PFMEA Control Plans

Process FMEA Scope

Control Plans assure a system is in place to control the risks of the same failure modes as identified in the PFMEA. While Control Plans can be developed independently of PFMEAs, it is time and cost-effective to link Control Plans directly to PFMEAs. There should never be a difference between the PFMEA and the Control Plan.

In fact, we recommend that companies use software that automatically generates the Control Plans and Work Instructions from the PFMEA data.

A further extension of the PFMEA and Control Plan is that work instructions should be identical to the Control Plan.

The primary intent of Control Plans is to create a structured approach for control of process and product characteristics while focusing the organization on characteristics important to the customer.

 A Control Plan does assure well thought-out reaction plans are in place in case an out-of-control condition occurs and provides a central vehicle for documentation and communication of control methods.

 Special attention is typically given to potential failures with high RPNs and those characteristics that are critical to the customer.

Control Plans deal with the same operations covered in a FMEA plus some additional ones. The primary additions to the Control Plan are:

 Identification of the control factors.
 The specifications and tolerances.
 The measurement system.
 Sample size.
 Sample frequency.
 The control method.
 The reaction plan.

FMEAs and Control Plans are dynamic, not static, documents.

 Just like work instructions, make FMEAs and Control Plans a living document.
 As changes in product or process characteristics, specifications, measurements systems, sampling, control methods, or the reaction plan are identified, update the FMEA and the Control Plan.
 Use the revision as a communication tool to spread the word of the changes to the supply chain.
 By making the FMEA and Control Plan living documents, you can be sure that potentials for failure are continually being eliminated or reduced.