Product & Process Control Tools

Juran defined the term Quality Control as the regulatory process through which we measure actual quality performance, compare it with quality goals, and act on the difference.

At this point in the production process, you should have already utilized a major control tool when you defined your critical quality parameters, and in relationship to Juran’s statement above, you were setting or planning your quality goals.

You should also have created a control plan to manage these critical items.

Now that you’ve moved from pre-production into full production, you now have the task measuring actual quality performance against quality goals you’ve set and acting on any deviations from that controlled process.

In this section you’ll learn 3 important topics and 1 important tool.

  • Product Control
  • Process Control
  • Service Control
  • Control Plan & Work Instructions (Tool)

Product, Process & Service Control

Product Control is all about using your Control Plan to closely monitor and measure those critical quality features to ensure conformance to the product design. A tools within the Product Control section is the Requirement Matrix.

According to ASQ, the Requirements Matrix is a tool to help ensure that the control requirements are translated into actions that can be measured and managed.

Process Control can encompass both your product process and your service process.  In Delivering Quality Service, 5 Critical Dimensions of Quality Service are outlined below.

  • Reliability – Your ability to perform the promised service dependably and accurately.
  • Responsiveness – This is a measure of the promptness of your service.
  • Assurance – A measure of your courtesy, and the resulting trust built with the customer.
  • Empathy – Your ability to be caring and show special attention to your customer.
  • Tangibles – A measure of the physical Aesthetics of your team.

Similarly to Product Process Control, Service Process Control must also be carefully considered as it greatly impacts things like repeat sales and customer service. In the same way that we performed a pre-production planning phase for Product Process Control, Service Process Control must also be challenged to ensure that all critical parameters have been identified and addressed on your Control Plan.

Control Plan & Work Instructions

A Control Plan is a document that details what is required to maintain a process at its current level. This can include information about training, tooling, equipment, specifications, limits, procedures or testing for each task. Once you’ve created a Control Plan, you should create an additional Reaction Plan.

The Reaction Plan will let your team know what action needs to be taken if they deviate from the Control Plan. The Reaction Plan has 4 generic sections below.

  • Containment – If non-conformances are suspected, they need to be quarantined and segregated from normal product.
  • Disposition – Your team must now investigate the non-conformance and its impact to the customer to determine the disposition (Scrap, rework, Use-As-Is, RTV)
  • Diagnosis – Now that you’ve dispositioned the product it’s now time to go back determine the root cause and perform Corrective Action.
  • Verification – As part of the Corrective Action process, you need to ensure that the changes you made to the process is effectively mitigating the root cause you determined.

Another tool that is often used in process control is the Work Instruction.

Work Instructions are simply a document to help someone perform a job correctly. Work Instructions should be clear, easily understood, and accessible to those performing the work. As a compliment to Work Instructions, Visuals Aids or Job Aids can also be used to enhance your written communication and provide clarity to the instructions.

These additions can provide great clarity to your work instructions, preventing mistakes and reducing the learning curve for new employees.