For more than a century, the industrial world has seen great efficiency and growth in production of higher quality. This quest was charted by individuals like Walter Shewhart (The Grandfather of Total Quality Management), Kaoru Ishikawa, Frederick Taylor, Shigeo Shingo, and many others. Their quest is still operational today as theories and methods for improvements are posited, reviewed, tested, and implemented.
One of the most significant and stand-out methodologies — Six Sigma, has found itself to be a very effective module. Being in the market for the past 35-40ish years, Lean Six Sigma has proven to be a foolproof methodology to reduce errors and increase productivity.
Introduced and refined in the manufacturing department of Motorola in 1986 by an American engineer Bill Smith, Six Sigma seeks to improve manufacturing quality by identifying and removing the causes of defects and minimizing variability in manufacturing and business processes.
A quick look into Six Sigma
A Six Sigma processes 99.99966% of all opportunities to produce some feature of a part that are statistically expected to be free from defects.
It’s a continuous improvement process, with a focus on:
- Changing empowerment
- Seamless training of resources
- Consistent top management support
To get a detailed insight on Six Sigma head towards our blog
The Six Sigma Process
The term Six Sigma is derived from the statistical process modeling in manufacturing. A “SIGMA” is a measurement of standard deviation (often abbreviated as “s” or “σ”). Anything that is between +/- 6s from the centerline of a control chart is considered to be well controlled. In other words, there is very little deviation from the standard and is within the tolerance zone.
The 68-95-99.7 Rule mentioned above in the diagram is known as an Empirical rule. It is used to remember the percentage of values that lie within a bandwidth around a normal distribution with a width of 1σ, 2σ, and 3σ respectively. A perfectly carried out Six Sigma process produces 99.99966% of opportunities free of defects. The process produces 3.4 defects per million opportunities (DPMO).
There are multiple Sigma levels where each of them indicates the number of allowed defects per million and thus the level of process maturity. The table goes as follow:
|Sigma Level||Defects per Million||Defects %|
Primary Elements of Six Sigma
1) Customers – Customers are the market king. They are the key for any business and are always on (should be!) top priority. They define the quality requirements. They also mold the delivery, performance, service statistics.
2) Process – Defining processes and corresponding metrics is the key aspect of Six Sigma. Since the customer defines a business’s growth, quality needs to be in check from their perspective. This will help to identify the gaps in the processes and the work needed to be improved.
3) Employee – Without decent leadership, Six Sigma implementation is very difficult. The organization must involve its employees with well-defined roles, responsibilities, and objectives.
Six Sigma Methodologies
Now that you know the basic working of Six Sigma, let’s dive into the two primary methodologies:
1) DMAIC – Used for existing processes. Maximizes & stabilizes business processes and designs
DMAIC stands for –
- D – Define – Identifies problems/objectives that need attention
- M – Measure – Provides a measure of the problem or process
- A – Analyze: Identifies the root causes of any deficiencies and opportunities
- I – Improve – Finds solutions to address problems
- C – Control – Implements and maintains improvements for sustainability
2) DMADV – Used for new processes, products, or services.
DMADV stands for –
- D – Define – Identifies problems or goals that need attention
- M – Measure – Provides a measure of customer’s needs
- A – Analyze – Identifies the process that meets customer’s expectations
- D – Design – Develops a process to meet customers’ needs
- V – Verify – Confirms the ability to meet customer’s requirements
3) DFSS – Used for developing or redesigning a net new product or service. The process follows these steps:
DFSS Stands for-
- Define – Determines customer needs.
- Identify – Identifies customer and project specifics.
- Design – Develops processes to meet customer’s expectations.
- Optimize – Identifies abilities to deliver and maximize design elements.
- Verify – Testing and validation of any deliverables.
Six Sigma Belts
Six Sigma is a process that requires thorough knowledge and understanding of various processes and methodologies. And for such, it requires hands-on training and experience to carry out the process to fruition. So individuals start with basic levels and grow in the process gradually. The entire Six Sigma process is divided into a belt system that determines the level of knowledge and experience an individual has. The belts are divided as follow:
- Six Sigma White Belt – They provide problem-solving support to teams and are not directly involved in Six Sigma projects (work mostly on sidelines).
- Six Sigma Yellow Belt – They are project members who assist with Six Sigma process improvement and provide project support.
- Six Sigma Green Belt – Individuals with this belt help in collecting information/data and provide necessary analysis. They are also responsible to lead projects that are of Green Belt level.
- Six Sigma Black Belt – They are project leaders that solve high-level problems and provide coaching to team members.
- Six Sigma Master Black Belt – An even higher level where individuals tend to be more at the program level and provide coaching for Black Belts and Green Belts. They are responsible for determining strategy and developing KPIs.
As the global factors on how to run a business are changing, so are the rules and regulations. Achieving operational excellence is what businesses strive to achieve these days. And, it has been proven that businesses that adopt Six Sigma into their process tend to achieve more over time. It might seem slow at first but the change is that comes with it is fruitful.