Six Sigma seeks to improve the quality output of processes by identifying and removing the causes of defects (errors) and minimizing variability in manufacturing and business processes. It uses a set of quality management methods, mainly empirical, statistical methods, and creates a special infrastructure of people within the organization ("Champions", "Black Belts", "Green Belts", "Yellow Belts", etc.) who are experts in these methods. Each Six Sigma project carried out within an organization follows a defined sequence of steps and has quantified value targets, like increase productivity, increase efficiency, reduce pollution, reduce cost, increase customer satisfaction, increase profits and become more competitive. Sigma is the designation for the standard deviation, and a process capability of six standard deviations equals 3,4 defect per million opportunities. That is an ambitious goal! It requires continuous improvement and focus on understanding variation to gain control of production.

Six Sigma projects follow a project methodology inspired by Deming's Plan-Do-Check-Act Cycle. It includes 5 phases and bear the acronym DMAIC. DMAIC is used for projects aimed at improving an existing business process.

  • Define the system, the voice of the customer and their requirements, and the project goals, specifically.
  • Measure key aspects of the current process and collect relevant data; calculate the 'as-is' Process Capability.
  • Analyse the data to investigate and verify cause-and-effect relationships. Determine what the relationships are, and attempt to ensure that all factors have been considered. Seek out root cause of the defect under investigation.
  • Improve or optimize the current process based upon data analysis using techniques such as design of experiments (DOE), Components of variation (CoV), poka yoke or mistake proofing, and standard work to create a new, future state process. Set up pilot runs to establish process capability.
  • Control the future state process to ensure that any deviations from the target are corrected before they result in defects. Implement control systems such as statistical process control - SPC, production boards, visual workplaces, and continuously monitor the process.

To me Six Sigma means;

  • Reducing process variation
  • Continuously improving
  • Facts rather than assumptions
  • Being open minded, seeking more than one solution
  • Strong focus on cost reduction
  • Prevention rather than fire fighting
  • Systematic way of working
  • Specific targets and performance monitoring
  • Practical application of statistics
  • Being curious and ask questions

DMAIC model

Six Sigma continuously improve processes by following the DMAIC model:

My Six Sigma experience

I started working at Cytec in 2002, where I was introduced to Six Sigma. My training in U.S. with skilled and committed colleagues and instructors made me thrilled about the tools and mindset. Through my studies, I had experience in statistics, but Six Sigma introduced me to new areas and I found it more practical. Working with continuous improvement, my Six Sigma training provided me valuable knowledge and has improved the quality of my work. Six Sigma black belt certification In 2004 I received my Black Belt certification Six Sigma in Six Sigma. Since then I have worked in chemical manufacturing, pharmaceutical industry and food processing in addition to environmental technology. My experience is that manufacturing companies face many of the same challenges and tools within Lean and Six Sigma can create great value for manufacturing.