Process Stability And Capability (PSC)

This module is a supplement to the ACIP which focuses on continuous process improvement. Process stability focuses on improving stability and capability of processes to ensure customer satisfaction. It:

• Crystallizes the differences between special and common causes
  Shows how to put Statistical Process Control into practice and stabilize a process
• Shows how to estimate and improve the capability of a process

One of the guiding principles of the Anaar philosophy is:

“Salaries are paid by satisfied customers”.

Customers expect consistency in the quality of products and services they receive. Variation in quality is undesirable and is the enemy of quality.

Variation is inherent in every process; we cannot completely eliminate it. If you look closely enough, you will always find some variation. Therefore, our objective should be to reduce the magnitude of variation.

Variation comes from two types of causes:

• Common causes
• Special causes

Special causes are assignable, specific in nature, whereas common causes are systemic in nature. Special causes require a different treatment than common causes.

Taking action, in response to a special cause, as if it were a common cause results in making unnecessary adjustments to the processes (tampering with the process). Consequences, most often, will be discouraging to disastrous.

Taking action, in response to a common cause, as if it were a special cause ignores the fundamental causes inherent in the process and leads to finger-pointing with no improvement in the output.

Hence, as Dr. Deming put it, it is of utmost importance that we understand the very nature of the cause of variation – whether it is a special cause or a common cause – before taking action.