1. QUALITY MANAGEMENT
ROOT CAUSE ANALYSIS
CA / PA BASIC TOOLS
Date: Oct 09, 2009
CA/PA BASIC TOOLS Rev 01 10.08.09
2. For most of us, it's a lot easier to jump
to solutions, isn't it?
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3. Objectives
Module 1:
Participants will learn how to:
• Create and use Pareto chart in the
analysis of a problem
• Implement steps for carrying out
effective RCA
• Select and apply tools that support
RCA
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4. Objectives
Module 2:
Participants will be able to:
• Define and explain the 8 – D as a
Problem Solving Method
• Apply the 8 Disciplines and
Concepts
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5. HOME PAGE
• INTRODUCTION
• MODULE 1
• MODULE 2
• APPLICATION
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6. INTRODUCTION
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7. Introduction
Introduction MODULE 1 MODULE 2
Definition of Terms
What it is
Why use it
RCA Process
How to use it
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8. Terms and Definition
Cause (causal factor) - a condition or event that results
in an effect
Direct Cause - cause that directly resulted in the
occurrence
Contributing Cause - a cause that contributed to the
occurrence, but by itself would not have caused the
occurrence
Root Cause - cause that, if corrected, would prevent
recurrence of a non-conformity and similar
occurrences
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9. RCA Definition
Root Cause Analysis - a process
designed for use in investigating and
categorizing the root causes of
events
A process of tracing a Problem to its Origins
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10. Root Cause Analysis Process
Step One:
Define the Problem
Step Two:
Collect Data
Step Three:
Identify Possible Causal Factors
Step Four:
Identify the Root Cause(s)
Step Five:
Recommend and Implement Solutions
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11. Module 1
Digging for the Root Causes
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12. Module 1 Table of Contents
MODULE 1 MODULE 2 APPLICATION
Histograms and Pareto Chart
Cause and Effect Diagram
What it is
How to use it
Examples
Summary
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13. Histograms- What it is
• A chart that graphically display the
distribution of a set of data.
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14. Pareto Chart - What it is
A Pareto chart allows data to be displayed as a bar chart
and enables the main contributors to a problem to be
highlighted.
It reveals that a
small number of
NCNs are
responsible for the
bulk of quality
issues,
a phenomenon
called the „Pareto
Principle‟.
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15. Pareto Chart – How to create it
1. Gather facts about the problem
2. Rank the contributions to the problem in order
of frequency.
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16. Pareto Chart – How to create it
(cont’n)
3. Draw the value as a bar chart.
4. add a line showing the cumulative
percentage of errors
5. Review the chart
6. Redefine classifications if necessary.
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17. Pareto Analysis Example
• Chart 1 : The chart gives summary information and starts the cumulative % count at
the top of the first bar:
Pareto of D3 Small Engine Card Faults
600 100
500 80
400
Percent
60
Count
300
40
200
20
100 .
pec lan
e
pai
r
.S atp d Boa
rd
Re v al
ec t
d He
r ed tec mo
lty tFitlte
E
t ge fotue h
i tg
ni tmid r y Re r
0 d Fau ee
mp
. non
iShild is
Mhr Ecsos fo na ble
m
t ne
c to 0
ge t Mg
noton Joc
T ou nt t Mi horn tion
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tMis s pt n t
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iee
ra Pr o Co ina
tD o g
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Cmtn orn
fCm
ms
t mp gs iBeg
yo
WL
Pr e kol rty
lde l
S am er s
mp om Wr
mp eJo i Co Le nk
n hio So au ont
C C C D L
Lo T F C Oth
Defect
Count 141 139 69 52 22 20 20 17 17 17 16 13 10 10 10 8 6 5 29
Percent 23 22 11 8 4 3 3 3 3 3 3 2 2 2 2 1 1 1 5
Cum % 23 45 56 65 68 71 75 77 80 83 85 87 89 91 92 94 95 95 100
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18. Pareto Analysis Example
• Example 2 : a series of Pareto charts drill down to more detail:
Fault by Main Cause
100
70 1st level Analysis
gives “Design”
60 80
50
Percent
60
Count
40 as main cause of
30 40
20 failure
20
10
0
ign pon
ent
er
0
2nd level Analysis gives
Des Com d
breakdown of “Design”
Buil Oth
Defect
Count 57 13 4 2
Percent 75.0 17.1 5.3 2.6
Cum % 75.0 92.1 97.4 100.0
Design Faults
100
50
80
40
Percent
60
Count
30
40
20
10 20
le
0 dule rs odu on 0
rM r ati
t Mo Moto rt uc e alib
nec que Sta r ans d IC C n
Con Tor Cold T AS IOP Imo
Defect
Count 21 10 8 8 5 3 2
Percent 36.8 17.5 14.0 14.0 8.8 5.3 3.5
Cum % 36.8 54.4 68.4 82.5 91.2 96.5 100.0
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19. Pareto Analysis Example
• Example 3 : if the original Pareto is very flat, be prepared to cut the defects in a
different way, here, it is 40:60
Pareto Chart for Child11
100
200
80
Percent
60
Count
100 40
20
0 - 10 7E 0
4- 4
116 823 727
788 646 777 780 782 795 564- 8 6- 7 - 564-
66 40
CC CC CC CC CC CC 40- 40- er s
KD KD KD KD KD KD Oth
Defect
Count 18 13 11 11 11 10 9 9 8 138
Percent 7.6 5.5 4.6 4.6 4.6 4.2 3.8 3.8 3.4 58.0
Cum % 7.6 13.0 17.6 22.3 26.9 31.1 34.9 38.7 42.0 100.0
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20. Pareto Analysis Example
How it helps
Pareto Analysis is a useful tool to:
• identify and prioritize major problem areas based on frequency of
occurrence;
• separate the „vital few‟ from the „useful many‟ things to do;
• identify major causes and effects.
The technique is often used in conjunction with Brainstorming and Cause and
Effect Analysis.
HINT !
The most frequent is not
always the most important! Be
aware of the impact of other
causes on Customers or goals.
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21. Pareto Chart and Analysis
A method for showing the distribution of Process Steps
quantitative data and identifying those Pareto
with the greatest impact.
Identify the problem and the potential
Summary
direct or contributing causes
Pareto Charts provide a visual representation of
the variables which contribute to problems or Collect data about each of the potential
direct or contributing causes
issues.
Pareto Charts can be used as a prioritization tool
to aid in focusing on the top issues which
Construct the Pareto Chart:
Causes on Horizontal Axis
contribute to specific conditions.
Frequency of events on Vertical Axis
Pareto analysis is an approach which ranks the
contributing factors and identifies which are the Identify the Vital Few (those with the
highest number of occurrences)
ones which have the most impact on a problem or
issue. Often referred to as an approach for
“separating the vital few from the trivial Develop Corrective Action or
many”, sometimes referred to as the “80-20 rule” Improvement Action Plans for those
identified as the Vital Few
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22. CAUSE AND EFFECT
Ishikawa/Fish Bone Diagram
Procedures People
Problem
Equipment Materials
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23. Cause and Effect
• Cause and Effect Analysis is a tool for
identifying all the possible causes associated
with a particular problem
Valuable for:
• Focusing on causes not symptoms
• Providing a picture of why an effect is happening
• Establishing a sound basis for further data gathering
and action
• Identifying all of the areas that need to be tackled
to generate a positive effect
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24. Cause and Effect Sources of Variation
Sources of Variation is categorized as
follows
1. People
2. Method
3. Machine
4. Material
5. Environment
6. Measuring System
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25. How to do it
• 1. Identify the Problem/Issue
• 2. Brainstorm
3. Draw fishbone diagram
Place the effect at the head of the “fish”
Include the 6 recommended categories shown below
People Method Machine
Problem or
Issue
Material Environment Measurement System
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26. How to do it (cont’n)
• 4. Align Outputs with Cause Categories
• 5. Allocate Causes
• 6. Analyze for Root Causes
• 7. Test for Reality
Tip !
The 6 categories recommended will address almost all scenarios. However, there is no
one perfect set of categories. You may need to adapt to suit the issue being analyzed.
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27. Sources of Variation - People
People
• The activities of the workers.
• Variations caused by
skill, knowledge, competency and
attitude
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28. Sources of Variation - Method
Method
• The methods used to produce the
products.
• Variations caused by inappropriate
methods or processes.
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29. Sources of Variation - Machine
Machine
• The equipment used to produce the
products.
• Variations caused by
temperature, tool wear and
vibration.
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30. Sources of Variation - Material
Material
• The "ingredients" of a process.
• Variations caused by materials that
differ by industry, product
and stage of production.
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31. Sources of Variation - Environment
Environment
• The methods used to control the
environment.
• Variations caused by temperature
changes, humidity etc.
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32. Sources of Variation – Measurement System
Measurement System
• The methods and instruments used to
evaluate products.
• Variations caused by measuring
techniques, or calibration and
maintenance of the instruments.
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33. Cause and Effect Analysis Example
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34. PROBLEM SOLVING FAILURE
• Jumping to conclusion
• Failure to define problem
• Failure to find the root cause
• Weak problem solving
• No execution of corrective action
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35. PROBLEM SOLVING SUCCESS
- Problem is clearly defined.
- Problem is accepted
- As an opportunity/challenge to improve
- True root cause is found
- Implemented an effective and
irreversible corrective and preventive
action
- Problem did not re-occur
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36. Cause and Effect Diagram (Ishikawa)
A visual brainstorming tool used to help identify and categorize potential root causes named
for Kaoru Ishikawa.
Ishikawa Fishbone Template
Summary
The development of the cause and effect
Fishbone diagram is credited to Kaoru
Ishikawa, who pioneered quality management
processes in the Kawasaki shipyards. Measurement
Measurement Methods
Methods Machinery
Machinery
The cause and effect diagram is used to
explore potential causes (or inputs) that
result in a single undesirable effect (UDE, or
output). Causes are categorized under six UDE
headings, namely Machinery, Methods, Causes, inputs,
or sources
Measurement, Manpower, Materials, and of variation
Environment. Potential causes can be
arranged according to their level of
importance or detail, resulting in a depiction
of relationships and hierarchy of events. It is Manpower
Manpower Materials
Materials Environment
Environment
the hierarchy that creates a map that looks
somewhat like fish bones, hence the name.
The Ishikawa Fishbone Diagram is intended
help you brainstorm and search for potential
root causes or identify areas where there may A UDE is an UnDesireable Effect
be problems by questioning the existence of
causes under each of the six categories.
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37. Action Reflection
Wait! I think I missed
$$$
something
It isn’t that they
cannot see the
solution,
It’s that they can’t see
the problem.
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38. Created by:
Sid Calayag – Lead Auditor
Quality Management System
Presented by: Sid Calayag
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Notes de l'éditeur
The presentation is organized in such a way that we can move from one part (module) of the presentation to another. Also included are two ice breakers during or after the scheduled coffee break. Application form each module is also included although in such a way that it can be part of each or both module, although the advance application will require module 2 to better understand its application.
Root Cause Analysis - structured and thorough review of problem designed to identify and verify what is causing the symptomsa process for understanding and solving a problem. Useful process for understanding and solving a problem. Root Cause AnalysisTracing a Problem to Its OriginsIn medicine, it's easy to understand the difference between treating symptoms and curing a medical condition. Sure, when you're in pain because you've broken your wrist, you WANT to have your symptoms treated – now! However, taking painkillers won't heal your wrist, and true healing is needed before the symptoms can disappear for good.But when you have a problem at work, how do you approach it? Do you jump in and start treating the symptoms? Or do you stop to consider whether there's actually a deeper problem that needs your attention?If you only fix the symptoms – what you see on the surface – the problem will almost certainly happen again. which will lead you to fix it, again, and again, and again. If, instead, you look deeper to figure out why the problem is occurring, you can fix the underlying systems and processes that cause the problem. Root Cause Analysis (RCA) is a popular and often-used technique that helps people answer the question of why the problem occurred in the first place. Root Cause Analysis seeks to identify the origin of a problem. It uses a specific set of steps, with associated tools, to find the primary cause of the problem, so that you can:Determine what happened.Determine why it happened.Figure out what to do to reduce the likelihood that it will happen again. RCA assumes that systems and events are interrelated. An action in one area triggers an action in another, and another, and so on. By tracing back these actions, you can discover where the problem started and how it grew into the symptom you're now facing.You'll usually find three basic types of causes:Physical causes - Tangible, material items failed in some way (for example, a car's brakes stopped working). Human causes - People did something wrong. or did not doing something that was needed. Human causes typically lead to physical causes (for example, no one filled the brake fluid, which led to the brakes failing).Organizational causes - A system, process, or policy that people use to make decisions or do their work is faulty (for example, no one person was responsible for vehicle maintenance, and everyone assumed someone else had filled the brake fluid). Root Cause Analysis looks at all three types of causes. It involves investigating the patterns of negative effects, finding hidden flaws in the system, and discovering specific actions that contributed to the problem. This often means that RCA reveals more than one root cause.You can apply Root Cause Analysis to almost any situation. Determining how far to go in your investigation requires good judgment and common sense. Theoretically, you could continue to trace root causes back to the Stone Age, but the effort would serve no useful purpose. Be careful to understand when you've found a significant cause that can, in fact, be changed.
The Root Cause Analysis ProcessRoot Cause Analysis has five identifiable steps.Step One: Define the ProblemWhat do you see happening? What are the specific symptoms? Step Two: Collect DataWhat proof do you have that the problem exists?How long has the problem existed?What is the impact of the problem? You need to analyze a situation fully before you can move on to look at factors that contributed to the problem. To maximize the effectiveness of your Root Cause Analysis, get together everyone – experts and front line staff – who understands the situation. People who are most familiar with the problem can help lead you to a better understanding of the issues.A helpful tool at this stage is CATWOE. With this process, you look at the same situation from different perspectives: the Customers, the people (Actors) who implement the solutions, the Transformation process that's affected, the World view, the process Owner, and Environmental constraints. Step Three: Identify Possible Causal FactorsWhat sequence of events leads to the problem? What conditions allow the problem to occur?What other problems surround the occurrence of the central problem? During this stage, identify as many causal factors as possible. Too often, people identify one or two factors and then stop, but that's not sufficient. With RCA, you don't want to simply treat the most obvious causes - you want to dig deeper.Use these tools to help identify causal factors:Appreciation - Use the facts and ask "So what?" to determine all the possible consequences of a fact.5 Whys - Ask "Why?" until you get to the root of the problem. Drill Down - Break down a problem into small, detailed parts to better understand the big picture. Cause and Effect Diagrams - Create a chart of all of the possible causal factors, to see where the trouble may have begun. Step Four: Identify the Root Cause(s)Why does the causal factor exist?What is the real reason the problem occurred? Use the same tools you used to identify the causal factors (in Step Three) to look at the roots of each factor. These tools are designed to encourage you to dig deeper at each level of cause and effect. Step Five: Recommend and Implement SolutionsWhat can you do to prevent the problem from happening again?How will the solution be implemented?Who will be responsible for it?What are the risks of implementing the solution? Analyze your cause-and-effect process, and identify the changes needed for various systems. It's also important that you plan ahead to predict the effects of your solution. This way, you can spot potential failures before they happen.One way of doing this is to use Failure Mode and Effects Analysis (FMEA). This tool builds on the idea of risk analysis to identify points where a solution could fail. FMEA is also a great system to implement across your organization; the more systems and processes that use FMEA at the start, the less likely you are to have problems that need Root Cause Analysis in the future.Impact Analysis is another useful tool here. This helps you explore possible positive and negative consequences of a change on different parts of a system or organization.Another great strategy to adopt is Kaizen, or continuous improvement. This is the idea that continual small changes create better systems overall. Kaizen also emphasizes that the people closest to a process should identify places for improvement. Again, with kaizen alive and well in your company, the root causes of problems can be identified and resolved quickly and effectively. Key PointsRoot Cause Analysis is a useful process for understanding and solving a problem. Figure out what negative events are occurring. Then, look at the complex systems around those problems, and identify key points of failure. Finally, determine solutions to address those key points, or root causes. You can use many tools to support your Root Cause Analysis process. Cause and Effect Diagrams and 5 Whys are integral to the process itself, while FMEA and Kaizen help minimize the need for Root Cause Analysis in the future. As an analytical tool, Root Cause Analysis is an essential way to perform a comprehensive, system-wide review of significant problems as well as the events and factors leading to them.Why Do Root Cause Analysis?“Just fix it, there is too much to do.”“We don’t have time to think, we need results now.”Reality - fix symptoms without regard to actual causesRoot Cause Analysis - structured and thorough review of problem designed to identify and verify what is causing the symptoms
Pareto Analysis is used to record and analyse data relating to a problem in such a way as to highlight the most significant areas, inputs or issues. Pareto Analysis often reveals that a small number of failures are responsible for the bulk of quality costs, a phenomenon called the ‘Pareto Principle.’This pattern is also called the ‘80/20 rule’ and shows itself in many ways. For example: 80% of sales are generated by 20% of customers. 80% of Quality costs are caused by 20% of the problems. 20% of stock lines will account for 80% of the value of the stock.A Pareto diagram allows data to be displayed as a bar chart and enables the main contributors to a problem to be highlighted.As a basic Quality Improvement tool, Pareto Analysis can: define categories of defects which cause a particular output (product, service, unit) to be defective; count the frequency of occurrence of each defect; display graphically as a bar chart, sorted in descending order, by frequency of defect; use a second y axis to show the cumulative % of defects .Vilfredo Pareto was an economist who is credited with establishing what is now widely known as the Pareto Principle or 80/20 rule. When he discovered the principle, it established that 80% of the land in Italy was owned by 20% of the population. Later, he discovered that the pareto principle was valid in other parts of his life, such as gardening: 80% of his garden peas were produced by 20% of the peapods.Some Sample 80/20 Rule Applications· 80% of process defects arise from 20% of the process issues.· 20% of your sales force produces 80% of your company revenues.· 80% of delays in schedule arise from 20% of the possible causes of the delays.· 80% of customer complaints arise from 20% of your products or services.(The above examples are rough estimates.)
1. Gather facts about the problem, using Check Sheets or Brainstorming, depending on the availability of information.2. Rank the contributions to the problem in order of frequency.3. Draw the value (errors, facts, etc) as a bar chart.4. It can also be helpful to add a line showing the cumulative percentage of errors as each category is added. This helps to identify the categories contributing to 80% of the problem. 5. Review the chart – if an 80/20 combination is not obvious, you may need to redefine your classifications and go back to Stage 1 or 2. Examples When possible, use Minitab’s version, as an industry standard, rather than creating one in Excel - refer to Example 1 in this section Use a series of Pareto charts to drill down to more detail - Example 2 Recognise the 80: 20 principle but if the original Pareto is very flat be prepared to cut the defects in a different way, say 40:60 - Example 3 Minitab gives an extra dimension to Pareto Analysis - Example 4
1. Gather facts about the problem, using Check Sheets or Brainstorming, depending on the availability of information.2. Rank the contributions to the problem in order of frequency.3. Draw the value (errors, facts, etc) as a bar chart.4. It can also be helpful to add a line showing the cumulative percentage of errors as each category is added. This helps to identify the categories contributing to 80% of the problem. 5. Review the chart – if an 80/20 combination is not obvious, you may need to redefine your classifications and go back to Stage 1 or 2. Examples When possible, use Minitab’s version, as an industry standard, rather than creating one in Excel - refer to Example 1 in this section Use a series of Pareto charts to drill down to more detail - Example 2 Recognise the 80: 20 principle but if the original Pareto is very flat be prepared to cut the defects in a different way, say 40:60 - Example 3 Minitab gives an extra dimension to Pareto Analysis - Example 4
Construct the Pareto chart – Example 1Use a series of Pareto charts to drill down to more detail – Example 2 Recognise the 80: 20 principle but if the original Pareto is very flat be prepared to cut the defects in a different way, say 40:60 - Example 3 Create more Pareto by cutting across another variables- Example 4
At first glance, this looks unhelpful. But of 238 data points, most were counts of 1 or 2. A full Pareto would be very flat.Therefore after the first cumulative 42% of defects (100) , the balance of defects (138) are blocked together as “others”.This enables us to see that a “top 9” of defects can be analysed - most are “S-clip” problems (links between ICs and PCB
Examples of Unacceptable Root Cause- Operator Error- It was broken (equipment, gauge, tooling)The process didn’t do what it was supposed to doDidn’t know what to doIt only happened onceFrequent use of “not able to determine/unresolved”
valuable tool for: Focusing on causes not symptoms capturing the collective knowledge and experience of a group Providing a picture of why an effect is happening Establishing a sound basis for further data gathering and action Cause and Effect Analysis can also be used to identify all of the areas that need to be tackled to generate a positive effect.
1. Identify the Problem/IssueSelect a particular problem, issue or effect. Make sure the problem is specific, tightly defined and relatively small in scope and that everyone participating understands exactly what is being analyzed. Write the problem definition at the top of the flip chart or whiteboard.2. Brainstorm Conduct a Brainstorm of all the possible causes of the effect, i.e., problem.Have a mixed team from different parts of the process (e.g., assemblers and testers).Get a “fresh pair of eyes” - from someone who is not too close to the process.Have a facilitator - an impartial referee.Everyone is an equal contributor (“leave stripes at the door”).Fast and furious - go for quantity rather than quality (of ideas) at first.Involve everyone, or question why he/she is here.Timing - set an upper limit and best time/day of the week.Offer an incentive (free lunch?).Know when to stop.Recognize that this is a snapshot of how the group thinks today.Re-visit the problem again.Refer also to the Process Mapping tool.Consider (how) should you involve your customer?Write each idea on a Post-It® to make it easy to transfer them onto the fishbone diagram later. Be careful not to muddle causes and solutions at this stage. It is important to brainstorm before identifying cause categories otherwise you can constrain the range of ideas. However, if ideas are slow in coming use questions such as, ‘what about?’, to prompt thoughts.3. Draw fishbone diagram Place the effect at the head of the “fish” Include the 6 recommended categories shown below
4. Align Outputs with Cause CategoriesReview your brainstorm outputs and align with the recommended major cause categories, e.g., the People, Method, Machine, Material, Environment and Measurement System. Note:These may not fit every situation and different major categories might well be appropriate in some instances, however, the total should not exceed six. Other categories may include Communications, Policies, Customer/Supplier Issues etc.5. Allocate CausesTransfer the potential causes from the brainstorm to the diagram, placing each cause under the appropriate category.If causes seem to fit more than one category then it is acceptable to duplicate them. However, if this happens repeatedly it may be a clue that the categories are wrong and you should go back to step 4.Related causes are plotted as ‘twigs’ on the branches. Branches and twigs can be further developed by asking questions such as ‘what?’, ‘why?’ ‘how?’, ‘where?’ This avoids using broad statements that may in themselves be effects. Beware, however, of digging in and getting into bigger issues that are completely beyond the influence of the team.6. Analyze for Root CausesConsider which are the most likely root causes of the effect. This can be done in several ways:Through open discussion among participants, sharing views and experiences. This can be speeded up by using Consensus Decision Making.By looking for repeated causes or number of causes related to a particular category.By data gathering using Check Sheets, Process Maps, or customer surveys to test relative strengths through Pareto Analysis.Once a relatively small number of main causes have been agreed upon, Paired Comparisons, can be used to narrow down further.Some groups find it helpful to consider only those causes they can influence.7. Test for RealityTest the most likely causes by, e.g., data gathering and observation if this has not already been done.The diagram can be posted on a wall and added to / modified as further ideas are generated either by the team or by others who can review the teams' work.Cause and Effect Analysis can be combined with Process Mapping.A fishbone may be developed for each discrete activity within the process that is generating the output / effect so that causes are linked to particular steps in the process
Types of Questions that may be Asked Does the person have adequate supervision and support? Does the person know what he is expected to do in his job? How much experience does the person have? Does the person have the proper motivation to do his best work? Is the person satisfied or dissatisfied with his job?Is the person more- or less-productive at certain times of the day? Do physical conditions such as light or temperature affect their work? Does the person have the tools/equipment needed to do the job? Who does the person contact when problems arise? Is the work load reasonable?
Types of Questions that may be Asked How is the method used defined? Is the method regularly reviewed for adequacy? Is the method used affected by external factors? Have other methods been considered? How does the operator know if the method is operating effectively?Is statistical analysis used to verify the effectiveness of the method? What adjustments must the operator make during the process? Have any changes been made recently in the process?
Types of Questions that may be Asked How old is the equipment or machinery? Is it maintained regularly? Is the machine affected by heat or vibration or other physical factors? How does the operator know if the machine is operating correctly?Is statistical analysis used to verify the capability of the machine? What adjustments must the operator make during the process? Have any changes been made recently in the process?
Types of Questions that may be Asked How is the material produced? How is the material verified? How old is the material? How is quality judged prior to your operation? What is the level of quality?How is the material packaged? Can temperature, light or humidity affect the material quality? Who is the material supplier? Has there been a change in suppliers?
Types of Questions that may be Asked How are conditions monitored? How are conditions controlled? How is the control measuring equipment calibrated? Are there changes in conditions at different times of the day? How does change impact the processes being used? How does change impact the materials being used?
Types of Questions that may be Asked How frequently are products inspected? How is the measuring equipment calibrated? Are all products measured using the same tools or equipment? How are inspection results recorded? Do inspectors follow the same procedures? Do inspectors know how to use the test equipment?
A Cause and Effect diagram (also known as a Fishbone or Ishikawa diagram) graphically illustrates the results of the analysis and is constructed in steps. Cause and Effect Analysis is usually carried out by a group who all have experience and knowledge of the cause to be analyzed. Cause-and-Effect diagrams graphically display potential causes of a problem The layout shows Cause-and-Effect relationships between the potential causesAllow team members to specify where ideas fit into the diagramClarify the meaning of each idea using the group to refine the ideas. For example:Is also Called, “Fishbone" or "Ishikawa" diagram is named after its creator, Kaoru Ishikawa.Is used to systematically list all the different potential causes for a specific problem (or effect). Is often used to help identify the reasons why a process goes wrong.A Cause and Effect diagram graphically illustrates the results of the analysis and is constructed in steps. Cause and Effect Analysis is usually carried out by a group who all have experience and knowledge of the cause to be analyzed. Cause-and-Effect diagrams graphically display potential causes of a problem The layout shows Cause-and-Effect relationships between the potential causesThe Cause and Effect diagram is one of several charts used during Brainstorming to organizing ideas into common themes. This format helps with the process of distinguishing between alternatives, identifying common threads, and keeping the ideas flowing. This method also allows the team to easily divide up the ideas for further work.Organize the topic, team and write down the general categories on the chart. Brainstorm the ideas about the potential causes using good brainstorming practices (no bad ideas, everyone gets a voice). Illustrates how several potential causes may lead to the same effect. Generally takes on the shape of a fishbone. Potential causes are organized under common headings such as Materials, Machinery, Methods, Environment, Process & Measurement It is common for people working on improvement efforts to jump to conclusions without studying the causes, target one possible cause while ignoring others, and take actions aimed at surface symptomsCause-and-effect diagrams are designed to:Stimulating thinking during a brainstorm of potential causesProviding a structure to understand the relationships between many possible causes of a problemGiving people a framework for planning what data to collectServing as a visual display of causes that have been studiedHelping team members communicate within the team and with the rest of the organization
PROBLEM SOLVING FAILURE- JUMPING TO CONCLUSIONS,NO FACT FINDING- SHOTGUN ROOT CAUSE - FAILURE TO DEFINE THE PROBLEM- FAILURE TO FIND THE ROOT CAUSEWEAK PROBLEM SOLVING SKILL-NO EXECUTION OF CORRECTIVE ACTIONSACTION IS ONLY FOR THE SHOW NO COMMITMENT/OWNERSHIPTIME FACTOR- COST CONSTRAINTS
PROBLEM SOLVING SUCCESSProblem is clearly defined.Problem is acceptedAs an opportunity/challenge to improve- True root cause is found- Implemented an effective and irreversible corrective and preventive action- Problem did not re-occur
PROBLEM SOLVING SUCCESSProblem is clearly defined.Problem is acceptedAs an opportunity/challenge to improve- True root cause is found- Implemented an effective and irreversible corrective and preventive action- Problem did not re-occur
