Six Sigma is a business improvement methodology that was first used in the 1980s by companies like Motorola and Honeywell. By the 1990s, a long list of Fortune 500 companies had adopted Six Sigma in an effort to increase quality (and profits) by eliminating defects, service failures, and waste. Today, companies in almost every industry use Six Sigma to improve their operations, bottom-lines, and customer satisfaction.
All Six Sigma projects are managed using a set of tools and techniques across five phases known as the DMAIC framework: define, measure, analyze, improve, and control. Using statistical analysis, Six Sigma teams work to fix processes so they’re 99.997% defect-free, which translates to only 3.4 defects per million.
Six Sigma projects are managed by individuals with specific titles, roles, training, and certifications. These roles are identified by a hierarchical belt structure with darker belts representing roles that require more experience and training: white belt, yellow belt, green belt, black belt, and master black belt.
Six Sigma white belts are engaged at the first level of the Six Sigma process and have a basic understanding of Six Sigma concepts. They’re responsible for connecting with the next highest belt (green belts) to solve specific problems at a local level. Often, white belts are called upon to support an overall Six Sigma project but aren’t actually on the Six Sigma team.
Certification: Neither of the widely recognized Six Sigma certifying organizations, the International Association for Six Sigma Certification (IASSC) or the American Society for Quality (ASQ), offer a Six Sigma white belt certification. However, some universities and companies do offer this level of certification.
The yellow belt is the first level of Six Sigma certification. Yellow belts are Six Sigma team members who report to green belts. They understand the basics of Six Sigma, including the first three phases of the DMAIC framework: define, measure, and analyze. Yellow belts are responsible for reviewing process improvements in support of a Six Sigma project.
Certification: To obtain a Yellow Belt certification, you must pass a 60 question exam.
Six Sigma green belts are usually at the manager level and report to Six Sigma black belts. They’re considered to be the worker bees of a Six Sigma project because they do most of the data collection and analysis work. Green belts are knowledgeable on all phases of the DMAIC framework. Experienced green belts might lead small Six Sigma projects.
Certification: To obtain a Six Sigma green belt certification, you must have three years of work experience in one or more areas of the Six Sigma Green Belt Body of Knowledge (e.g., process improvement), and that experience must have been in a paying role. You are also required to pass the 1.5 hour, 100-question green belt certification exam.
Six Sigma black belts lead Six Sigma projects, green belts, and teams. They are Six Sigma experts with a great deal of experience. Black belts interface with executives and ensure Six Sigma project goals are met. They also act as coaches to people with lower level belts.
Certification: To obtain a Six Sigma black belt certification, you must have green belt experience and have completed two Six Sigma projects with signed affidavits. In addition, you have to pass the 4-hour exam, which includes 150 questions.
Master Black Belts
Six Sigma master black belts act as trainers and coaches to people with lower-level belts. Their role is typically strategic rather than project-based and focuses on Six Sigma at the program and enterprise level.
Certification: To obtain a Six Sigma master black belt certification, you need to have at least five years of experience as a Six Sigma black belt or a minimum of 10 completed Six Sigma black belt projects. In addition, you need to pass a two-part exam.
Other Six Sigma Roles
In addition to the Six Sigma belt designations, organizations typically have Six Sigma executives and champions. A Six Sigma executive’s role is to align the Six Sigma program with the company’s culture and strategy. The champion translates the company’s vision and goals into a comprehensive Six Sigma program and individual projects.
Each of these roles plays an important part in ensuring Six Sigma effectively improves a business and its profitability