Statistical Process Control (SPC) helps ensure that the solution created is maintained over time. By using these tools, your process can remain in control.

Statistical Process Control and Stability of Process

Predictable process vs unpredictable.

Predictable: variation coming from common cause variation – or variation inherent to the environment of the process.

Unpredictable: special cause variation exists.

Additional Statistical Process Control Resources

Run Chart

Control Chart

Control Limits

Specification Limits: Voice of the Customer. Shows what they will accept – or won’t/

Attribute Charts

EWMA Chart

X Bar R Chart

Great decision matrix here:

Statistical Process Control Videos

Six Sigma Green Belt Statistical Process Control Questions

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Questions, comments, issues, concerns? Please leave a note in the comments below!

Question: In the Control Phase of a LSS project a Belt will identify key metrics that can be monitored and analyzed to give an indication that a process may be moving towards an out of spec condition. When he applies this approach he is using __________________.

(A) Poisson Derivatives
(B) Inferential Statistics
(C) Kanban Analysis
(D) Statistical Process Control

Question: Statistical process control (SPC) is best defined as the use of

(A) Pareto charts to understand and control a process
(B) inputs to control critical and complex processes
(C) statistical methods to identify and remove manufacturing errors
(D) statistical methods to understand and control a process

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Comments (4)

Could you direct me to the AIAG information you mentioned in the control phase quiz? I followed the link provided but do not see the answer. I tried searching in the search bar but no results.

Larry, you don’t really need the Automotive Industry Action Group (AIAG) information. By definition out of control could be considered a certain number of points in a row on one side of the X Bar Bar or R in a control chart or a certain number of points in a row that are consistently increasing or decreasing.

I’ve seen some standards list 5 points and others list 7. The key to the question is knowing that a process shift or trend has begun if you see that behavior emerged.

I’ve updated the answer walkthrough with this.

You can find AIAG’s PDF on here:

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