Lean Six Sigma Yellow Belt Certification Control and Sustainment Methods 3 — Questions and Answers
Question 1: Why are Standard Operating Procedures (SOPs) critical to sustaining process improvements?
- They allow management to reduce headcount
- They capture the best-known method and ensure consistency across operators and shifts (Correct answer)
- They replace control charts in the Control phase
- They eliminate the need for quality audits
Correct answer: They capture the best-known method and ensure consistency across operators and shifts
SOPs document the improved process steps so all operators perform the work consistently, preventing regression to old habits.
Question 2: Which element is most important to include in a Standard Operating Procedure for sustainment?
- Project charter reference
- Step-by-step instructions with expected outcomes and quality checkpoints (Correct answer)
- SIPOC diagram
- Affinity diagram results
Correct answer: Step-by-step instructions with expected outcomes and quality checkpoints
Effective SOPs include clear step-by-step instructions and quality checkpoints so operators know both what to do and what a good outcome looks like.
Question 3: A 5S audit is conducted during the Control phase primarily to:
- Identify new improvement projects
- Verify that workplace organization standards are being maintained (Correct answer)
- Calculate the cost of poor quality
- Redesign the process layout
Correct answer: Verify that workplace organization standards are being maintained
5S audits in the Control phase confirm that Sort, Set in Order, Shine, Standardize, and Sustain practices are being upheld over time.
Question 4: What is the main risk of failing to update SOPs after a process improvement?
- Increased material costs
- Operators revert to old methods, eroding the gains (Correct answer)
- Project documentation is incomplete
- The control chart will be invalidated
Correct answer: Operators revert to old methods, eroding the gains
Without updated SOPs, operators may default to pre-improvement habits, causing the process to regress and wasting the improvement effort.
Question 5: Which training approach best ensures operators can sustain a new process standard?
- Sending an email announcement about the change
- Hands-on training with return demonstration and competency verification (Correct answer)
- Posting the SOP on the bulletin board
- Providing a one-time classroom lecture
Correct answer: Hands-on training with return demonstration and competency verification
Return demonstration lets the trainer verify the operator can correctly perform the new method before working independently.
Question 6: Which document links each process step to its key control variables, measurement method, and responsible owner?
- FMEA
- Control Plan (Correct answer)
- SIPOC
- Project Charter
Correct answer: Control Plan
A Control Plan maps each critical process step to what is measured, how it is measured, frequency, and who is accountable.
Question 7: During a process audit in the Control phase, an auditor finds operators are skipping a step defined in the SOP. The BEST immediate action is to:
- Revise the control chart limits
- Retrain operators and investigate why the step is being skipped (Correct answer)
- Remove the step from the SOP
- Escalate to senior leadership only
Correct answer: Retrain operators and investigate why the step is being skipped
Retraining corrects the behavior while investigating the root cause determines whether the SOP step needs adjustment or reinforcement.
Lean Six Sigma Yellow Belt Certification Control and Sustainment Methods 3
Why are Standard Operating Procedures (SOPs) critical to sustaining process improvements?