## Six Sigma – Details Unveiled

Do you have a Six Sigma Certification? Employers often seek professionals with Six Sigma certification as they are expected to be proficient in using strategies and tools aimed at process improvement.

Sigma is a Greek letter ‘σ’ assigned to represent the amount of variation or inconsistency exhibited by a measurable outcome. Six Sigma uses the DMAIC (Define, Measure, Analyze, Improve, Control) approach to find out what is causing defects within a given process and to determine what changes are necessary to make the system efficient and error free.

### Why is it called Six Sigma?

In statistics, the symbol Sigma (σ) depicts Standard Deviation, which measures the amount of variation within a set of data. In a normal data set, a variation of one standard deviation above the mean includes 84.1% of the total population below that value. If we extrapolate this to six standard deviations above the average, then we get a calculated value of 99.9999998% or 2 parts per billion. This means that a process functioning at this level will yield only two defects for every billion items produced, or a process or system functioning with a high level of perfection.

### Highlights and Benefits of a Six Sigma System

What started as a brain child of Motorola way back in 1985, gained popularity when in 1995 Jack Welch of General Electric made it the pivotal of his business strategy. Today a Six Sigma system is an enterprise-wide strategy that recognizes the problematic areas of the business and defines improvement efforts for projects. It determines and implements data-driven, breakthrough-level solutions in a predictable and repeatable manner that improves business results. It enhances output process and quality through the identification and removal of the causes of errors and the minimization of variability in the business and manufacturing processes.

### How is Six Sigma Deployed?

Six Sigma strategy employs various techniques of quality management such as statistical methods. When a Six sigma project is undertaken in an organization, it follows defined series of steps and value targets that are quantified such as increasing customer satisfaction and profit while reducing pollution, process time, and cost. At the basic level it is a process improvement tool set. When linked to corporate strategy it becomes an operating philosophy of great assistance to the accomplishment of corporate objectives.

Six Sigma follows DMAIC as the problem-solving methodology. Here is the overview of the objectives and in each of the phases of DMAIC (Define, Measure, Analyze, Improve, Control).

• Define: Define the customer, the critical quality issues of the company, identify the problems, zero in on the core business processes and those that need improvement.
• Measure: Determine the current processes involved, identify the key improvement measures, and develop a data collection plan for the process.
• Analyze: Do data analysis by applying statistical tools to determine the root causes of defects and the opportunities for improvement.
• Improve: Improve performance and process, identify the sources of variation, design solutions to fix and prevent problems, and validate the realized results.
• Control: Implement improvement methods such as documentation and deployment of an ongoing monitoring plan to ensure that the enhanced performance is maintained.

## Top Six Sigma Tools for Better Results

Six Sigma uses specific tools to solve business problems. Six Sigma tools are used to improve processes to do things better, faster, and at lower costs. They are also used to modify and/or design new processes, improve current processes, decrease downtime, and improve customer response time. They can be applied to every facet of business, from production, to human resources, to order entry, to technical support. To think like a Black Belt professional and to understand Six Sigma methodologies, tools, techniques, and approaches required to drive improvements in business processes the Six Sigma Primer course is immensely helpful.

Within the individual phases of a DMAIC project, Six Sigma utilizes many established quality-management tools. Several such tools are used, but all the tools are not used on all projects. Trained Black Belt professionals understand the process improvement tools available in each phase, and know where and how to apply them.

1. In the Define phase it is important to define at least one Critical To Quality (CTQ) measure. The Pareto chart is often used to categorize complaints or reported problems by category. The SIPOC (Suppliers, Inputs, Process, Outputs, Customers) process map is also a valuable tool at this stage.

2. Some of the important tools used in the Measure phase include trend charts, basic Pareto charts, process and control charts, Gage R&R, Process Sigma, Stratification, Time Series Plots (Run Charts), Prioritization Matrix. During the measuring phase, tools are used to determine whether improvement can be achieved by the implementation of quality enhancing changes.

3. In the Analyze phase, the most commonly used tools are:

a. Pareto Chart

b. 5-Why

c. Hypothesis Testing

d. Regression Analysis

e. Cause and Effect/Fishbone Diagram

f. Time Series Plots

g. Histograms

h. Scatter Diagrams

i. PFMEA (Process Failure Mode Effects Analysis)

4. Following Six Sigma tools are commonly used in the Improve phase where process redesign is the main focus:

a. Regression Analysis

b. Hypothesis Testing

c. Design of Experiments (DOE)

d. Analysis of Variance (ANOVA)

5. The Control phase includes tools such as control charts, process maps, and monitoring plans.

At the end of the Control phase, the project team should have successfully standardized and documented the new process, created training and reference materials and established a plan for a sustained process monitoring. After implementing all the phases, the improvements are fully established and a plan exists for updating the process for any situational or environmental changes. The team is now ready to close the Six Sigma project and transfer the ownership of the process to the owner. At the closure stage, the team can make future recommendations or suggest steps to handle problems that were discovered during the present implementation but were not addressed.

## Six Sigma Certifications

Six sigma strategy is employed by organizations to facilitate efficient, effective, cheaper and faster service to their clients. It is important a company develops a unique group of human resource who are experts in these methods. These Six Sigma professionals are necessary for a company’s survival as their expertise help a company to overcome different shortcomings and improve quality to near perfection. It may be a great idea to jump into the bandwagon of Six Sigma professionals who are in great demand in businesses. So waste no time as getting certifications and preparing for them through the courses Six Sigma Green Belt and Six Sigma Black Belt certifications will add a great boost to your career.

Page Last Updated: April 2014