Integrating iso 9001 2015 standard and lean six sigma tools into a quality management system the case study of a furniture manufacturing company

VIETNAM NATIONAL UNIVERSITY HO CHI MINH CITY
HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY

PHAN LE MINH PHUONG

INTEGRATING ISO 9001:2015 STANDARD AND LEAN SIX
SIGMA TOOLS INTO A QUALITY MANAGEMENT
SYSTEM. THE CASE STUDY OF A FURNITURE
MANUFACTURING COMPANY.

Major:
Industrial Engineering
Major code: 8520117

MASTER’S THESIS

HO CHI MINH CITY, July 2023


THIS THESIS IS COMPLETED AT
HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY – VNU-HCM

Supervisor: Dr. Nguyễn Vạng Phúc Nguyên
Examiner 1: Dr. Lê Đức Đạo
Examiner 2: Dr. Đỗ Thành Lƣu
This master’s thesis is defended at HCM City University of Technology, VNUHCM City on 8th July 2023.
Master’s Thesis Committee:
1. Chairman: Assoc. Prof. Dr. Đỗ Ngọc Hiền
2. Secretary: Dr. Lê Song Thanh Quỳnh
3. Reviewer 1: Dr. Lê Đức Đạo
4. Reviewer 2: Dr. Đỗ Thành Lƣu

5. Member: Dr. Trần Quỳnh Lê
Approval of the Chairman of Master’s Thesis Committee and Dean of Faculty
of Mechanical Engineering after the thesis being corrected (If any).

CHAIRMAN OF THESIS COMMITTEE

HEAD OF FACULTY OF
MECHANICAL ENGINEERING


VIETNAM NATIONAL UNIVERSITY HO CHIMINH CITY
HOCHIMINH CITY UNIVERSITY OF TECHNOLOGY

SOCIALIST REPUBLIC OF VIETNAM
Independence – Freedom - Happiness

THE TASK SHEET OF MASTER’S THESIS
Full name
: PHAN LÊ MINH PHƢƠNG
2170119
Date of birth : 18/01/1982
Major
: Industrial Engineering
8520117
I.

Student ID

:

Place of birth : Gia Lai
Major ID
:

THESIS TITLE:
Integrating ISO 9001:2015 Standard and Lean Six Sigma Tools into a Quality Management
System. The Case Study of a Furniture Manufacturing Company (Tích hợp Tiêu chuẩn ISO
9001:2015 và các cơng cụ Lean Six Sigma vào Hệ thống quản lý chất lƣợng của công ty
sản xuất đồ gỗ nội thất)

II.

TASKS AND CONTENTS:

Create a concept map for integrating the quality management system of a furniture
manufacturing company with the ISO 9001:2015 Standard and Lean Six Sigma
methodology.
Establish a methodology to implement the integrated system of ISO 9001:2015 and Lean
Six Sigma tools into the furniture manufacturing company's quality management system.

III. THESIS START DAY: 06/02/2023
IV. THESIS COMPLETION DAY: 11/06/2023
V. SUPERVISOR: Dr. Nguyễn Vạng Phúc Nguyên
Ho Chi Minh City, date . . . . month .. . . year 2023.
SUPERVISOR
(Full name and signature)

HEAD OF DEPARTMENT
(Full name and signature)

DEAN OF FACULTY OF MECHANICAL ENGINEERING
(Full name and signature)

i


ACKNOWLEDGEMENTS
Firstly, I would like to express my sincere gratitude to my thesis advisor. Without his
invaluable help and dedicated involvement at every step of the process, this thesis
would not have been possible.
Secondly, I would like to extend my heartfelt thanks to all the teachers in the
Department of Industrial Engineering who have enthusiastically imparted a wealth of
knowledge to me during these two years.
Lastly, and most importantly, I would like to express my deepest appreciation to my
husband and my two children for their unwavering support and assistance throughout
my journey of studying and writing this thesis. I take full responsibility for any errors
or inadequacies that may be present in this work.

ii


ABSTRACT
ISO 9001:2015 and Lean Six Sigma methodologies are widely adopted by companies
worldwide nowadays. While there have been studies integrating these approaches into
a single framework, they have generally remained at a generic level without delving
into specific sectors. In Vietnam, there is a growing need to implement ISO
9001:2015 and Lean Six Sigma as a means to assess a company's readiness to join the
global supply chain. However, many small and medium Vietnamese companies are
facing difficulties in applying the above systems due to the lack of available guidance
to facilitate the integration of these practices.

This research focuses on developing an integrated system of ISO 9001:2015 and Lean
Six Sigma tailored specifically for the furniture manufacturing industry. The aim is to
enhance the industry's capabilities and improve its competitiveness in the market.
Building upon previous integration frameworks, this research provides a detailed
examination of each ISO 9001 requirement and identifies the appropriate processes
and Lean Six Sigma tools to complement them.
The proposed integrated system has undergone review and been accepted for
implementation at a furniture manufacturing company. It is specifically designed for
the furniture manufacturing industry, enabling the application of ISO 9001:2015 and
Lean Six Sigma with greater ease and efficiency. It also reduces the risk of
misapplying ISO standards and Lean Six Sigma tools.
This tailored integrated concept map can be further developed and extended to other
leading industries in Vietnam, such as textiles, footwear, and food processing. By
doing so, it will contribute to improving the competitiveness of Vietnamese
companies in the market.

iii


TÓM TẮT LUẬN VĂN THẠC SĨ
Hiện nay, hệ thống quản lý chất lượng theo tiêu chuẩn ISO 9001:2015 và phương
pháp Lean Six Sigma được các cơng ty trên tồn thế giới áp dụng rộng rãi. Mặc dù đã
có những nghiên cứu để tích hợp các cách tiếp cận này thành một hệ thống duy nhất,
nhưng chúng vẫn dừng ở các mơ hình chung chung mà khơng đi sâu vào bất cứ lĩnh
vực cụ thể nào. Tại Việt Nam, nhu cầu triển khai ISO 9001:2015 và Lean Six Sigma
như một cách thức để đánh giá mức độ sẵn sàng tham gia chuỗi cung ứng tồn cầu
của một cơng ty ngày càng tăng. Tuy nhiên, nhiều công ty vừa và nhỏ của Việt Nam
đang gặp khó khăn trong việc áp dụng các hệ thống trên do thiếu các tài liệu hướng
dẫn thực hiện tích cả tiêu chuẩn ISO 9001:2015 và các cơng cụ Lean Six Sigma vào
hệ thống quản lý hiện có của công ty.

Nghiên cứu này tập trung vào việc phát triển một hệ thống tích hợp ISO 9001:2015 và
Lean Six Sigma được thiết kế riêng cho ngành sản xuất đồ nội thất. Mục đích là để
tăng cường khả năng và nâng cao khả năng cạnh tranh của nó trên thị trường. Dựa
trên các mơ hình tích hợp đã đề xuất trước đó, nghiên cứu này thực hiện xem xét chi
tiết về từng yêu cầu của ISO 9001 và xác định các quy trình và cơng cụ Lean Six
Sigma thích hợp đáp ứng các yêu cầu của tiêu chuẩn, qua đó từng bước hình thành hệ
thống quản lý tích hợp.
Hệ thống tích hợp đề xuất đã được xem xét và được chấp nhận để triển khai tại một
công ty sản xuất đồ nội thất. Hệ thống được thiết kế đặc biệt cho ngành sản xuất đồ
nội thất, cho phép áp dụng ISO 9001:2015 và Lean Six Sigma một cách dễ dàng và
hiệu quả hơn, giúp làm giảm nguy cơ áp dụng sai các tiêu chuẩn ISO và các công cụ
Lean Six Sigma.
Mơ hình khái niệm tích hợp phù hợp được hình thành trong nghiên cứu có thể được
tiếp tục phát triển và mở rộng sang các ngành công nghiệp hàng đầu khác ở Việt
Nam, chẳng hạn như dệt may, da giày và chế biến thực phẩm. Qua đó sẽ góp phần
nâng cao năng lực cạnh tranh của các doanh nghiệp Việt Nam trên thị trường.

iv


THE COMMITMENT OF THE THESIS’ AUTHOR
I hereby declare that the master’s thesis titled ―Integrating ISO 9001:2015 Standard
and Lean Six Sigma Tools into a Quality Management System. The Case Study of a
Furniture Manufacturing Company‖ is the research work that I have personally
undertaken and completed. I received scientific guidance from Dr. Nguyen Vang Phuc
Nguyen at Ho Chi Minh City University of Technology to support and guide me in
writing my thesis. The results of this study have not been published in any other
separate studies. I have followed the appropriate rules and guidelines when
incorporating results and quotations from other authors' documents into my essay. The
citations and references from books, newspapers, and websites have been presented in

accordance with the reference list of the thesis.
Author

Phan Le Minh Phuong

v


TABLE OF CONTENTS
Chapter 1. OVERVIEW ............................................................................................................... 1
1.1 Introduction ............................................................................................................................. 1
1.2 Problem description ................................................................................................................ 1
1.3 Research goal ........................................................................................................................... 2
1.4 Research question .................................................................................................................. 2
1.5 Research objective .................................................................................................................. 2
1.6 Research structure .................................................................................................................. 3
Chapter 2. LITERATURE REVIEW ......................................................................................... 4
2.1 ISO 9001:2015 Quality management system Requirements ............................................... 4
2.2 Lean & Six Sigma methodology............................................................................................. 7
2.3 The integration between ISO 9001:2015 and Lean Sigma .................................................. 9
Chapter 3. INTRODUCTION OF RESEARCH SUBJECT .................................................. 13
3.1 Introduction of Minh Duong Furniture Corporation ....................................................... 13
3.1.1

History ........................................................................................................................ 13

3.1.2

Company’s achievements: ........................................................................................ 13

3.1.3

Company organization .............................................................................................. 14

3.2 Minh Duong’s Quality management system....................................................................... 14
3.2.1

Current documentation system ................................................................................ 14

3.2.2

Gap analysis ............................................................................................................... 16

Chapter 4. METHOD ................................................................................................................. 21
4.1 ISO 9001:2015 Standard and Lean Six Sigma Methodology Integration Model............ 21
4.2 Approach ISO 9001:2015 Requirements and Applicable Tools ....................................... 22
4.2.1

ISO 9001:2015 Requirements ................................................................................... 22

4.2.2........................................................................................................................................... 24
4.2.3

Lean Six Sigma Tools and Strategic Tools .............................................................. 24
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Chapter 5. ANALYSIS OF ISO 9001 REQUIREMENTS AND SUGGESTED LEAN
SIX SIGMA TOOLS ON QUALITY MANAGEMENT OPERATIONS ............................. 33
5.1 Context of the organization (ISO Clause 4)........................................................................ 33

5.2 Leadership (ISO Clause 5) ................................................................................................... 37
5.3 Planning (ISO Clause 6) ....................................................................................................... 39
5.4 Support (ISO Clause 7) ........................................................................................................ 44
5.5 Operations (ISO Clause 8) ................................................................................................... 46
5.5.1

Operational planning and control (Clause 8.1)....................................................... 46

5.5.2

Requirements for products and services (Clause 8.2) ............................................ 47

5.5.3

Control of externally provided processes, products, and services (8.4)................ 47

5.5.4

Production and Service provision (ISO Clause 8.5) ............................................... 48

5.5.5

Release of products and services (ISO Clause 8.6) ................................................. 51

5.5.6

Control of nonconforming outputs (8.7) .................................................................. 51

5.6 Performance evaluation (ISO Clause 9) ............................................................................. 51
5.6.1

Monitoring, measurement, analysis, and evaluation (9.1) ..................................... 51

5.6.2

Internal audit (ISO Clause 9.2) ................................................................................ 53

5.6.3

Management review (ISO Clause 9.3) ..................................................................... 54

5.7 Improvement (ISO Clause 10) ............................................................................................. 55
5.7.1

General (ISO Clause 10.1) ........................................................................................ 55

5.7.2

Nonconformity and corrective action (ISO Clause 10.2) ....................................... 55

5.7.3

Continual improvement (ISO Clause 10.3) ............................................................. 57

Chapter 6. A PROPOSED DESIGN of integrated QMS and LSS ......................................... 59
6.1 Propose the Integration Approaches of ISO 9001:2015 and Lean Six Sigma
methodology into Minh Duong’s quality management system. .............................................. 59
6.2 Propose Integrated QMS Process matrix. .......................................................................... 60
6.3 Designation of Operating procedures for the Integrated QMS ........................................ 64
vii

6.3.1

Manufacturing management Process ...................................................................... 64

6.3.2

Facility/Equipment/Tooling management:.............................................................. 78

6.3.3

Labor management.................................................................................................... 80

6.3.4

Material management ............................................................................................... 82

6.3.5

Technical management.............................................................................................. 84

6.3.6

Quality Control .......................................................................................................... 85

6.3.7

Nonconforming product management ..................................................................... 88

6.3.8

Scheduling and Order management ........................................................................ 89

6.3.9

Purchasing and Supplier management .................................................................... 92

6.3.10

Document and Change management ................................................................... 94

6.4 Overall Process metrics ........................................................................................................ 97
Chapter 7. CONCLUSIONS AND RECOMMENDATIONS .............................................. 105
7.1 Conclusions .......................................................................................................................... 105
7.2 Recommendations ............................................................................................................... 105
REFERENCES .......................................................................................................................... 107
VITA........................................................................................................................................... 110

viii


TABLE OF FIGURES

Figure 2.1: Amount of ISO 9001 certified companies .................................................................... 7
Figure 2.2: Development history of Lean & Six Sigma (Perdana, 2008) ....................................... 8
Figure 3.1: Minh Duong organization chart ................................................................................. 14
Figure 3.2: Minh Duong Documentation System ......................................................................... 15
Figure 3.3: Minh Duong process interaction chart ....................................................................... 16
Figure 3.4: Compliance status....................................................................................................... 17

Figure 3.5: Minh Dƣơng KPI monitoring system. ........................................................................ 17
Figure 3.6: Post Painting quality inspection ................................................................................. 19
Figure 4.1: ISO 9001:2015 Standard and Lean Six Sigma Methodology Integration Model ...... 22
Figure 4.2: The structure of ISO 9001:2015 Standards in PDCA Circle...................................... 23
Figure 4.3: Power and Interest Grid .............................................................................................. 25
Figure 4.4: Turtle diagram ............................................................................................................ 28
Figure 5.1: Power and Interest Grid .............................................................................................. 37
Figure 5.2: Quality Policy ............................................................................................................. 38
Figure 5.3: Risks/opportunities management process .................................................................. 41
Figure 5.4: High-level process chart ............................................................................................. 42
Figure 5.5: Quality objectives and Plan ........................................................................................ 44
Figure 5.6: Improvement project prioritiser.................................................................................. 57
Figure 6.1: The Concept map of Proposed Integrated Quality Management System .................. 60
Figure 6.2: Manufacturing process flowchart ............................................................................... 65
Figure 6.3: Manufacturing process flowchart with clouds ........................................................... 66
Figure 6.4: Fishbone diagram ....................................................................................................... 67
Figure 6.5: 5Why analysis ............................................................................................................ 68
Figure 6.6: Containment actions ................................................................................................... 69
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Figure 6.7: Manufacturing process - Turtle diagram .................................................................... 70
Figure 6.8: 3 C Follow Up Chart .................................................................................................. 72
Figure 6.9: Daily/weekly compliance checklist ............................................................................ 72
Figure 6.10: Post painting rework rate .......................................................................................... 76
Figure 6.11: Procedure template ................................................................................................... 77

x

TABLE OF TABLES

Table 2.1: Definition of quality ...................................................................................................... 6
Table 2.2: Summary of research on integrating ISO 9001:2015 and LSS methodology ............... 9
Table 3.1: Quantity of Production output versal Total work in progress ..................................... 19
Table 5.1: PESTLE Analysis ........................................................................................................ 34
Table 5.2: SWOT Analysis ........................................................................................................... 35
Table 5.3: List of interested parties' needs and expectations ........................................................ 36
Table 5.4: Delegation of Authority ............................................................................................... 39
Table 5.5: Organization’s Risks and Opportunities ...................................................................... 40
Table 5.6: Outsourcing process – Requirements and Explanation ............................................... 47
Table 5.7: Control of Production - Requirements and explanations ............................................. 49
Table 5.8: Monitoring, measurement, analysis, and evaluation ................................................... 53
Table 5.9: Internal audit management – process information....................................................... 53
Table 5.10: Internal audit management – process metrics ............................................................ 54
Table 5.11: Internal audit management – process information..................................................... 56
Table 5.12: Internal audit management – process information..................................................... 56
Table 6.1: Propose Integrated QMS Process matrix ..................................................................... 61
Table 6.2: List of applicable ISO 9001 requirements for Manufacturing process........................ 65
Table 6.3: Containment to quickly fix the process. ...................................................................... 68
Table 6.4: Manufacturing process – Competence requirements ................................................... 73
Table 6.5: Manufacturing process metrics .................................................................................... 74
Table 6.6: Manufacturing support process vs. ISO 9001 Requirements ...................................... 77
Table 6.7: Facility / Equipment / Tooling management – process information ........................... 78
Table 6.8: Facility / Equipment / Tooling management – process metrics .................................. 79
Table 6.9: Labor management - process information ................................................................... 80
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Table 6.10: Labor management - process metrics ........................................................................ 81

Table 6.11: Material management – process information ............................................................ 82
Table 6.12: Material management – process metrics.................................................................... 83
Table 6.13: Technical management – process information .......................................................... 84
Table 6.14: Technical management – process metrics ................................................................. 84
Table 6.15: Quality control – Process information ....................................................................... 85
Table 6.16: Quality control – Process metrics .............................................................................. 87
Table 6.17: Nonconforming product management – process information ................................... 88
Table 6.18: Nonconforming product management – process metrics .......................................... 88
Table 6.19: Order management vs. ISO 9001 Requirements ....................................................... 89
Table 6.20: Order management – process information ................................................................. 89
Table 6.21: Order management – process metrics ........................................................................ 91
Table 6.22: Purchasing vs. ISO 9001 Requirements .................................................................... 92
Table 6.23: Purchasing and Supplier management ....................................................................... 92
Table 6.24: Purchasing and Supplier management – process metrics .......................................... 94
Table 6.25: Document and Change management vs. ISO 9001 Requirements ............................ 94
Table 6.26: Document and Change management – process information ..................................... 94
Table 6.27: Document and Change management – process metrics ............................................ 96
Table 6.28: List of prototype operational process ........................................................................ 96
Table 6.29: Overall Process metrics ............................................................................................. 97

xii


LIST OF ABBREVIATIONS

Continuous Improvement

CI

ISO 9001:2015 Standards

ISO 9001

Lean Six Sigma

LSS

Quality management system

QMS

Small and medium enterprises

SMEs

International Organization for Standardization

ISO

British Standard Institution

BSI

Single Minute Exchange Dies

SMED

Work-in-progress

WIP

Non conformity

NC

Non conformity report

NCR

Value Stream Map

VSM

Total preventing maintenance

TPM

Bill of Materials

BOM

Cost of Non-Quality

CONQ

Purchase order

PO

Purchaser request

PR

Request for Quotation

RfQ

Standard Operating Procedures

SOP

Work Instructions

WI

Human Resources

HR

First-Expired, First-Out

FEFO

First-In, First-Out

FIFO

Acceptable Quality Level

AQL

xiii


Overall Equipment Efficiency

OEE

xiv


CHAPTER 1. OVERVIEW
1.1 Introduction
In recent years, Vietnam has been the destination for some world-famous furniture brand names
such as IKEA, and ASHLEY… or huge clients like COSCO, and WALMART... Many furniture
manufacturing companies have attended the supply chain of those famous brand names and
many more want to join the network. Vietnam has the advantage of being a low-cost country
with a large and skillful workforce which is the most prerequisite condition to attract foreign
investors [1]. Not only that, but the government also issues policies to prioritize foreign
investors with many kinds of tax incentives [2]. If Vietnam can maintain those strengths, it is
still the ideal hub for furniture manufacturing for the next decade.
A common difficulty preventing those Vietnamese companies to be accepted into the
world-famous furniture brand supply chains is that they do not have a mature management
system that could assure the consistent quality of products and competitive product cost while
still maintaining social accountability. By the implementation of ISO 9001: 2015 Standard (ISO
9001), a manufacturing company could meet the prerequisite condition to be a subcontractor for
many famous supply chains. ISO 9001 could help to deliver the product with consistent quality
and the application of Lean Six Sigma (LSS) methodology could help tackle the cost-saving
objective. However, even though many companies try to implement both ISO 9001 and adopt
LSS but only a few of them succeed.
1.2 Problem description

Vietnamese Small and Medium Enterprises (SMEs) face difficulties in applying ISO
9001:2015 as well as adopting Lean Six Sigma. The companies have struggled to maintain the
quality system after implementing the ISO and have not been able to explore all of its benefits.
There are three main reasons for this issue. Firstly, the generic features that make ISO 9001 and
LSS applicable to all enterprises, now become a difficulty for Vietnamese companies due to
resource restrictions. The lack of resources with good knowledge and proper skills to deploy
ISO 9001 and LSS leads to a system failure as defined by Iguchi et al. (2015). Secondly, the
1


lack of discipline in the workforce makes it more difficult and costly to implement and maintain
the system as the company must arrange more resources in facilitating, supervising, and auditing
to keep the system working. Thirdly, top management’s mindsets and commitment are crucial
as the employee will shadow the leader’s behavior. In many failed cases, top management was
not taking their role fully [4], [5]. Generally, there are objective difficulties that prevent
Vietnamese SMEs from participating in the supply chains of world-renowned furniture brands
and they need support to be able to move forward. The failures in the implementation of ISO
9001:2015 & adoption of LSS methodology by Vietnamese SMEs make them struggle and fight
hard to be competitive in the market.
There have been various research studies on the integrated systems of ISO 9001:2015
and LSS methodology over the last few years. However, these studies focus on developing
integration frameworks rather than specifically addressing the implementation of the integrated
system for a specific subject in real life.
1.3 Research goal
The thesis goal is to establish a custom-built integrated system between ISO 9001:2015 and
Lean Six Sigma tools at a specific manufacturing company for exploring all possible benefits of
implementing those systems with minimal resources.
1.4 Research question
 What are the suitable models for integrating ISO 9001:2015 & Lean Six Sigma for small
and medium manufacturing companies?

 How to integrate ISO 9001:2015 Standard and Lean Six Sigma Methodology within the
context of applying it to a specific manufacturing company?
1.5 Research objective
The objectives that need to be achieved as a complete sign of this research is below:
 Develop a model for integrating ISO 9001:2015 Standards and Lean Six Sigma
methodology in a furniture manufacturing company.
2


 Design a method for implementing the integrated systems between ISO 9001:2015
Standard and Lean Six Sigma tools into a quality management system of a furniture
manufacturing company.
1.6 Research structure
The thesis is divided into seven chapters. After the Introduction in Chapter 1, The Literature
review in Chapter 2, and The Introduction of the research subject in Chapter 3, the method for
establishing an integrated system is presented in Chapter 4. The proposed integrated system is
in chapter 5 where all measures for the integration are detailed for implementation. The
conclusion and recommendation are discussed in chapter 6 of the thesis. The schedule of tasks
done during the thesis study period is presented in the last chapter.

3


CHAPTER 2. LITERATURE REVIEW
This chapter aims to present a brief discussion of the quality management system ISO
9001:2015 Standard, Lean Six Sigma methodology as well as the integration between ISO
9001:2015 Standard and Lean Six Sigma.
2.1 ISO 9001:2015 Quality management system Requirements
The first term for discussion is Quality. Quality has been defined in several different ways and
there is not any universal definition of quality exists. Reeves & Bednar, (1994) summarized

some popular quality definitions, strengths, and weaknesses in Table 2.1:Definition of quality.
When viewed from a consumer’s perspective, it means meeting or exceeding customer
expectations [7]. According to ISO 9000 Standard, quality is the degree to which a set of
inherent characteristics of an object fulfills requirements [8]. In this research, we use the
definition by ISO 9000 Standard.
Fulfilling customer’s requirements is crucial to the existence of an organization, so there
must be a means to manage quality. That is when the term Quality management system appears.
Compared with many different definitions of quality, QMS are defined quite uniformly. The
Quality management system is composed of all the organization’s policies, procedures, plans,
resources, processes, and delineation of responsibility and authority, all deliberately aimed at
achieving product or service quality levels consistent with customer satisfaction and the
organization’s objectives. When these policies, procedures, plans, and so forth are taken
together, they define how the organization works and how quality is managed [7]. This is also
similar to the definition by ISO that the quality management system is a set of interrelated or
interacting elements of an organization to establish policies and objectives about quality, and
processes to achieve those objectives [8].
ISO 9001 is the most popular quality management system used all over the world, which
was first published in 1987 by International Organization for Standardization (ISO). The
standard was based on the BS 5750 series from British Standard Institution (BSI) [9]. ISO 9001
sets out the criteria for a certified quality management system that can be used by any
organization, large or small, regardless of its field of activity. ISO 9001 Standard employs the
4


process approach, which incorporates the Plan-Do-Check-Act (PDCA) cycle and risk-based
thinking [10]. In the latest version, ISO 9001:2015, its core elements are standardized by Annex
SL, a high-level structure of ISO Standard. This will help companies implement ISO 9001:2015
easily and integrate with other ISO Management Standards [11]. Nowadays, there are over one
million companies and organizations in over 170 countries certified to ISO 9001 [12]. No
organization is required to implement ISO 9001, except some governments or companies

demand their suppliers must be ISO 9001 certified or at least conform to ISO 9001. The
standard defines what organizations have to be complied with but does not dictate how to
do it. Organizations must define the level of conformance by themselves. When an organization
seeks registration, it must look for an accredited registrar firm to verify its conformance to ISO
9001 [7].
In short description, ISO 9001:2015 Standard is an international standard that specifies
requirements for a QMS. Potential benefits to an organization of implementing this standard
are the ability to consistently provide products and services that meet customer and
regulatory requirements, facilitating opportunities to enhance customer satisfaction;
addressing risks and opportunities associated with its context and objectives; the ability to
demonstrate conformity to specified quality management system requirements [10]. Research
by V. Nguyen (2019) shows that the number of Vietnamese enterprises granted ISO 9001
certificates is not high. This certification rate is not only significantly lower than developed
countries but also lower than neighboring countries like Thailand, and Malaysia (Figure
2.1:Amount of ISO 9001 certified companies).
In this thesis, terms and definitions related to the quality management system are used
as defined in the International Standard ISO 9000:2015 Quality management system –
Fundamentals and Vocabulary [8]
 Quality is “the degree to which a set of inherent characteristics of an object fulfills
requirements”.
 Management system is “a set of interrelated or interacting elements of an organization
to establish policies and objectives and processes to achieve those objectives"
 Quality Management System is part of a management system concerning quality
5


 Requirement is a need or expectation that is stated, generally implied, or obligatory
 Documented information the information contains on the media that required to be
controlled and maintained by an organization.
Table 2.1: Definition of quality

Definition

Strengths

Weaknesses

Quality is
excellence

Strong marketing and human
resource benefits
Universally recognizable - mark of
uncompromising standards and
high achievement

Provides little practical guidance to
practitioners
Measurement difficulties
Attributes of excellence may change
dramatically and rapidly
Sufficient number of customers must be
willing to pay for excellence

Quality is
value

Concept of value incorporates
multiple attributes
Focuses attention on a firm's
internal efficiency and external

effectiveness
Allows for comparisons across
disparate objects and experiences

Difficulty extracting individual components
of value judgment
Questionable inclusiveness
Quality and value are different constructs

Quality is
conformance
to
specifications

Facilitates precise measurement
Leads to increased efficiency
Necessary for global strategy
Should force disaggregation of
consumer needs
Most parsimonious and
appropriate definition for some
customers

Consumers do not know or care about
internal specifications
Inappropriate for services
Potentially reduces organizational
adaptability
Specifications may quickly become obsolete
in rapidly changing markets

Internally focused

Quality is
meeting
and/or
exceeding
expectations

Evaluates from customer's
perspective
Applicable across industries
Responsive to market changes
All-encompassing definition

Most complex definition
Difficult to measure
Customers may not know expectations
Idiosyncratic reactions
Pre-purchase attitudes affect subsequent
judgments
Short-term and long-term evaluations may
differ
Confusion between customer service and
customer satisfactions

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Figure 2.1: Amount of ISO 9001 certified companies
2.2 Lean & Six Sigma methodology

The History of Six Sigma started when Shewhart developed tools of statistical process control
and applied them at Motorola’s site. It is a long journey from that moment to the year 1988
when Motorola won the US Baldrige National Quality Award and made the Six Sigma concept
to be under the public’s attention. Similarly, Lean started when Henry Ford standardized work
and arranged conveyors to move products along the line which created the flow of production
at his car factory in 1913. The story of Lean & Six Sigma development was presented in Figure
2.2: Development history of Lean & Six Sigma [15]
From the success of Motorola, many organizations started using Six Sigma, and the most
famous one was General Electric under Jack Welch’s leadership, who popularized the Six Sigma
method. Six Sigma is a disciplined, data-driven methodology for eliminating defects in any
process. To achieve six sigma quality, a process must produce no more than 3.4 defects per
million opportunities. Six sigma principles are process improvement, statistical methods,
customer focus, attention to processes, and a management system focusing on high-return
improvement projects that result in continuous improvement and significant financial gains [14].

7


Figure 2.2: Development history of Lean & Six Sigma [15]
On the other hand, Ford’s technique with the production flow had moved world
manufacturing from centuries of craft production to mass production. Largely as a result, the
United States soon dominated the global economy [16]. After World War II, in Japan, Toyota
company tried to introduce Ford’s mass production system in their factory but suffered
resistance from employees. Then Toyota made a significant decision to work within its
organization to improve productivity. Eiji Toyoda and Taiichi Ohno, two engineers at Toyota
credited with the development of the so-called Toyota Production System based on what was
obtained from the West and the two pillars of Just-in-Time & autonomation. With many
initiatives on the ways of developing its system such as the Pull system, Kanban, Kaizen, and
SMED…, The Toyota Production System excelled and become the world’s benchmark for
manufacturing organizations all over the world with the name Lean manufacturing [17]. Lean

manufacturing is a manufacturing philosophy that focuses on delivering high-quality products
at the lowest price and at the right time. Lean manufacturing focuses on eliminating waste
or non-value-added activities. Lean basic principles on improving workflow, decreasing setup
8


time, eliminating waste, and conducting preventive maintenance are to speed up business
processes and return quick financial gains [14].
Lean and Six Sigma both aim to improve every aspect of the organization. Six Sigma
approach focused on identifying and eliminating anything that caused variation in the
process while Lean methodology is about creating flow and using tools to identify and
eliminate waste. When a company uses both Lean and Six Sigma, significant improvements
across the organization are achieved. In 1986, The George Group was the first to integrate and
popularize lean with Six Sigma. LSS can be described as a methodology that focuses on the
elimination of waste and variation, following the DMAIC structure, to achieve customer
satisfaction with regard to quality, delivery, and cost. It focuses on improving processes,
satisfying customers, and achieving better financial results for the business [18]. The integration
of Lean and Six Sigma is inevitable because Lean cannot bring a process under statistical
control, while Six Sigma alone cannot dramatically improve process speed or reduce invested
capital [19].
2.3 The integration between ISO 9001:2015 and Lean Sigma
Together with the popularity of ISO 9001:2015, Lean & Six Sigma has become well-known
within the SMEs community and in the academic environment. In Vietnam, we usually see
TQM applied in big corporates like Coca-Cola, Ford, and Toyota…while local SMEs implement
ISO 9001. Plenty of them also try to adopt Lean and Six Sigma to save costs for the organization
by eliminating waste and preventing non-quality. Researchers are working on the integration
between ISO 9001 Standard, Lean & Six Sigma as listed in the Summary of research on
integrating ISO 9001:2015 and LSS methodology.
Table 2.2: Summary of research on integrating ISO 9001:2015 and LSS methodology
Author(s)

Year

Chiarini

2011

Description
How the application of lean methodology affects and formalize
into ISO 9001 documents

9