A final step of the Lean Six Sigma process improvement roadmap Define-Measure-Analyze-Improve-Control (DMAIC) is control. One aspect of control is to create a control plan.
A well-made control plan in an organization helps avoid the negative business impact from process deterioration. A control plan can include steps that are needed to be timely undertaken when performance measures are not within a desired range. An organizational system needs to be in place so that process owners take ownership of the execution of a control plan for their area of the business.
To enhance service quality, a control plan should be constructed by a designated team and the process owner. Over time, the plan should be updated depending on the evaluations after its implementation.
Seven attributes to consider when creating a control plan are:
1.1 Measurements and Specifications
A control plan is one aspect that is related to the maintenance of quality in a product or service. Relative to this assessment, one needs to consider that quality is a type of measure that can be viewed from the perspective of the customer. For instance, this view point is the way a next-step or final-use customer could view the service, product or operations quality as a function of how well certain specifications are met.
The team assigned with control planning could use gap models to study the differences between the customer measures and the actual specifications. For this consideration, one should address:
• Defining quality features
• Finding how to measure the features
• Setting up quality standards and forming control against the produced standards
By doing so, operations can insure that the production or delivery of products and/or services to a certain specification. A predictive 30,000-foot-level performance reporting methodology has many benefits for this type of reporting, especially when the metrics are aligned to an organizations value chain and these metrics are automatically updated.
1.2 Input/Output to a Process
Input and output or I/O in control planning is viewed as an incorporated process that usually involves the following:
• Planning a favourable input/output range of performance in a certain time period.
• Measuring and reporting feedbacks of the key inputs that can impact the process’ output.
• Timely correcting conditions that are out of control.
This area allows the planning team to identify the necessary actions to achieve the desired output.
1.3 Processes Involved
A control plan is to address the needs of vital processes. A most important aspect of control is setting the standards which represent the performance criteria. The main challenge in this area is to define a preferable and precise set of quantitative standards that are to be used for performance tracking.
Process execution should be poke-yoke or error-proofed steps in a process whenever possible. Process automation should be considered whenever this makes economic and physical sense. Lean and Six Sigma techniques can be used to improve processes relative to performance.
1.4 Frequency of Reporting and Sampling Methodology
The frequency of performance reporting depends on the products or services that are involved. This frequency should be established so that appropriate timely actions can be taken. Periodically management reviews may address how organizational processes, in general, are performing with their controls.
A major consideration lies with sampling. Thus, control planners must be able to select the right fraction of the population, products or services for inspection. The size of the sample and sampling techniques should be mastered as well to make use of the right technique when conducting statistical sampling. This leads to a more accurate assessment.
1.5 Recording of Information
All information in a control plan should be well documented for better assessment, planning, testing, and implementation. A central repository is needed for storing control plan information that can be accessed by those who have a need for the information.
Individual plan sheets for different products and processes may be created. By taking note of vital information such as quality, customer service, production, shipping and other areas, the corresponding problems in the products or processes can be identified and corrected. The recorded information serves as the formal request for things to be modified and shall be classified according to complexity, impact and importance.
1.6 Corrective Actions
Corrective actions serve as the response to problems that are detected. The actions that may be taken include: fixing the problem itself or modifying systems to avoid reoccurrence. Issues may arise in this area when the documentation failed to show that the problems were identified, corrected and controlled to ensure that the issue will not reoccur.
To illustrate this point consider: a massive batch pre-assembled product generated a month ago was identified be performing outside specification limits when subjected for final assembly. This is a problem that has been detected. Corrective actions should be made to prevent delays in production and most of all, negative financial impact in the part of the manufacturing company. In addition, corrective actions should reduce the likelihood of reoccurrence of the problem.
1.7 The Process Owner
Who is/are responsible for the ownership? Process owners are the concerned groups and individuals who possess the authority to impact execution and changes to the process’ operations. They are the ones responsible in meeting the needs of the customers.
Essentially, the process owners face many challenges. First, they should know about the critical areas of the processes involved. Second, they should be able to keep an eye on the process performance with backup data. Third, they are also responsible for ensuring that the process is updated, intact and well documented. Overall, the process owners are those who should conduct regular process reviews to guarantee and sustain satisfactory current and future performance.
Organizations benefit when the above seven attributes are addressed during the creation of a control plan.