DMAIC Phase 5: The Control Phase of Six Sigma and Its Tools Including Process Monitoring Plan, Control Charts, and Process

DMAIC Phase 5: The Control Phase of Six Sigma and Its Tools Including Process Monitoring Plan, Control Charts, and Process
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Objectives of Control Phase

<img src="https://img.bhs4.com/c3/8/c38b1554b6f97f261064f074486a1e5fe8a41017_large.jpg" alt="The 5th Phase in the Six Sigma DMAIC Process: Control">

The primary objective of the DMAIC Control phase is to ensure that the gains obtained during Improve are maintained long after the project has ended. To that end, it is necessary to standardize and document procedures, make sure all employees are trained and communicate the project’s results. In addition, the project team needs to create a plan for ongoing monitoring of the process and for reacting to any problems that arise.

Standardizing and Documenting the Improvements

The first step of the Control phase is to document and standardize the improvements that were rolled out during Improve. This takes several forms.

The process map of the new process that was created during Improve should be reviewed and updated as necessary to reflect any modifications that may have occurred during roll out. It will be used for training and reference so that the new process will be clear. If many individuals or groups are involved in the process, a deployment flowchart should also be developed to clarify roles and tasks.

While a process map is a key component of the documentation of the new process, it is usually also beneficial to have a user guide which spells out the steps of the process and provides rationale. This is particularly important if multiple improvements were made and if the new process is substantially different from the original.

Finally, the project team will ensure that everyone involved in the process receives proper training and that effective communication occurs. Training may involve actual classroom learning or may consist simply of distributing the process documentation. This is a great opportunity to confirm that the process map and user guides are effective.

Creating a Process Monitoring Plan

Perhaps the most critical aspect of Control is establishing a plan to monitor the new process and act when results are not up to spec, so that the project gains will be maintained. It is this component of Six Sigma projects that tends to distinguish them from basic project management methodology, whereby the project is closed out once the improvement is confirmed. The monitoring plan clarifies how the process performance will be continuously monitored, who will be notified if there is a problem and how that will happen and what response is required.

The first part of the monitoring plan specifies the metrics that will be tracked to summarize process performance, as well as specifying how and how often they will be tracked. Also be sure to clarify who is responsible for doing it; usually it falls to the process owner. Typically the metrics used during Measure and Improve and established as Critical To Quality (CTQ) measures during Define are appropriate.

The monitoring plan also indicates what constitutes satisfactory performance and what should be considered a red flag indicating possible problems. The team should brainstorm potential issues and appropriate responses for each. Again be sure to specify not only what needs to be done but who is responsible for making it happen.

A control chart should be continuously updated so that the process owner can watch for process shifts or other signs that there may be a problem with process performance. If the process owner is not well versed in interpreting control charts, the project team should create a reference sheet indicating what the process owner should be looking for. If possible, use an automated process to flag the process owner when performance becomes questionable.

Finally, since further change in the process environment is inevitable, the project team should develop a process for updating the new procedures when required. The update process will include updating the process map and user guides, communicating the changes to all involved, and modifying the monitoring plan if necessary to reflect the changes. Common changes that the team should plan for include shifts in employee roles, changes in customer specs and replacements for existing technology.

Wrapping Up the Control Phase

By the end of the Control phase, the project team has successfully standardized and documented the new process, created training and reference materials and established a plan for ongoing process monitoring. The improvements are fully established and a plan exists for updating the process in response to changes in the environment. The team is now ready to close out their Six Sigma DMAIC project and hand the process off to the process owner.

Closing Out the Project

The five phases of DMAIC have been completed. The Six Sigma project team has:

  • Established the customer requirement (CTQ)
  • Measured the process against that requirement
  • Clarified the problem that had to be addressed
  • Confirmed one or more root causes of that problem
  • Identified one or more solutions to counter the root causes
  • Demonstrated that the solutions implemented result in substantial improvement in the CTQ metrics
  • Rolled out the new process
  • Standardized and documented the new process
  • Created a plan for monitoring the process and responding to performance problems

It is now time to close out the project. This should include formally transferring ownership of the process from the project team back to the process owner. It is also a great opportunity for the team to make recommendations for next steps. Perhaps additional DMAIC projects are in order to cover problems that were not addressed with this project. In some cases the team may have uncovered some potential quick fixes or enhancements that leadership could implement without a Six Sigma project.

Finally, the team should celebrate the end of a successful Six Sigma DMAIC project. These projects are neither quick nor easy and it is worth acknowledging both the effort that went into successful completion and the benefits that resulted. The celebration could be a formal one or a simple gesture; each team can decide for itself which is appropriate.

This post is part of the series: The Six Sigma DMAIC Process

This series provides an introduction to the Six Sigma DMAIC process, and a more in-depth look at each of the individual phases. You’ll learn about the objectives of each phase and common tools to help you reach them.

  1. DMAIC Phase 1: Define
  2. DMAIC Phase 2: Measure
  3. DMAIC Phase 3: Analyze
  4. DMAIC Phase 4: Improve
  5. DMAIC Phase 5: Control