Six Sigma Terminology

Understanding Six Sigma terminology is becoming more and more important nowadays as organizations are waking up to the benefits of this methodology. . And why shouldn’t they? After all, Six Sigma offers a good theoretical mechanism for improving quality and reducing the number of defects. In this modern age of consumerism where merely satisfying the customer’s requirements is not enough, adopting Six Sigma practices to improve your process ensures a sure-fire way of retaining your customers.

One problem though with Six Sigma is that like many project management methodologies it has it’s own terms and terminology. This can make you feel alienated when your colleagues throw the Six Sigma jargon at you. However don’t despair. Just keep reading as this article makes an effort to define the Six Sigma terminology in simple and easy-to-understand terms.

Certain key terms of the Six Sigma terminology that you should be aware of are listed below:

1.0 Six Sigma

When you define Six Sigma you realize it is a methodology adopted for improving processes by reducing variation and standardizing the process to achieve a near zero defect product. It is the specific measure of quality that strives to deliver a product that has less than 3.4 defects per million opportunities.

2.0 Defect

A defect is defined as any non-conformance to the expected quality characteristics of a product or a process as expected by the customer. The occurrence of a defect causes frustration to the customers and results in monetary loss to the party producing the defect.

3.0 Critical to Quality (CTQ)

A characteristic of the final product which is one of the parameters for adjudging the quality of a product is defined as critical to quality. It is a key measurable trait of the final product and is critical for satisfying the customer’s expectations.

4.0 DMAIC

These are the steps in Six Sigma methodology which comprise five stages –Define (D) Measure (M), Analyze (A), Improve (I), and Control (C). The key activities for each of these stages are:

4.1 Define (D)

The nature of the problem, project business case and problem statement are defined, and the successful project team and project charter are formulated during this stage.

4.2 Measure (M)

The actual performance is measured and data is gathered during this stage.

4.3 Analyze (A)

The data gathered during the measure phase is analyzed and the gap between the desired and actual performance is identified during this stage.

4.4 Improve (I)

Process improvements are devised, a pilot project is undertaken, and implementation plans are designed during the Improve stage.

4.5 Control (C)

Process improvement is undertaken and measures are devised to sustain the improved process during the Control stage.

5.0 Defects per Million Opportunities (DPMO)

Before defining defects per million opportunities, let’s first understand the meaning of the term ‘number of defect opportunities’. The number of defect opportunities stands for the total number of defects that can occur in a product. For calculating this, you need to know all the parameters that are Critical to Quality (CTQs) for the customer. The number of defect opportunities therefore is the sum total of defects that can happen in a product.

6.0 Control Chart

The control chart is a graphical tool that helps monitor the variance over time in any process. Any unexpected variance might result in a defect.

7.0 Tollgates

Tollgates mark the conclusion of each stage of the DMAIC process while adopting the Six Sigma methodology. A tollgate review is conducted after each stage to ascertain the outcome of each stage and to ensure that the objectives defined for each stage have been achieved.

8.0 Black Belt

A Black Belt is a certified Six Sigma quality position in an organization. Black Belts are responsible for mentoring Six Sigma improvement processes and provide valuable guidance to the team running Six Sigma projects.

Six Sigma Terminology - Tip

While executing a Six Sigma improvement process, it is imperative that the project team is trained on Six Sigma tools and are familiar with all the Six Sigma terminology.

---