5.4.4: Six Sigma
- Page ID
- 111208
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\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)You may end up accepting a job in an organization that has a Six Sigma Program. Six Sigma is a set of techniques and tools for process improvement. It was introduced by engineer Bill Smith while working at Motorola in 1980. It is a comprehensive quality system for achieving business success by minimizing variation in business processes. Six Sigma quality is used to describe a process so well controlled that there are no more than 3.4 defects per million opportunities
Six Sigma comes from the term in statistics of sigma, meaning standard deviation. It is a measure of the amount of variation in a set of data. A usual company process might operate at a 3 sigma quality level. This indicates that 99.73% of all output will fall between plus and minus three standard deviations of the mean. The result then would be that 0.27% of all results are non-conforming, or defective. This is equivalent to 2700 defects per million opportunities. This is not so good if the business is operating in an industry where quality is critical to customer safety, such as manufacturing of aircraft, cars or medical devices. A process with a Six Sigma capability generates 99.99966% defect free outputs.
Unique to Six Sigma is the DMAIC Improvement Model. In Six Sigma, improvements are made by the use of project teams. A team may be assembled in order to fix a quality issue, to streamline an old process or to develop a new process. The team will use the DMAIC model, which is an acronym that stands for Define, Measure, Analyze Improve and Control. Copyright © 1993 — American Society for Quality. All rights reserved. An explanation of the steps in the DMAIC process and some of the tools used are below.[6]
- Define the problem, improvement activity, opportunity for improvement, the project goals, and customer (internal and external) requirements.
- Measure process performance.
- Analyze the process to determine root causes of variation and poor performance (defects).
- Improve process performance by addressing and eliminating the root causes.
- Control the improved process and future process performance.
Figure \(\PageIndex{1}\): Cyclical diagram of the DMAIC model.
Also unique to Six Sigma is the use of the martial arts method of using coloured belts in order to symbolize the level of expertise in Six Sigma.
Green Belt is a designation indicating that an individual has had Six Sigma training. An individual with Green Belt status may have a full-time job in the organization but will be called upon to assist with projects part-time.
Black Belt is a full-time position in the Quality area where the individual works as a coach / leader in projects. These individuals will have extensive experience in Six Sigma.
Master Black Belt is a full-time position in the Six Sigma team with extensive experience in managing projects. They coach and mentor the Black Belt leaders.
Champion is usually a senior manager in the organization who oversees the other Six Sigma Quality employees. The work on determining which projects should be prioritized, ensuring proper allocation of resources and removing any roadblocks that may prevent success.
