Six Sigma Overview

In this Six Sigma Overview, we'll explain what all the hype is about, and why this methodology has taken hold worldwide. The methodology is considered to be primarily a business management strategy that is focused upon improving business processes by the minimization and/or elimination of variation and defects (we like using the term errors instead of defects).

This focus begins with understanding that everything that occurs in a company can be considered a process, and as such, can be monitored, measured, and controlled in some fashion. The in-depth study of processes is what contributes to the reduction in variation and to increased profitibility. Simply stated, as variation and errors are reduced, profits increase.

What's Not New?

  • Stable and predictable processes are the initial goal of Six Sigma and should also be considered mission-critical to your company, as well as enhancing customer satisfaction.. A stable process is one that does not exhibit excessive variation.
  • Business processes must be measured, analyzed, improved, and controlled
  • Sustained improvement can only be achieved with top management commitment

What Is New?

  • Strong emphasis on quantifiable results, including financial gains from Six Sigma projects
  • Clearly defined roles within an organization, Facilitators, Black Belts, Green Belts, Yellow Belts
  • Data driven decision making using analytical tools
  • Operational Excellence

Six Sigma Historical Overview

The methodology has its roots in the statistical concepts of process capability. 6σ (the Greek letter Sigma) can be compared to the process capability indices Cpk or Ppk. This table shows the relationship between capability values and sigma values

Sigma ValueCpkDPMOYield
6 2 3.4 99.99966%
5 1.67 230 99.977%
4 1.33 6210 99.379
3 1 66,800 93.29%
2 0.67 308,000 69.2%
1 0.33 690,000 31%

As you can see by the above chart, once you calculate the process capability, it is simple to determine your process sigma value... you just multiply the Cpk value by 3!

Your organization's profitability increases significantly with each movement toward a higher sigma level, particularly if you have under performing processes.

Six Sigma Overview 
The Methodology

The methods utilized in this six sigma overview are loosely based upon Deming's PDSA Cycle (Plan-Do-Study-Act). The 5 phases of the 6σ DMAIC process are defined as follows:

  • Define Here the problem solving team defines the problem in specific terms and creates the project charter
  • Measure Collection of existing process data, and/or the creation of new data collection methods
  • Analyze Examination of the data to determine the problem causes
  • Improve Determination of the steps to take to eliminate or minimize the problem at hand
  • Control Verification steps to ensure the gains achieved by the project can be sustained

Six Sigma Overview 
The Belts

Different levels of expertise have been classified by the 6σ practitioners. From Master Black Belt, Black Belt, Green Belt, all the way to Yellow Belt, the specific level of knowledge has its own set of requirements for Six Sigma certification. With the exception of the Yellow Belt, certification tests are given to ensure the individual can successfully utilize the body of knowledge required for their skill level.

Why 6σ is Important

Ever since Motorola initiated the first six sigma movement, thousands of companies have saved millions of dollars using the methods prescribed. And although many know that there are no new tools being used, the accountability inherent to 6σ is what makes it important! The systematic approach to process improvement, plus the focus on the business case for each project make for an outstanding improvement program.

Honestly, the majority of the good 6σ training available comes at a hefty price... but the payback your company receives from just one black belt project pays for itself in under one year! How's that for a return on investment!

Cost of Poor Quality Creating a Problem Statement

6 σ Master Black Belt
6 σ Black Belt
6 σ Green Belt
6 σ Yellow Belt
Six Sigma Training


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