Six Sigma is a methodology for quality improvement based on reducing defects and process variation.
Six Sigma was initially implemented by Motorola and has become a popular management and process improvement strategy. The successful adoption of Six Sigma methodology by Jack Welch at General Electric has instilled a strong sense of Six Sigma philosophy across many industries. In statistical terms, Six Sigma refers to the the study of process capability, a Six Sigma process has less than 3.4 DPMO (defects per million orders) and there are six standard deviations between the mean and the nearest specification limit (upper or lower specification limit).
Six Sigma Methodology
Six Sigma has a strong emphasis on statistical analyses, metrics and the DMAIC approach to problem solving: define, measure, analyze, improve, and control. DMAIC is central to any process improvement intitative.
The ASQ definitions of DMAIC
- 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, poor performance (defects).
- Improve process performance by addressing and eliminating the root causes.
- Control the improved process and future process performance.
Six Sigma and lean philosophy are contiguous, both strive towards quality and process improvement with similar strategies. Six Sigma utilises empirical measures and statistical analyses to detect and eliminate defects and process variation. Lean is primarily focused on waste minimisation and value. Both systems operate in synergy for maximum efficiency, productivity and quality improvement.
Implementing a Lean Six Sigma Project in your company and laboratory
Six Sigma Organisation
|Six Sigma Hierarchy|
An effective Six Sigma (SS) project is reliant on knowledge of Six Sigma philosophy and statistics, successful use of the tools and metrics, team engagement and commitment from all stake holders. In a Six Sigma organisation there is a hierarchy of members that are involved in Six Sigma initiatives, ranging from the Champions or Sponsors to Black belt leaders and team members. Six Sigma project requires support from management and company executives i.e. Champions or enables that provide resources for SS implementation. A Master Black Belt (MBB) is a highly skilled and experienced Black Belt who is an expert in the use of Six Sigma tools and statistics. The MBB is a mentor to other black belts and is responsible for the management and implementation of numerous Six Sigma programs. Black Belts lead Six Sigma projects and are highly skilled in Six Sigma methodologies with extensive knowledge of the use of statistics, SS tools and project management. Green belts are trained in Six Sigma methodologies and statistics; Green Belts generally assist Black Belts on large projects or lead smaller projects. Team members also include Yellow Belts, White Belts and process owners who assist in project realisation and effective implementation of Six Sigma.
Team Lean Sigma
Defining the problem and goals are the first steps in the DMAIC cycle to continuous improvement! After defining the project a Lean Six Sigma team must be established. Leadership and team commitment is critical to the success of a project. Toyota House of Quality emphasises employee empowerment and respect for people, two attributes which contribute Lean Six Sigma (LSS) success. When establishing a team for a LSS project in your laboratory it is important that members range from having a diverse skills background to subject matter experts. Members should adopt a culture of LSS culture and be involved in assisting with data collection and feel "empowered" to implement changes for process improvement. Regular meetings must be scheduled to ensure consistent deployment of LSS tools, data collection metrics analysis, review progress and present results. The use of tools and statistics at all stages of the DMAIC process is the main strategy towards Lean Six Sigma deployment .