, lifts, and

handling with the manual device such as trolleys, thus may lead to a MSD crisis to the

workers. A workstation design also will be proposed as a solution for improvement of

the current working posture. The design of the proposed workstation is depend on the

company consideration as it’s only a proposed solution. The limitation for this study is

the obtained results only applicable for the selected working posture in this study and

cannot be apply for other posture due to a different posture have different body part

angle. This study also only concern in a physical ergonomics which focuses on

biomechanical characteristic, human anatomical and physiological as it related to

[image:23.612.122.520.405.652.2]

physical activities such as working posture that will be investigated in this study.

Figure 1.1 shows the hierarchy of focus and scope of this study:

Working Posture

Workstation

Manual Activities (pushing, pulling, lifting, etc)

Sawmill Industry 1st

2nd

3rd

4th

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6 1.5 Potential Benefits of Study.

This study may offer potential benefits to the following parties:

a) Sawmill industry.

 Able to promote and enhance ergonomics awareness in sawmill industry to

minimize occupational injuries in this industry.

 The findings of the study can be used as a guideline for the industry owner to

design a workstation.

b) University or educational organizations.

 As a reference for academic studies related to MSDs issue and working posture

analysis in industrial fields.

 As a reference for future studies on ergonomic workstation design and

improvement of working posture of industrial workers.

c) Authorization party.

 This study can be used by the National Institute for Occupational Safety and

Health (NIOSH) as a guideline and references to prevent MSD injuries among

sawmill industry workers.

 A document to support the effort of NIOSH in promoting a safe working

condition among the industrial workers.

d) Students.

 The study may improve the students’ ability and skills in developed a case study

and enhance their soft skills.

e) Country.

 Reduce the occupational injuries among the industrial workers and create a

healthy working environment, thus boost up the productivity and economic

Analysis Of Sawmill Workers Through Integration Of Video Observation And RULA Method

ANALYSIS OF SAWMILL WORKERS THROUGH

INTEGRATION OF VIDEO OBSERVATION AND RULA

METHOD

MUHAMMAD JAMLI BIN MOHD ALI

UNIVERSITI TEKNIKAL MALAYSIA MELAKA

ANALYSIS OF SAWMILL WORKERS THROUGH INTEGRATION

OF VIDEO OBSERVATION AND RULA METHOD

MUHAMMAD JAMLI BIN MOHD ALI

UNIVERSITI TEKNIKAL MALAYSIA MELAKA

APPROVAL

DECLARATION

ABSTRACT

ABSTRAK

DEDICATION

ACKNOWLEDGEMENT

TABLE OF CONTENTS

LIST OF FIGURES

LIST OF TABLES

LIST OF ABBREVIATIONS

CHAPTER 1

INTRODUCTION