Certified Lean Six Sigma (CLSS) Exam*

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ATMAE's Lean Six Sigma Certification will equip learners with the knowledge, skills, techniques, and strategies to improve work environment and sustain organization market position. The Certified Lean Six Sigma (CLSS) program is meant for individuals who are currently working on or seeking work on Lean Six Sigma projects. Exam candidates should have a good background in quality, statistics, and lean philosophies. Lean Six Sigma Certification enables professionals to gain extra income (at least $20,000 more than a non-certified candidates). The career opportunities for Lean Six Sigma certified professionals can be broad, for example, health care, construction, service industry, manufacturing, operations, office, higher education, supply chain, and many other fields. The ATMAE Lean Six Sigma exam covers 12 main content areas and is further divided into 88 subcategories. The exam is divided into two main parts: the first part consists of 100 multiple choice questions that are worth 1 point each. The second part of the exam is composed of 25 multiple choice questions that require an examinee to solve a production or statistical problem that may take several minutes. Because of the time constraints, these questions are worth 4 points each. Therefore, each of the parts is worth 100 points and the combined scores from these two parts are used to calculate the examinee’s final score on the exam. A report of how well the examinee performed on each of the 12 main areas and 88 subcategories is available after the exam is completed. This report is a useful for reviewing any areas of weakness in case the examinee would like to retake the exam to earn a higher belt distinction. Textbooks from which the content for this exam was developed from are listed after the sample questions section of this Study Guide

Belt Distinctions for the ATMAE Lean Six Sigma Exam

Depending upon the grade earned by the examinee taking this exam, an individual can earn one of three different belt distinctions:

Lean Six Sigma Yellow Belt: examinees that earn a score of 40-59% on the exam (cutoff passing scores are evaluated annually and raised or lowered accordingly).

Lean Six Sigma Green Belt: examinees that earn a score of 60-79% on the exam.

Lean Six Sigma Black Belt: examinees that earn a score of 80% or higher on the exam. 

Lean Six Sigma Master Black Belt: Individuals that earned a score of 80% or higher on the exam and would like to be classified as Lean Six Sigma Master Black Belt must meet the following guidelines:

  1. Submit a lean six sigma project to the ATMAE Certification Board that they have completed as well as one from an individual that they are assisting with on a project. Submit to admin@atmae.org 
  2. All projects must be pre-approved by the ATMAE Certification Board before being initiated. Candidates will have up to three years to complete the projects once final approval is provided by the ATMAE Certification Board.
  3. An additional fee is charged for reviewing the projects. In addition, all projects must have the approval by the candidate’s supervisors and a financial statement must be included with the submission of the project.


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Certified Lean Sigma (CLSS) Exam
125 Questions  |  1 attempt  |  120 minute limit  |  80/200 points to pass  |  Graded as Pass/Fail
125 Questions  |  1 attempt  |  120 minute limit  |  80/200 points to pass  |  Graded as Pass/Fail You may edit any of your answers PRIOR to submitting the exam. Please remember to make a note of the questions/answers you would like to review. Answers cannot be changed after the exam is submitted. All questions must be answered and the exam submitted before the 120 minute mark. If the exam is not submitted the session will time out, and you will fail the exam.