1. 1Determining Root Cause 1
Determining the Root
Cause of a Problem
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2. 2Determining Root Cause 2
Why Determine Root Cause?
• Prevent problems from recurring
• Reduce possible injury to personnel
• Reduce rework and scrap
• Increase competitiveness
• Promote happy customers and stockholders
• Ultimately, reduce cost and save money
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3. 3Determining Root Cause 3
Look Beyond the Obvious
• Invariably, the root cause of a
problem is not the initial reaction
or response.
• It is not just restating the Finding
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4. 4Determining Root Cause 4
Often the Stated Root Cause
is the Quick, but Incorrect Answer
For example, a normal response is:
•Equipment Failure
•Human Error
Initial response is usually the symptom, not
the root cause of the problem. This is why
Root Cause Analysis is a very useful and
productive tool.
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5. 5Determining Root Cause 5
Most Times Root Cause
Turns Out to be Much More
Such as:
• Process or program failure
• System or organization failure
• Poorly written work instructions
• Lack of training
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6. 6Determining Root Cause 6
What is Root Cause Analysis?
Root Cause Analysis is an in-depth
process or technique for identifying the
most basic factor(s) underlying a
variation in performance (problem).
• Focus is on systems and processes
• Focus is not on individuals
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7. 7Determining Root Cause 7
When Should Root Cause
Analysis be Performed?
• Significant or consequential events
• Repetitive human errors are occurring
during a specific process
• Repetitive equipment failures associated
with a specific process
• Performance is generally below desired
standard
• May be SCAR or CPAR (NGNN) driven
• Repetitive VIRs
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8. 8Determining Root Cause 8
How to Determine the Real
Root Cause?
• Assign the task to a person (team if necessary)
knowledgeable of the systems and processes involved
• Define the problem
• Collect and analyze facts and data
• Develop theories and possible causes - there may be
multiple causes that are interrelated
• Systematically reduce the possible theories and possible
causes using the facts
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9. 9Determining Root Cause 9
How to Determine the Real
Root Cause? (continued)
• Develop possible solutions
• Define and implement an action plan (e.g., improve
communication, revise processes or procedures or work
instructions, perform additional training, etc.)
• Monitor and assess results of the action plan for
appropriateness and effectiveness
• Repeat analysis if problem persists- if it persists, did we
get to the root cause?
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10. 10Determining Root Cause 10
Useful Tools For Determining
Root Cause are:
• The “5 Whys”
• Pareto Analysis (Vital Few, Trivial Many)
• Brainstorming
• Flow Charts / Process Mapping
• Cause and Effect Diagram
• Tree Diagram
• Benchmarking (after Root Cause is found)
Some tools are more complex than others
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11. 11Determining Root Cause 11
Example of Five Whys for Root
Cause Analysis
Problem - Flat Tire
• Why? Nails on garage floor
• Why? Box of nails on shelf split open
• Why? Box got wet
• Why? Rain thru hole in garage roof
• Why? Roof shingles are missing
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12. 12Determining Root Cause 12
Pareto Analysis
Count 14 14 11 9 7 7 3 3 3 3162 2 2 1 513934 20 19 19 15 15
Percent 3 3 2 2 1 1 1 1 1 132 0 0 0 127 7 4 4 4 3 3
Cum % 86 89 91 93 94 96 96 97 97 9832 98 99 991005966 70 74 78 80 83
Count
Defect
O
ther
EB
Dam
aged
Supplier
Cleanliness
EB
Marking
Supplier Rusted, Corroded
EB
Incorrect
Material
EB
Docum
entation
EB
Dim
ension
Supplier Missing
Parts
ESD
Packaging
Supplier Lab
Test Failure
Supplier
Shelf Life
Exceeded
Supplier W
rong
Configuration
Supplier O
ther
W
orkm
anship
Supplier
Incorrect
Material
Supplier
Dam
aged
Packaging
Supplier Dim
ensions
EB
O
ther
Supplier Docum
entation
Supplier
Marking
180
160
140
120
100
80
60
40
20
0
Supplier Material Rejections May 06 to May 07
Vital Few
Trivial Many
60 % of
Material
Rejections
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13. 13Determining Root Cause 13
Cause and Effect Diagram
(Fishbone/Ishikawa Diagrams)
EFFECT
CAUSES (METHODS) EFFECT (RESULTS)
“Four M’s” Model
MAN/WOMAN METHODS
MATERIALS MACHINERY
OTHER
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14. 14Determining Root Cause 14
Cause and Effect Diagram
Loading My Computer
MAN/WOMAN METHODS
MATERIALS MACHINERY
OTHER
Cannot
Load
Softwar
e on PC
Inserted CD Wrong
Instructions are Wrong
Not Enough
Free Memory
Inadequate System
Graphics Card Incompatible
Hard Disk Crashed
Not Following
Instructions
Cannot Answer Prompt
Question
Brain Fade
CD Missing
Wrong Type CDBad CD
Power Interruption
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15. 15Determining Root Cause 15
Tree Diagram
Result Cause/Result Cause/Result Cause
Result Primary
Causes
Secondary
Causes
Tertiary
Causes
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16. 16Determining Root Cause 16
Tree Diagram
Poor Safety
Performance
Stale/Tired
Approaches
Inappropriate
Behaviors
Lack of
Employee
Attention
Lack of Models/
Benchmarks
No Outside Input
Research Not
Funded
No Money for Reference
Materials
No Funds for
Classes
No Consequences
Infrequent
Inspections
Inadequate
Training
No Publicity
Lack of Sr.
Management Attention
No Performance
Reviews
No Special Subject
Classes
Lack of Regular
Safety Meetings
Zero Written Safety
Messages
No Injury Cost
Tracking
Result Cause/Result Cause/Result Cause
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17. 17Determining Root Cause 17
Bench Marking
Benchmarking: What is it?
• "... benchmarking ...[is] ...'the process of identifying, understanding, and
adapting outstanding practices and processes from organizations
anywhere in the world to help your organization improve its
performance.'"
—American Productivity & Quality Center
• "... benchmarking ...[is]... an on-going outreach activity; the goal of the
outreach is identification of best operating practices that, when
implemented, produce superior performance."
—Bogan and English, Benchmarking for Best Practices
• Benchmark refers to a measure of best practice performance.
Benchmarking refers to the search for the best practices that yields the
benchmark performance, with emphasis on how you can apply the
process to achieve superior results.
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18. 18Determining Root Cause 18
Bench Marking
All process improvement efforts require a sound
methodology and implementation, and benchmarking
is no different. You need to:
• Identify benchmarking partners
• Select a benchmarking approach
• Gather information (research, surveys, benchmarking
visits)
• Distill the learning
• Select ideas to implement
• Pilot
• Implement
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19. 19Determining Root Cause 19
Common Errors of Root Cause
• Looking for a single cause- often 2 or 3
which contribute and may be interacting
• Ending analysis at a symptomatic cause
• Assigning as the cause of the problem the
“why” event that preceded the real cause
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20. 20Determining Root Cause 20
Successful application of the
analysis and determination of
the Root Cause should result
in elimination of the problem
and create Happy Campers!
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21. 21Determining Root Cause 21
Summary:
• Why determine Root Cause?
• What Is Root Cause Analysis?
• When Should Root Cause Analysis be
performed?
• How to determine Root Cause
• Useful Tools to Determine Root Cause
1. Five Whys
2. Pareto Analysis
3. Cause and Effect Diagram
4. Tree Diagram
5. Brainstorming
• Common Errors of Root Cause
• Where can I learn more?
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22. 22Determining Root Cause 22
Where Can I Learn More?
• “Solving a Problem & Getting Along: Toward the Effective Root Cause
Analysis”, Khaimovich,1998.
• “The Quality Freeway”, Goodman, 1990
• “Potential Failure Modes & Effects Analysis: A Business Perspective”, Hatty
& Owens, 1994
• “In Search of Root Cause”, Dew, 1991
• “Solving Chronic Quality Problems”, Meyer, 1990
• “The Tools of Quality, Part II: Cause and Effect Diagrams”, Sarazen, 1990
• “Root Cause Analysis: A Tool for Total Quality Management”, Wilson, Dell &
Anderson, 1993
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