root cause analysis
TRANSCRIPT
Successful Corrective Action Through Effective
Problem Solving
IT470a Six Sigma Green Belt-ISummer 2009
Reference Material #2
Ken White
K White 2/12/2009 2
Course Objectives
• Understand the basic structure of the C/PA Process
• Understand how to define a problem to allow a solution
• Review of basic root cause analysis tools
• Understand the importance of tracking and completing C/PA Steps
K White 2/12/2009 3
#1 - Describe the Problem
#2 - Determine the Root Cause
#3 – Determine C/PA Steps
#4 - Verification
#5 - Conclusion
Date Issued: KNAM Quality CPA Number: (Sector ID/Originator Initials/No. assigned)
Corrective Action Preventive Action
Section A: Incident Summary
1. Title:
2. Failure of KNAM Requirements:
QPE (List reference)
QCMS (list section)
OTHER (describe)
3. Description of the nonconformity:
Date of incident:
Describe the issue:
Who identified the issue?
Where was the issue identified?
What are the consequences?
Location:
Other circumstances that potentially contributed to the issue
4. Root Cause (5 “WHYS”):
Section B: Plant identified CPA or Corporate driven Activities Describe the actions to be taken, assigned responsibilities and target completion dates 1. Action Steps: “PLAN – DO”
What Who Target Completion Date Date completed
“CHECK – ACT” 2. Verification: Details must include description of evidence reviewed such as type of data, observation, titles and data range of records reviewed 3. Conclusion:
Effective Not Effective If not effective, explain: Verification Completed By:
Date:
K White 2/12/2009 4
Problem Description
If we do not define the problem correctly, we will never be able to solve the problem --- PERMANENTLY
K White 2/12/2009 5
Symptoms• Any circumstance, event or condition
that accompanies something and indicates its evidence or occurrence; a sign
Examples of symptoms:– Procedures are not followed– Operator error– Incomplete information
• Ensure you break through symptoms by asking “WHYS”
K White 2/12/2009 6
Problem Description• Must be clearly defined• Define in terms of WHAT, WHERE,
WHEN, WHO, HOW MUCH, and the CONSEQUENCES
Example:
At 9:07 p.m., mixer operator found 2”x 4” metal piece in mix tank #5. The cook process was stopped immediately – batch #1-8 were put on hold.
K White 2/12/2009 7
1. What was affected? Be specific about product type, lot numbers,
location, customers 2. Where did the problem take place?
Be specific about where the problem was found, department, equipment, customer
3. When was the problem discovered? Be specific to times, shifts, end of production
run, monthly period clean 4. Who discovered the problem?
Internal or external persons, position, customer
1. How much was affected? Think in terms of pounds, units, dollars, number
of customers 2. How often has this problem occurred?
Is this the first time or has the same or similar issue happened in the past
1. What is the consequence of this situation? Late or short shipments, delayed start-up,
downtime, product loss, loss of customer
The 4W/ 2H/ 1C FORMULA
K White 2/12/2009 8
Problem DescriptionCommon mistakes• Defining the problem and the solution at
the same time– The lot tags were not found on the pallet
and the supervisor has shown the operator the correct location for placement.
• Defining a symptom as the problem– The operator was confused on how to place
the label on the pallet.
• Defining the problem without data to support definition. – The case operator works slowly.
K White 2/12/2009 9
Problem Description
Avoid mistakes• State WHAT is wrong, not WHY it’s
wrong• Define the “gap” between what is
expected and what is actually happening
• As new information/data becomes available review and update the problem description as necessary.
K White 2/12/2009 10
Step #2Determining the Root Cause
What is a root cause?The single, verifiable reason for the problem, which if corrected – prevents its recurrence.
K White 2/12/2009 11
Problem Solving Tools Brainstorming The act of defining a problem
or idea and coming up with anything related to the topic – no matter how remote a suggestion may sound.
K White 2/12/2009 12
BrainstormingHow to Facilitate• Assign a scribe – set a time limit• Ask each member to contribute an idea or
suggestion• Allow no positive or negative comments about
the suggestions, at this point• Record all possible causes or sources of a
problem• Evaluate the responses as a group discussion
– Look for answers that are repeated or similar– Group like-concepts together– Eliminate responses that definitely do not fit
• Decide which cause to attack first, by voting
K White 2/12/2009 13
Problem Solving Tools5 Whys• Helps to identify the relationship
between causes• Forces you to “drill down” the
symptoms
Problem Cause
Cause
Cause
Why? Why?
Why?
Why?
Why?
Cause
ROOToot
K White 2/12/2009 14
5-WhysHow to facilitate
• Write down the specific problem• Ask “Why the problem happens” and write the answer
down below the problem• If the answer you just provided doesn't identify the root
cause of the problem that you wrote down in step 1, ask Why again and write that answer down
• Loop back to previous step until the team is in agreement that the problem's root cause is identified.– May take fewer or more times than five Whys.
• Please note that the 5 WHYs make take the group down multiple paths – and that’s OK.
K White 2/12/2009 15
Problem Solving Tools
• 5 Why’s• Check Sheet• Pareto Chart• Time Line• Fishbone
K White 2/12/2009 16
Problem Solving Tools
Check Sheets
• For Collecting data and is Useful when data is needed to determine frequency, patterns, defects by type or location
K White 2/12/2009 17
Check SheetOperators Name(s) Sandy Bauer, Eddie Banks, Steve Larsen
For week of: January 21 - 25, 2003
How Many times did it happen Total
IIII IIII IIII IIII II 22IIII IIII IIII I 16IIII IIII III 13IIII IIII IIII IIII IIII II 27IIII IIII II 12IIII IIII II 12IIII IIII I 11IIII II 7Wrong label
No sealContainer missingCodes missingCan't read printer
Packaging Issue
Wrap was looseNo labelsBubbles
K White 2/12/2009 18
Pareto Chart
27
22
16
13 12 1211
7
0
5
10
15
20
25
30
No Seal Loose Wrap No Labels Bubbled No container Missing CodeDates
Unreadableprint
Wrong Label
Packaging Defects
Count
Working on top ½ of your causes may help 2/3 of the problems go away!
65%
K White 2/12/2009 19
Problem Solving Tools
Develop a Time Line• Provides a clear picture for
understanding the incident and how it evolved
• Record known changes– Must be specific with verifiable
facts
K White 2/12/2009 20
Time Line ExamplePackage Defects (rejects) have suddenly increased
Jan. 1st March 1st
Average Line Speed 500 packages per minute Average Line Speed 600 packages per minute
Feb. 1st
Reject Rate 3% Reject Rate 10%
1/2Running 1 shift with
experienced employees
1/4Hired 30 new employees
1/5Trained new employees
1/10 Started 2nd
shift operation
1/2016 hour
equipment PM
completed
2/3 Implemented
new packaging material
2/5 Increased line speed
2/1010 more new employees
more training
View Check Sheet
K White 2/12/2009 21
Problem Solving ToolsCause and Effect Diagram• Also referred to as “fishbone”
diagram• Useful for organizing large
amounts of information about a problem
• Most effective when done as a team with individuals who are knowledgeable of the overall process
K White 2/12/2009 22
C & E Diagram• As a group, identify what the major
categories of causes are to the process. – Most common:
- People - Materials - Equipment - Environment - Methods - Measurement
K White 2/12/2009 23
C & E Diagram
Problem Product placed on hold due to
uneven distribution of fruit topping. This caused uncontrollable weights and below standard appearance of finished product
K White 2/12/2009 24
C & E Diagram
UNEVEN FRUIT APPLICATION ON
PRODUCT
ENVIRONMENT
METHODSPEOPLE
MATERIALS
EQUIPMENT
Temporary Position
Excessive downtime
Scale errors
Room Temperature
Temperature
Tote size
Excessive waste
Poor Inspections
Overloading hopper
Tote size
K White 2/12/2009 25
Prioritizing Activities
EASY DIFFICULT
HIGH
LOW
DIFFICULTY
IMPACT
1 32
2 41
K White 2/12/2009 26
Step #3C/PA Steps
Well defined steps…
Can be the difference between a successful resolution or one that falls short of preventing recurrence
K White 2/12/2009 27
C/PA Steps
The process:• Formalize and capture the activities
that need to take place• Clearly identify:
– WHO is going to do WHAT by WHEN
• Use an Action Register to track activities
K White 2/12/2009 28
C/PA Steps• Monitor the status of the activities
– Continually update action register (adding new tasks, completion dates)
– Add as a standard agenda item in department meetings, management review
• Maintain action register as part of the C/PA Program
K White 2/12/2009 29
Step #4Verification
Verification needs to be supported by evidence :
– Type of data• What was reviewed (charts, observation, records)
– Observations
– Titles and data range– Records reviewed– Who was interviewed– Summary of overall findings
K White 2/12/2009 30
Step #5Conclusion
• Confirms the solution - has fixed the problem so it doesn’t come back
• Confirms that the system change is effective
• Process• People
• May need additional long-term monitoring– Incorporate as an internal audit check point
Questions
K White 2/12/2009 32
Additional ResourcesReferences• Correct! Prevent! Improve! – ASQ (American
Society of Quality) publication • The Root Cause Handbook – Max
Ammerman• The Basics of FMEA (Failure Mode and Effect
Analysis) – McDermott, Mikulak, Beauregard. Focus is on machinery and safety
Courses• Problem Solving and Decision Making
Problem Solving and Decision-Making: A Course in Critical Thinking Skills