Six Sigma believes that if one can measure how many defects are in a process, one can figure out how to systematically eliminate them and get as close to perfection as possible. For a company to achieve Six Sigma, it cannot produce more than 3.4 defects per million operations or products.
There are two Six Sigma processes: Six Sigma DMAIC and Six Sigma DMADV. The terms are derived from the major steps in the process. Six Sigma DMAIC involves a procedure that defines, measures, analyzes, improves, and controls existing processes that fall below the Six Sigma specification. Six Sigma DMADV, on the other hand, defines, measures, analyzes, designs, and verifies new processes or products that are trying to achieve Six Sigma quality.
Let’s say you are running a pizza delivery business and you set a target of delivering pizzas within 25 minutes of receiving the order. If you achieve that 68% of the time, you are running at 1 Sigma. If you achieve it 99.9997% of the time then you are at 6 Sigma. It means you are late on average only 3.4 times out of every one million orders.
Motorola created two terms to assess Six Sigma processes: Six Sigma Green Belt and Six Sigma Black Belt. People who are certified either Green Belt or Black Belt can execute all Six Sigma processes. Using DMAIC as the basis for improvement, a Six Sigma Green Belt can basically demonstrate the use of techniques to measure and analyze processes, and demonstrate the use of techniques to improve and control processes. Practical experiments demonstrate how the selection of these tools impact on the success of a Six Sigma project.
A certified Six Sigma Black Belt is able to explain Six Sigma philosophies and principles, including supporting systems and tools. The Black Belt can demonstrate team leadership, understand team dynamics, and assign team member roles and responsibilities. They have a thorough understanding of and can use all aspects of the DMAIC model by following the Six Sigma principles. They have basic knowledge of lean enterprise concepts, are able to identify non-value-added elements and activities, and are able to use specific tools.
