This question delves into your background in Statistical Process Control (SPC), 6σ (Six Sigma), and if you know how to use Key Performance Indicator (KPI) metrics. There are other gauges to use, but these are commonly utilized.
Discuss the solutions you've done or can do. For instance, you can say something such as, 'I implemented visuals such as Lean Andon Lights on my last contract, which sped up response time to manufacturing floor issues. I also used 6σ run and control charts on my last job, generating them easily in apps such as Excel. I utilized these charts to identify and bring non-conformances back into acceptable ranges.'
Also, explain how you know how to do it if called upon for implementation. You could tell the interviewer, 'I learned how to use a control chart in my Statistical Process Control class. On the job, I used the chart to identify and bring the specifications for car paint in an auto manufacturing plant process under control.' To impress, present a printout of a chart you've generated at school or on the job.