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What is Six Sigma? Description

Six Sigma is a quality management methodology that provides businesses with the tools to improve the capability of their business processes. This increase in performance and decrease in process variation lead to defect reduction and improvement in profits, employee morale and quality of product. It is a quality measure and improvement program that was pioneered by Mikel Harry and Motorola. It focuses on the control of a process until the point of six sigma (standard deviations) from a centerline, or 3. 4 defects per million items. It includes identifying factors which are critical for the quality as determined by the customer. It reduces process variation and improvement capabilities, increases stability and designs systems to support the six sigma goal.

The Six Sigma model is a highly disciplined approach that can help companies to focus on developing and delivering near-perfect products and services. It is based on the statistical work of Joseph Juran, a Rumanian-born US pioneer of quality management. The word “Sigma” is a Greek sign used for a statistical term that measures how far a given process deviates from perfection (standards deviation). If the sigma number is higher, you are closer to perfection. One sigma is not very good; six sigma is defined as only 3. 4 defects per million. The central idea behind Six Sigma is that if you can measure how many “defects” you have in a process, you can systematically figure out how you can eliminate them. Thus you can almost come to “zero defects”.

The Japanese origin of Six Sigma can still be seen by the system of “belts” which it uses. If you are new to Six Sigma and you go on a basic training, you get a green belt. Anyone who has the responsibility for leading a Six Sigma team is called a black belt. Finally there is a special elite group called Master Black Belts who supervise the Black Belts.

Five Steps in Six Sigma. Process

Typically, a Six Sigma process has the following five stages:

1. Definition. The first step in any Six Sigma project is to clarify the problem and narrow its scope in such a way that measurable goals can be achieved within a few months. Then a team is assembled to examine the process in detail, suggest improvements, and implement those recommendations. In the manufacturing world, project managers and their sponsors typically begin by defining what constitutes a defect and then establish a set of objectives designed to reduce the occurrence of such defects.
2. Measurement. In the second step of a Six Sigma project, the team gathers data and prepares it for high-level analysis.
3. Analysis. Once a process has been mapped and documented, and the quality of the hard supporting data has been verified, the Six Sigma team can begin the analysis. The team members usually start by identifying the ways in which people fail to act as needed, or by identifying the ways in which people fail to ensure effective control at each stage.
4. Improvement. Recommend, decide and implement improvements.
5. Control. In the final stage of a Six Sigma project, the team creates controls. These are enabling the company to sustain and extend the improvements.