Slides of Quality assurance

1. Quality Assurance

2. What is quality?
• Quality is the degree to which a commodity meets the requirements
of the customer at the start of its life
• ISO 9000:2015 : “Degree to which a set of inherent characteristics of
an object fulfill requirements.”
• The totality of features and characteristics of a product or
service that bears on its ability to satisfy stated or implied
needs. – American Society for Quality

3. ► User-based: better performance, more
features
► Manufacturing-based: conformance to
standards, making it right the first time
► Product-based: specific and measurable
attributes of the product
Different Views of Quality

4. 6-4
Performance or operation.
Features
Reliability.
Durability.
Conformance.
Serviceability.
Aesthetics.
Perceived quality.
Quality
Dimensions of Quality for Goods

5. Implications of Quality
1. Company reputation
► Perception of new products
► Employment practices
► Supplier relations
2. Product liability
► Reduce risk
3. Global implications
► Improved ability to compete

6. Costs of Quality
“Quality does not Cost, it pays”

7. Prevention costs
• Reducing the potential for defects
• Do the things right first time is a widely accepted slogan.
• E.g. Quality planning, Inspection or test planning, design and
development of inspection and test equipment, quality system
audit.
Appraisal costs
• Appraisal determines conformance of a product or service.
• Evaluating products, parts, and services incurs cost.
• E.g. cost of incoming inspection, cost of in process inspection,
cost of final inspection, cost of evaluation of stocks, etc.

8. Internal failure costs
• Cost of producing defective parts or service before
delivery.
• Associated to correcting reworking and disposing.
• E.g. scrap, rework, trouble shooting, analysis of defect
and failure, loss of material due to defective material.
External failure costs
• Cost due to defects discovered after delivery
• Eg. Management complaints, product or customer
service, product liability, product returns, product
recalls and product replacement, marketing errors.

9. Costs of Quality

10. What are standards?
•A standard is a document that provides
requirements, specifications, guidelines or
characteristics that can be used consistently to
ensure that materials, products, processes and
service are fit for their purpose.
•They give world class specifications for
products, service and systems, to ensure
quality, safety and efficiency.

12. ISO
It is an international body which develops different types of
standards.
Established in 1947.
Its technical committees and sub-committees play important role
in developing standards.
There are 161 member countries of ISO till now.
ISO has published more than 19000 international standards and
related documents, covering almost every industry, from
technology, to food safety, to agriculture and healthcare

13. ISO 9000
It is a series of standards that outlines the requirements
for quality management system (QMS).
ISO 9000 series consists five types of standards
• ISO 9000: It relates to quality assurance. It is a set of guidelines for
selection and use of standards, ISO 9001, 9002, 9003.
• ISO 9001: It is for companies which are involved in Design,
Development, Production, Installation and servicing of products or
services.
• ISO 9002: It is for the companies which are involved in Production,
Installation and servicing of products or services.

14. • ISO international standards are applicable through out
the earth.
• ISO 9000 certificate is not valid for more than 3 years.
• Re-audits are done by ISO registrars every three years.
• Surveillance audits are conducted at least twice a year.

15. The ISO 9000-2015 Seven Quality Management Principles
or Principles of TQM
Customer focus: The primary focus of quality management
is to meet customer requirements and to strive to exceed
customer expectations.
Leadership: Leaders at all levels establish unity of purpose
and direction and create conditions in which people are
engaged in achieving the organization’s quality objectives.
Engagement of people: Competent, empowered and
engaged people at all levels throughout the organization are
essential to enhance the organization’s capability to create
and deliver value.

16. Process Approach: Consistent and predictable results are
achieved more effectively and efficiently when activities are
understood and managed as interrelated processes that function
as a coherent system.
Improvement: Successful organizations have an ongoing
focus on improvement.
Evidence Based Decision Making: Decisions based on the analysis
and evaluation of data and information are more likely to
produce desired results.
Relationship Management: For sustained success, organizations
manage their relationships with interested parties, such as
providers.

17. TQM
Originally quality was achieved by inspection – screening out defects
before they were noticed by customers.
The quality control (QC) concept developed a more systematic
approach to not only detecting, but also treating quality problems. It
focuses on product.
Quality assurance (QA) widened the responsibility for quality to
include functions other than direct operations. It also made increasing
use of more sophisticated statistical quality techniques. It focuses on
process.
TQM included much of what went before but developed its own
distinctive themes. We will use some of these themes to describe how
TQM represents a clear shift from traditional approaches to quality.

18. Total Quality Management (TQM)
It is a management philosophy of continuous improvement
Encompasses entire organization from supplier to customer.
Commitment by management to a continuing company-wide
drive toward excellence in all aspects of products and
services that are important to the customer.

19. Involves three key philosophies
•Continuous improvement
•Involvement of everyone
•Customer satisfaction

20. TQM Model As Per ISO 9000

21. TQM Tools
► Tools for Generating Ideas
► Check Sheet
► Scatter Diagram
► Cause-and-Effect Diagram
► Tools to Organize the Data
► Pareto Chart
► Flowchart (Process Diagram)
For more insights refer the Ajay B. Sthapit Book

22. TQM Tools
► Tools for Identifying Problems
► Histogram
► Statistical Process Control Chart

23. Hour
Defect 1 2 3 4 5 6 7 8
A
B
C
Seven Tools of TQM
(a) Check Sheet: An organized
method of recording data
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24. Seven Tools of TQM
(b) Scatter Diagram: A graph of the
value of one variable vs. another
variable
Absenteeism
Productivity

25. Seven Tools of TQM
(c) Cause-and-Effect Diagram/ Fish
Bone Diagram/ Ishikawa Diagram: A
tool that identifies process elements
(causes) that might effect an outcome
Cause
Materials Methods
Manpower Machinery
Effect

26. Cause-and-Effect Diagrams
Material
(ball)
Method
(shooting process)
Machine
(hoop &
backboard)
Manpower
(shooter)
Missed
free-throws
Rim alignment
Rim size
Backboard
stability
Rim height
Follow-through
Hand position
Aiming point
Bend knees
Balance
Size of ball
Lopsidedness
Grain/Feel
(grip)
Air pressure
Training
Conditioning Motivation
Concentration
Consistency

27. Seven Tools of TQM
(d) Pareto Chart: A graph to identify and plot problems or
defects in descending order of frequency
80% of activity is caused by 20% of factors. Focus on those
20% factors.
Frequency
Percent
A B C D E

28. Pareto Charts
Number of
occurrences
Room svc Check-in Pool hours Minibar Misc.
72% 16% 5% 4% 3%
12
4 3 2
54
– 100
– 93
– 88
– 72
70 –
60 –
50 –
40 –
30 –
20 –
10 –
0 –
Frequency(number)
Causes and percent of the total
Cumulativepercent
Data for October

29. Seven Tools of TQM
(e) Flowchart (Process Diagram): A chart
that describes the steps in a process

30. Flow Charts
MRI Flowchart
1. Physician schedules MRI
2. Patient taken to MRI
3. Patient signs in
4. Patient is prepped
5. Technician carries out MRI
6. Technician inspects film
7. If unsatisfactory, repeat
8. Patient taken back to room
9. MRI read by radiologist
10. MRI report transferred to
physician
11. Patient and physician
discuss
11
10
20%
9
8
80%
1 2 3 4 5 6 7

31. Seven Tools of TQM
(f) Histogram: A distribution showing the
frequency of occurrences of a variable
Distribution
Repair time (minutes)
Frequency

32. Seven Tools of TQM
(g) Statistical Process Control Chart: A chart
with time on the horizontal axis to plot
values of a statistic
Upper control limit
Target value
Lower control limit
Time

33. Statistical Quality Control (SQC)
It uses the statistical tools like sampling and control charts for
quality control.
The basis of SQC is degree of variability.
Provides a statistical signal when assignable causes are
present.
Detect and eliminate assignable causes of variation.

34. Causes of Variation
Variation arises due to two causes.
• A. Chance Causes
• Also called chance variation or natural variation or allowable
variation.
• Beyond the human control.
• B. Assignable Causes
• Also called special causes of variation
• Those causes which can be identified and controlled.
• Pose severe impact on the process

35. Difference Between Chance causes and Assignable Causes
Chance Causes Assignable Causes
Consists many individual causes Consists one or just a few
individual causes
Results in small amount of
variation
Results in large amount of
variation
Elimination of chance causes is not
feasible
Elimination is feasible and should
be done.
E.g. voltage fluctuation and
variations in temperatures.
E.g. Negligence of operators,
defective raw materials, faulty
equipments.

36. Objectives of SQC
Maintaining quality
Optimum use of raw materials
Identifying the process failures
Taking necessary steps to maintain quality
To improve the quality of the products
To use the statistical tools of quality control

37. Types of SQC
• SQC
1. Product Control (Acceptance Sampling)
A. For Variables
B. For Attributes
Types of statistical tools for both- variables and attributes
• Single sampling plan
• Double sampling plan
• Sequential sampling plan
• Process Control
A. For Variables
• X bar chart
• R-chart
B. For Attributes
• P-chart
• np-chart
• C-chart

38. 1. Acceptance Sampling
 Form of quality testing used for incoming
materials or finished goods
 Take samples at random from a lot
(shipment) of items
 Inspect each of the items in the sample
 Decide whether to reject the whole lot
based on the inspection results
 Only screens lots; does not drive quality
improvement efforts

39. Acceptable Quality Level (AQL)
• Associated to lowest total cost of quality
• Set by judgement
• Expressed in percentage of allowable defects
• E.g. 1% defective ball-pen refills are acceptable .

40. Single Sampling Plan
• Only one sample is taken from the lot and is inspected.
• Decision to accept or reject the lot depends on the samples.
Double Sampling Plan
• Two different samples of varying size are taken for inspecting.
• If both sample does not give same results, the third sample is taken.
Sequential Sampling
• Sample size is taken and no. of Defects are also identified.
• No. of defection is checked for accepting or rejecting the lot.

41. 2. Process Control
It is more pro-active measure than product control.
Controlling the quality of goods with respect to
certain standard maintained by the business
organization in the process of production.
Makes use of control chart.

42. Control Chart
Developed by Walter A. Schewart in 1924.
It is a graphic method of identifying if the process is in control or not.
It consists three lines
• Central Limit (Central Line or CL): represents the desired standard
• Upper Control Limit (UCL): represents highest number/proportion of defects etc.
• Lower Control Limit (LCL): represents lowest number/proportion of defects, etc.
Types: X-bar Chart, R-Chart, P-chart, np-chart and C-chart

43. UCL
CL
LCL

44. Methods of Minimizing Non-sampling Errors
• Checking the sampling process
• Preparation of questionnaire
• Pilot survey
• Fix procedures
• Use of competent manpower
• Provide information
• Provide training
• Use of experts
• Checking data processing and analysis