Lean Six Sigma · level 2 of 3
Lean Six Sigma Green Belt certification
The Green Belt leads improvement projects within their own scope: framing, measuring, analysing with statistical tools, improving, sustaining. Syllabus, expectations and preparation.
Who this level is for
For an engineer, technician, quality manager, team leader or manager who will lead improvement projects part-time, alongside their job.
What is assumed to be mastered: The Yellow Belt syllabus is assumed to be mastered. Being comfortable with numbers is necessary — not a university level of statistics, but the ability to read a standard deviation, a scatter chart and a test result.
What the level covers
The Green Belt is the first level that commits to results. It takes a project from the observed problem to the sustained solution, following the DMAIC approach: define, measure, analyse, improve, control.
The Lean part covers flow and workstation tools: value stream mapping, SMED, kanban, takt time, levelling, productive maintenance, standardised work, error-proofing devices.
The Six Sigma part is what really sets this level apart from the previous one: process capability, measurement system validation, control charts, hypothesis tests, regression, failure mode analysis, first designs of experiments. This is where most exam failures happen — not because of mathematical difficulty, but because these tools require knowing which one applies to which question.
On top of that comes running the project itself: framing it with a charter, listening to the customer, keeping a data-collection plan, proving the gain, and handing control of what has been improved over to the process.
How to prepare
Two mistakes come up again and again. The first is revising the tools one by one without ever putting them back in DMAIC order: in the exam, one question in three is less about the tool than about when it is used. The second is avoiding calculation questions, which look thankless — they are in fact the most rewarding, because a capability index or a risk priority number is always calculated the same way.
Useful practice therefore alternates the two: situational questions that make you place the tool in the approach, and calculations repeated until they cost nothing.
Who awards the certification
As for the other levels, several organisations award Green Belt certifications according to their own bodies of knowledge. Some require a real, documented project on top of the written exam; others do not. That difference is the most structuring one for your preparation, and it is checked with the organisation you are aiming for.
beltup awards no certification and is not affiliated with any certification body. It is a practice tool for the body of knowledge, independent of the exam you will take.
What beltup covers for this level
1,073 questions carry the Green Belt level, across 27 topics deep enough to fill a whole session. A track at this level also draws from the lower levels — the fundamentals stay on the syllabus — for 2,070 questions in total, most of them at the target level.
Every question carries an explanation and the source it comes from.
- TPM
- SMED
- Heijunka
- DOE
- Capabilité
- ECRS
- DFSS
- MSA
- VSM
- Régression
- SPC
- Tests d'hypothèse
- Poka-Yoke / Jidoka
- IPP
- AMDEC
- DMAIC
- Kanban
- Résolution de problèmes
- Statistiques descriptives
- Flux
- SIPOC / VOC
- Yamazumi
- Maison du Lean
- Takt Time
- Standardisation
- Gaspillages
- Kaizen
Frequently asked questions
Do you need to be a Yellow Belt before the Green Belt?
Rarely mandatory, but always useful. Most organisations do not require the lower level as a formal prerequisite; the Green Belt syllabus, however, assumes the Yellow vocabulary and tools are mastered, and exam questions do not re-explain them.
What level of mathematics is needed for the Green Belt?
That of a science-track secondary diploma or a first technical cycle is enough. You need to be comfortable with means, standard deviations, percentages and reading charts, and understand what a risk of being wrong means. The calculations asked for are mechanical once the formula is known; the difficulty is choosing the right tool, not carrying out the calculation.
Is a real project required to be certified Green Belt?
It depends on the organisation. Some bodies of knowledge require a documented project with measured gains, others limit themselves to a knowledge exam. Check this point first: it changes the length of the preparation far more than the syllabus itself.
How long does it take to prepare for a Green Belt?
Several months of regular revision for the knowledge part, more if a real project is required. The volume is clearly greater than for the Yellow Belt, especially on the statistical side, and it does not stick well when crammed: short repeated sessions beat a few long ones before the deadline.
What is the difference between a Lean Green Belt and a Six Sigma Green Belt?
Some organisations separate the two traditions: a Lean-oriented Green Belt emphasises flow, lead time and shop-floor tools; a Six Sigma-oriented Green Belt emphasises variability, measurement and statistics. Most current bodies of knowledge bring them together under the name Lean Six Sigma, and cover both.
Practise at this level
Fifteen Green Belt-level questions, marked and explained, with no account and no bank card. To go further, the Green Belt Lean Manager track draws from the whole question bank of the level.
The notions to review first
- DMAIC— DMAIC est la démarche de résolution de problèmes en cinq phases — Définir, Mesurer, Analyser, Innover, Contrôler — qui structure tout projet Six Sigma.
- Cartographie de la chaîne de valeur (VSM)— La VSM représente sur une seule feuille le flux physique et le flux d’information d’un produit, de la commande à la livraison, pour rendre visible le temps où rien ne se passe.
- SMED (changement rapide d’outil)— Le SMED réduit le temps de changement de série en séparant ce qui peut être préparé machine en marche de ce qui exige l’arrêt, puis en convertissant le second en premier.
- Capabilité (Cp, Cpk, Pp, Ppk)— Les indices de capabilité comparent la dispersion d’un processus à l’intervalle de tolérance : Cp mesure ce dont le processus serait capable s’il était centré, Cpk ce dont il est capable tel qu’il est.
- AMDEC— L’AMDEC recense méthodiquement les modes de défaillance possibles d’un produit ou d’un processus, évalue leur gravité, leur fréquence et leur détectabilité, et hiérarchise les actions à mener avant que la défaillance ne survienne.
- Kanban— Le kanban est un signal — carte, bac ou emplacement vide — qui autorise à produire ou à réapprovisionner, et qui met le flux en tiré plutôt qu’en poussé.
The other levels
Lean Six Sigma Yellow Belt certification
For someone who takes part in improvement projects without leading them: operator, technician, clerk, first-line supervisor, or anyone whose company is starting a Lean initiative.
Lean Six Sigma Black Belt certification
For an experienced professional who will lead cross-functional projects full-time or most of the time, coach Green Belts and report to senior management.
beltup is an independent practice tool. It awards no certification and is not affiliated with, accredited by or endorsed by any certification body. Trademarks and non-affiliation