Sigma Six

Six Sigma (Sigma Six) is a measure of quality that strives for near perfection. The Sigma Six process uses data and rigorous statistical analysis to identify "defects" in a process or product, reduce variability, and achieve as close to zero defects as possible.

Using a universal measurement scale, Sigma Six defines and estimates the opportunities for error and calculates defects in the same way every time, thus offering a means for measuring improvement. In fact, Sigma Six takes its name from the Greek letter "sigma," which is used in statistics to indicate standard deviation.

Sigma Six at many organizations simply means a measure of quality that strives for near perfection. Sigma Six is a disciplined, data-driven approach and methodology for eliminating defects (driving towards six standard deviations between the mean and the nearest specification limit) in any process—from manufacturing to transactional and from product to service.

A quality measure and improvement program developed by Motorola that focuses on the control of a process to the point of ± Sigma Six (standard deviations) from a centerline, or 3.4 defects per million items. It includes identifying factors critical to quality as determined by the customer, reducing process variation and improving capabilities, increasing stability and designing systems to support the six sigma goal.

The statistical representation of Sigma Six describes quantitatively how a process is performing. To achieve Sigma Six, a process must not produce more than 3.4 defects per million opportunities. A Sigma Six defect is defined as anything outside of customer specifications. A Sigma Six opportunity is then the total quantity of chances for a defect. Process sigma can easily be calculated using a Sigma Six calculator.

Sigma Six methodology is a proven tool set for driving and achieving transformational change within an organization. It is a business improvement process that focuses an organization on customer requirements, process alignment, analytical rigor, and timely execution.

The Sigma Six methodology incorporates this data and statistical analysis into a project-based workflow that allows businesses to make intelligent decisions about where and how to incorporate improvements.

Ultimately, Sigma Six is about more than numbers. It's a highly disciplined methodology and practice that provides the tools you need to achieve consistent, high-performance results from your products and processes. By increasing performance and decreasing variation, Sigma Six allows organizations like yours to make customer-focused, data-driven decisions that ultimately yield a reduction in product defects, increased profits and employee morale, and high-quality products - a win-win situation for everyone involved.