A one-page Lean Six Sigma Green Belt reference: exam facts plus the DMAIC tools you must know. Use it for final review. Confirm all current details on the IASSC certification page.
Exam facts
| Item | Detail |
|---|---|
| Questions | 100 (closed book; some forms +10 unscored) |
| Time | 3 hours |
| Pass mark | 70% minimum |
| Cost | ~US$350 voucher (confirm with IASSC) |
| Prerequisites | None |
| Body | IASSC (vendor-neutral; others like ASQ differ) |
DMAIC and key tools by phase
- Define - project charter, voice of the customer (VoC), CTQ tree, SIPOC diagram.
- Measure - process map, data types, measurement-system analysis (MSA), process capability (Cp, Cpk).
- Analyze - root-cause tools (fishbone, 5 Whys, Pareto), hypothesis testing, correlation, regression.
- Improve - solution selection, piloting, FMEA, mistake-proofing (poka-yoke).
- Control - control plan, statistical process control (SPC) charts, standard work.
Core concepts
- Variation - Six Sigma reduces process variation and defects using data.
- Defect / DPMO - a defect fails a CTQ; DPMO measures defects per million opportunities.
- CTQ (Critical to Quality) - the measurable requirements that matter to the customer.
- Green Belt role - supports or leads smaller projects, often part-time under a Black Belt.
Common traps
- Underestimating the statistics in Measure and Analyze.
- Learning tools in isolation instead of by DMAIC phase.
- Skipping Control, where improvements are sustained.
- Confusing the IASSC route with ASQ’s - they are different bodies.