Control Phase and Sustainment Flashcards
7 cards from real Lean Six Sigma Green Belt Certification practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Control Phase and Sustainment flashcards as text
After project closure, responsibility for sustaining process improvements typically transfers to:
Answer: The process owner or operations manager
The process owner or operations manager assumes accountability for sustaining improvements after the project team disbands, ensuring long-term ownership.
Which tool BEST helps identify which process inputs require monitoring in the Control phase?
Answer: FMEA with Risk Priority Numbers
The FMEA with Risk Priority Numbers (RPNs) prioritizes which failure modes and inputs pose the highest risk, directing control plan monitoring efforts to the most critical variables.
What is the difference between common cause variation and special cause variation?
Answer: Common cause is inherent to the system; special cause comes from assignable external factors
Common cause variation is the natural, inherent variation within a stable system, while special cause variation results from identifiable, assignable factors outside the system.
A Green Belt wants to verify the measurement system is still adequate before finalizing the control plan. Which study should be conducted?
Answer: Gage R&R study
A Gage R&R (Repeatability and Reproducibility) study evaluates whether the measurement system has acceptable precision relative to process variation and tolerances.
In a control plan, 'frequency' refers to:
Answer: How often a measurement is taken for a given CTQ or control variable
Frequency in a control plan specifies how often each characteristic must be measured (e.g., every hour, every 50 units) to detect shifts in the process in a timely manner.
Which of the following signals on an X-bar chart requires immediate investigation according to standard SPC rules?
Answer: One point beyond 3 sigma control limits
A single point beyond the 3-sigma control limits is the most fundamental out-of-control signal indicating a likely special cause that requires immediate investigation.
Mistake-proofing (poka-yoke) devices are preferred in the Control phase because they:
Answer: Prevent errors from occurring rather than detecting them after the fact
Poka-yoke devices are preferred because they prevent defects from being produced or passed forward, making them more effective than detection-based controls.