Question

When using the SPC methodology, a system is said to be stable when:

• A. the system is efficient
• B. the mean and range of variation caused by the system are controllable
• C. the mean and range of variation caused by the system are predictable
• D. the performance of the system is improving

Hint:

A stable system in SPC means the variation is predictable, which helps in maintaining consistent quality. If variation is unpredictable, it may be a sign of underlying issues that need to be addressed.

Answer 1

The Correct Option is C

In SPC, a system is considered stable when the variation in its performance is predictable. This means that the mean and range of variation caused by the system are under control and do not exhibit any abnormal fluctuations. Stability in SPC refers to the system being in a state of statistical control, where the variation is due to common causes and not special causes. Predictability allows for effective monitoring and decision-making, ensuring that the system consistently operates within acceptable limits.