Quality control charts usually have a central line and upper and lower control limit lines.Which of the following is not a reason that the process being monitored with the chart should be investigated?
A)A large number of plots are close to the upper or lower control lines.
B)The behavior of the plots is erratic.
C)A single plot falls above or below the control limits.
D)Thee is a change in raw materials or operators.
E)There is a run of five above the central line.

Question

Quizplus · Accepted Answer

A change in raw materials or operators is not directly related to the data plotted on the control chart and does not indicate a process issue by itself. The other options indicate potential issues with the process being monitored.

Quality Control Charts Usually Have a Central Line and Upper