Statistical Quality Control (SQC) / Statistical Process Control (SPC)

Statistical Process Control

Statistical Process Control (SPC) : A method used for measuring, analysing, detecting and controlling process variation. This method may include the measurable quality characteristics control chart along with other techniques.

  –X-Bar and R Chart
  –X-bar and S Chart
  –np and p Chart
  –c and u Chart
Statistical Quality Control (SQC) : The application of statistical techniques (SPC and statistical sampling) to control product characteristics to ensure it meets product specifications or the engineering design specification.

Why SPC / SQC?

  • It is more economic to assess a sample of product and use the result to predict the properties of the whole lot.
  • It leads to predictions with a high degree of precision.
  • 100% inspection is not actually 100%.


  • Provide Knowledge about the basic SQC_SPC techniques and its application to our working environment.


To understand :
  • The variability
  • Data types
  • Basic statistical tools and their applications
  • How to reduce variability in product and processes through statistical tools.
  • How to measure and monitor process performance